MT
77 tal-2006 - Regolamenti tal-2006 li jemendaw ir-Regolamenti dwar Miżuri kontra l-Emissjoni ta’ Tniġġiż pej minn Gass u Partiċelli Żgħar minn Magni ta’ Kombustjoni Interna (Makkinarju Mobbli mhux Stradali)
Table of Provisions (12)
Statutory Text (12 Articles)
L.N. 77 of 2006
ENVIRONMENT PROTECTION ACT
(CAP. 435)
Measures against the Emission of Gaseous and Particulate
Pollutants from Internal Combustion Engines (Non-road Mobile
Machinery) (Amendment) Regulations, 2006
BY VIRTUE of the powers conferred by article 9 of the
Environment Protection Act, the Minister for Rural Affairs and the
Environment has made the following regulations>-
(1) The title of these regulations is Measures against the
Emission of Gaseous and Particulate Pollutants from Internal
Combustion Engines (Non-road Mobile Machinery) (Amendment)
Regulations, 2006 and shall be read and construed as one with the
Measures Against the Emissions of Gaseous and Particulate Pollutants
from Internal Combustion Engines (Non-road Mobile Machinery)
Regulations, 2001, hereinafter referred to as “the principal regulations”.
(2) These regulations implement the provisions of Directive
2004#26#EC of the European Parliament and of the Council of 21 April
2004 amending Directive 97#68#EC on the approximation of the laws
of the Member States relating to measures against the emission of
gaseous and particulate pollutants from internal combustion engines to
be installed in non-road mobile machinery.
In regulation 2 of the principal regulations>
(a) immediately after the definition “engine type” there shall
be added the following new definition>
“ “Flexibility scheme” means the procedure allowing
an engine manufacturer to place on the market, during the
period between two successive stages of limit values, a limited
number of engines, to be installed in non-road mobile
machinery”<”
(b) immediately after the definition “information package”
there shall be added the following new definition>
“ “inland waterway vessel” means a vessel intended for
use on inland waterways having a length of 20 metres or more
and having a volume of 100 m 3 or more according to the
formula defined in Annex I, Section 2, point 2.8a, or tugs or
pusher craft having been built to tow or to push or to move
alongside vessels of 20 metres or more>
Provided that this definition does not include>
a. vessels intended for passenger transport carrying no
more than 12 people in addition to the crew,
b. recreational craft with a length of less than 24 metres
(as defined in Article 1(2) of Directive 94#25#EC of the
European Parliament and of the Council of 16 June 1994 on
the approximation of the laws, regulations and administrative
provisions of the Member States relating to recreational craft*)
c.
service craft belonging to supervisory authorities,
d.
fire-service vessels,
e.
naval vessels,
f. fishing vessels on the fishing vessels register of the
Community,
g. sea-going vessels, including sea-going tugs and
pusher craft operating or based on tidal waters or temporarily
on inland waterways, provided that they carry a valid
navigation or safety certificate as defined in Annex I, Section
2, point 2.8b”<”
(c) immediately after the definition “non-road mobile
machinery” there shall be added the following new definition>
“Original equipment manufacturer (OEM)” means a
manufacturer of a type of non-road mobile machine<”.
In regulation 4 of the principal regulations, immediately after Amends regulation
4 of the principal
sub-regulation (3) thereof there shall be added the following new sub- regulations.
regulation>
“(4) Compression ignition engines for use other than in
propulsion of locomotives, railcars and inland waterway vessels
may be placed on the market under a flexible scheme in accordance
with the procedure referred to in Annex XIII in addition to
paragraphs 1 to 5”.
In regulation 6 of the principal regulations, immediately after
sub-regulation (5) thereof, there shall be added>
“(6) Compression ignition engines placed on the market
under a flexible scheme shall be labelled in accordance with Annex
XIII.”.
The following new regulation 6A shall be added immediately
after regulation 6 of the principal regulations>
“6A. (1) The following provisions shall apply to
engines to be installed in inland waterway vessels>
Provided that paragraph (2) and (3) shall not apply until
the equivalence between the requirements established by these
regulations and those established in the framework of the
Mannheim Convention for the Navigation of the Rhine is
recognised by the Central Commission of Navigation on Rhine
(hereinafter> CCNR) and the Commission is informed thereof.
(2) Until the 30 th June 2007, the competent authority
may not refuse the placing on the market of engines which
meet the requirements established by CCNR stage I, the
emission limit values for which are set out in Annex XIV.
(3) As from the 1 st July 2007 and until the entry into
force of a further set of limit values which would result from
further amendments to these regulations, the competent
authority may not refuse the placing on the market of engines
which meet the requirements established by CCNR stage II,
the emission limit values for which are set out in Annex XV.
(4) Annex VII shall be adapted to integrate the
additional and specific information, which may be required
as regards the type approval certificate for engines to be
installed in inland waterway vessels.
(5) For the purposes of these regulations, as far as
inland waterway vessels are concerned, any auxiliary engine
with a power of more than 560 kW shall be subject to the
same requirements as propulsion engines.”.
Regulation 7 shall be amended as follows>
(a) For sub-regulation (1) thereof, there shall be replaced
the following>
“(1) The competent authority may not refuse the
placing on the market of engines, whether or not already
installed in machinery, which meet the requirements of these
regulations.”< and
(b) Immediately after sub-regulation (2) thereof, there shall
be added the following new sub-regulation>
“(2A) The competent authority shall not issue the
Community Inland Water Navigation certificate established
by Council Directive 82#714#EC of 4 October 1982 laying
down technical requirements for inland waterway vessels to
any vessels whose engines do not meet the requirements of
these regulations.”.
Amends regulation
Regulation 8 shall be amended as follows>
(1) Il-provvedimenti ta’ dan ir-regolament
g[andhom japplikaw g[all-magni li se ji;u nstallati
f’bastimenti tal-kanali interni>
I]da s-subregolamenti (2) u (3) m’g[andhomx
japplikaw sakemm l-ekwivalenza bejn il-[ti;ijiet stabbiliti
minn dawn ir-regolamenti u dawk stabbiliti fil-qafas tal-
Konvenzjoni ta’ Mannheim g[at-Tba[[ir tar-Rhine ti;i
rikonoxxuta mill-Kummissjoni ?entrali tat-Tba[[ir tar-Rhine
(hawn aktar ’il quddiem imsejj[a> CCNR) u l-Kummissjoni
ti;i nformata b’dan.
(2) Sat-30 ta’ :unju 2007, l-awtorità kompetenti
ma tistax tirrifjuta t-tqeg[id fis-suq ta’ magni li jkunu
jissodisfaw il-[ti;ijiet stabbiliti mill-istadju I tas-CCNR li l-
valuri tal-limitu ta’ l-emissjonijiet tag[hom huma stipulati
fl-Anness XIV.
(3) Mill-1 ta’ Lulju 2007 sad-d[ul fis-se[[ ta’ sett
ie[or ta’ valuri ta’ limitu li jirri]ulta minn emendi sussegwenti
g[al dawn ir-regolamenti, l-awtorità kompetenti ma tistax
tirrifjuta t-tqeg[id fis-suq ta’ magni li jissodisfaw il-[ti;ijiet
stabbiliti mill-istadju II tas-CCNR, li l-valuri tal-limitu ta’ l-
emissjonijiet tag[hom huma stipulati fl-Anness XV.
(4) L-Anness VII g[andu ji;i adattat sabiex
jintegra l-informazzjoni addizjonali jew speçifika, li tista’ tkun
me[tie;a fir-rigward taç-çertifikat ta’ l-approvazzjoni tat-tip
g[all-magni li se ji;u nstallati f’bastimenti tal-kanali interni.
(5) G[all-g[anijiet ta’ dawn ir-regolamenti, f’dak
li jirrigwarda l-bastimenti tal-kanali interni, kull magna
aw]iljarja b’forza ta’ i]jed minn 560 kW g[andha tkun
so;;etta g[all-istess [ti;ijiet b[all-magni li ja[dmu bil-
propulsjoni.”.
6. Ir-regolament 7 tar-regolamenti prinçipali g[andu ji;i emendat
(a)
minflok is-subregolament (1) g[andu jid[ol dan li ;ej>
“(1) L-awtorità kompetenti ma tistax tirrifjuta t-tqeg[id
fis-suq ta’ magni, kemm jekk di;à installati fil-magni kemm
jekk le, li jissodisfaw il-[ti;ijiet ta’ dawn ir-regolamenti.”< u
(b) minnufih wara s-subregolament (2) g[andu jid[ol dan
is-subregolament ;did li ;ej>
“(2A) L-awtorità kompetenti m’g[andhiex to[ro; iç-
çertifikat Komunitarju tat-Tba[[ir ta’ l-Ilmijiet Interni stabbilit
mid-Direttiva tal-Kunsill 82#714#KE ta’ l-4 ta’ Ottubru 1982
li jistipula l-[ti;ijiet tekniçi g[all-bastimenti ta’ tba[[ir tal-
kanali interni li l-magni tag[hom ma jkunux konformi mal-
[ti;ijiet ta’ dawn ir-regolamenti.”.
8 of the principal
regulations.
(a) in sub-regulation (3) thereof, for the words “The
competent authority shall” to the words “an engine is installed” in
the first paragraph thereof, there shall be substituted the following>
“The competent authority shall refuse to grant type
approval for an engine type or engine family and to issue the
document as described in Annex VII and shall refuse to grant
any other type-approval for non-road mobile machinery, in
which an engine, not already placed on the market, is
installed<”<
(b) immediately after sub-regulation (3) thereof, there shall
be added the following new sub-regulation>-
“3A. TYPE-APPROVAL OF STAGE IIIA ENGINES
(ENGINE CATEGORIES H, I, J and K)
The competent authority shall refuse to grant type-
approval for the following engine types or families and to
issue the document as described in Annex VII, and shall refuse
to grant any other type-approval for non-road mobile
machinery in which an engine, not already placed on the
market, is installed>
– H> after 30 June 2005 for engines – other than
constant speed engines – of a power output> 130 kW X
P X 560 kW,
– I> after 31 December 2005 for engines – other
than constant speed engines – of a power output> 75 kW
X P < 130 kW,
– J> after 31 December 2006 for engines – other
than constant speed engines – of a power output> 37kW
X P < 75 kW,
– K> after 31 December 2005 for engines – other
than constant speed engines – of a power output> 19 kW
X P < 37 kW,
where the engine fails to meet the requirements
specified in these regulations and where the emissions
of particulate and gaseous pollutants from the engine do
not comply with the limit values as set out in the table in
section 4.1.2.4. of Annex I.
3B. TYPE-APPROVAL OF STAGE IIIA
CONSTANT SPEED ENGINES (ENGINE CATEGORIES
H, I, J and K)
The competent authority shall refuse to grant type-
approval for the following engine types or families and to
issue the document as described in Annex VII, and shall refuse
to grant any other type-approval for non-road mobile
machinery in which an engine, not already placed on the
market, is installed>
– Constant speed H engines> after 31 December
2009 for engines of a power output> 130 kW X P < 560
kW,
– Constant speed I engines> after 31 December
2009 for engines of a power output> 75 kW X P < 130
kW,
– Constant speed J engines> after 31 December
2010 for engines of a power output> 37 kW X P < 75
kW,
– Constant speed K engines> after 31 December
2009 for engines of a power output> 19 kW X P < 37
kW,
where the engine fails to meet the requirements specified
in these regulations and where the emissions of
particulate and gaseous pollutants from the engine do
not comply with the limit values set out in the table in
Section 4.1.2.4. of Annex I.
3C. TYPE-APPROVAL OF STAGE III B ENGINES
(ENGINE CATEGORIES L, M, N and P)
The competent authority shall refuse to grant type-
approval for the following engine types or families and to
issue the document as described in Annex VII, and shall refuse
to grant any other type-approval for non-road mobile
machinery in which an engine, not already placed on the
market, is installed>
– L> after 31 December 2009 for engines – other
than constant speed engines – of a power output> 130
kW X P X 560 kW,
– M> after 31 December 2010 for engines – other
than constant speed engines – of a power output> 75 kW
X P < 130 kW,
– N> after 31 December 2010 for engines – other
than constant speed engines – of a power output> 56 kW
X P < 75 kW,
– P> after 31 December 2011 for engines – other
than constant speed engines – of a power output> 37 kW
X P < 56 kW,
where the engine fails to meet the requirements
specified in these regulations and where the emissions
of particulate and gaseous pollutants from the engine do
not comply with the limit values set out in the table in
Section 4.1.2.5. of Annex I.
3D. TYPE-APPROVAL OF STAGE IV ENGINES
(ENGINE CATEGORIES Q and R)
The competent authority shall refuse to grant type-
approval for the following engine types or families and to
issue the document as described in Annex VII, and shall refuse
to grant any other type-approval for non-road mobile
machinery in which an engine, not already placed on the
market, is installed>
– Q> after 31 December 2012 for engines – other
than constant speed engines – of a power output> 130
kW X P X 560 kW,
– R> after 30 September 2013 for engines – other
than constant speed engines – of a power output> 56 kW
X P < 130 kW,
where the engine fails to meet the requirements
specified in these regulations and where the emissions
of particulate and gaseous pollutants from the engine do
not comply with the limit values set out in the table in
Section 4.1.2.6. of Annex I.
3E. TYPE-APPROVAL OF STAGE III A
PROPULSION ENGINES USED IN INLAND
WATERWAY VESSELS (ENGINE CATEGORIES V)
The competent authority shall refuse to grant type-
approval for the following engine types or families and to
issue the document as described in Annex VII>
V1>1> after 31 December 2005 for engines of power
output at or above 37 kW and swept volume below 0.9
litres per cylinder,
V1>2> after 30 June 2005 for engines with swept
volume at or above 0.9 but below 1.2 litres per cylinder,
V1>3> after 30 June 2005 for engines with swept
volume at or above 1.2 but below 2.5 litres per cylinder
and an engine power output of> 37 kW X P < 75 kW,
V1>4> after 31 December 2006 for engines with
swept volume at or above 2.5 but below 5 litres per
cylinder,
V2> after 31 December 2007 for engines with swept
volume at or above 5 litres per cylinder,
where the engine fails to meet the requirements specified
in these regulations and where the emissions of
particulate and gaseous pollutants from the engine do
not comply with the limit values as set out in the table in
section 4.1.2.4. of Annex I.
3F. TYPE-APPROVAL OF STAGE III A
PROPULSION ENGINES USED IN RAILCARS
The competent authority shall refuse to grant type-
approval for the following engine types or families and to
issue the document as described in Annex VII>
– RC A> after 30 June 2005 for engines of power
output above 130 kW,
where the engine fails to meet the requirements specified
in these regulations and where the emissions of
particulate and gaseous pollutants from the engine do
not comply with the limit values as set out in the table in
section 4.1.2.4. of Annex I.
3G. TYPE-APPROVAL OF STAGE III B
PROPULSION ENGINES USED IN RAILCARS
The competent authority shall refuse to grant type-
approval for the following engine types or families and to
issue the document as described in Annex VII>
– RC B> after 31 December 2010 for engines of
power output above 130 kW,
where the engine fails to meet the requirements specified
in these regulations and where the emissions of
particulate and gaseous pollutants from the engine do
not comply with the limit values as set out in the table in
section 4.1.2.5. of Annex I.
3H. TYPE-APPROVAL OF STAGE III A
PROPULSION ENGINES USED IN LOCOMOTIVES
The competent authority shall refuse to grant type-
approval for the following engine types or families and to
issue the document as described in Annex VII>
– RL A> after 31 December 2005 for engines of
power output> 130 kW X P X 560 kW,
– RH A> after 31 December 2007 for engines of
power output> 560 kW < P,
where the engine fails to meet the requirements
specified in these regulations and where the emissions
of particulate and gaseous pollutants from the engine do
not comply with the limit values as set out in the table in
section 4.1.2.4. of Annex I. The provisions of this sub-
regulation shall not apply to the engine types and families
referred to where a contract has been entered into to
purchase the engine before the coming into force of these
regulations and provided that the engine is placed on
the market not later than two years after the applicable
date for the relevant category of locomotives.
3I. TYPE-APPROVAL OF STAGE III
B
PROPULSION ENGINES USED IN LOCOMOTIVES
The competent authority shall refuse to grant type-
approval for the following engine types or families and to
issue the document as described in Annex VII>
– R B> after 31 December 2010 for engines of
power output above 130 kW,
where the engine fails to meet the requirements specified
in these regulations and where the emissions of
particulate and gaseous pollutants from the engine do
not comply with the limit values as set out in the table in
section 4.1.2.5. of Annex I. The provisions of this sub-
regulation shall not apply to the engine types and families
referred to where a contract has been entered into to
purchase the engine before the coming into force of these
regulations and provided that the engine is placed on
the market not later than two years after the applicable
date for the relevant category of locomotives.”<
(c) Immediately after sub-regulation (4) thereof, there shall
be added the following new sub-regulation>–
4A. For engine types or engine families meeting the
compliance limit values set out in the table in section 4.1.2.4., 4.1.2.5.
and 4.1.2.6. of Annex I before the dates laid down in paragraph
stages IIIA, 4 of this regulation, the competent authority shall allow special
labelling and marking to show that the equipment concerned
meets the required limit values before the dates laid down.”<
and
(d) immediately after sub-regulation (5) thereof, there shall
be added the following new sub-regulation>
“5A. Without prejudice to regulation 6A and to
regulation 8 (3G) and (3H), after the dates referred to hereafter,
with the exception of machinery and engines intended for
export to third countries, the competent authority shall permit
the placing on the market of engines, whether or not already
installed in machinery, only if they meet the requirements of
these regulations, and only if the engine is approved in
compliance with one of the categories as defined in sub-
regulations (2) and (3).
Stage III A other than constant speed engines
– category H> 31 December 2005
– category I> 31 December 2006
– category J> 31 December 2007
– category K> 31 December 2006
Stage III A inland waterway vessel engines
– category V1>1> 31 December 2006
– category V1>2> 31 December 2006
– category V1>3> 31 December 2006
– category V1>4> 31 December 2008
– categories V2> 31 December 2008
Stage III A constant speed engines
– category H> 31 December 2010
– category I> 31 December 2010
– category J> 31 December 2011
– category K> 31 December 2010
Stage III A railcar engines
– category RC A> 31 December 2005
Stage III A locomotive engines
– category RL A>31 December 2006
– category RH A>31 December 2008
Stage III B other than constant speed engines
– category L> 31 December 2010
– category M> 31 December 2011
– category N> 31 December 2011
– category P> 31 December 2012
Stage III B railcar engines
– category RC B> 31 December 2011
Stage III B locomotive engines
– category R B> 31 December 2011
Stage IV other than constant speed engines
– category Q> 31 December 2013
– category R> 30 September 2014
For each category, the above requirements shall be
postponed by two years in respect of engines with a production
date prior to the said date. The permission granted for one
stage of emission limit values shall be terminated with effect
from the mandatory implementation of the next stage of limit
values.”.
Regulation 9 of the principal regulations shall be amended as
(a) For sub-regulation (1) there shall be substituted the
following>
“(1) The requirements of regulation 7(1) and (2),
regulation 8(4) and regulation 8 (5) shall not apply to>
– engines for use by the armed services,
– engines exempted in accordance with sub-
regulations (1) and (2),
– engines for use in machines intended primarily
for the launch and recovery of lifeboats,
– engines for use in machines intended primarily
for the launch and recovery of beach launched vessels.
1A. Without prejudice to regulation 6A and to
regulation 8(3G) and (3H), replacement engines, except for
railcar, locomotive and inland waterway vessel propulsion
engines, shall comply with the limit values that the engine to
be replaced had to meet when originally placed on the market.
The text “REPLACEMENT ENGINE” shall be attached to a
label on the engine or inserted into the owner’s manual.”<
and
(b) immediately after sub-regulation (2), there shall be added
the following new sub-regulation>
“(3) Engines may be placed on the market under a
flexible scheme in accordance with the provisions in Annex
XIII.
(4) Sub-regulation (2) shall not apply to propulsion
engines to be installed in inland waterway vessels.
(5) The competent authority shall permit the placing
on the market of engines, as defined under A(i) and A(ii) of
Annex I, under the flexibility scheme in accordance with the
provisions in Annex XIII.”.
The Annexes to the principal regulations shall be amended as Amends Annexes to
the principal
regulations.
ANNEX I
1. ANNEX I SHALL BE AMENDED AS FOLLOWS
SECTION 1 SHALL BE AMENDED AS FOLLOWS
(a)
Point A shall be replaced by the following
intended and suited, to move, or to be moved with or without road, and with
(i)
a C.I. engine having a net power in accordance with section 2.4 that is higher than or equal to 19 kW
but not more than 560 kW and that is operated under intermittent speed rather than a single constant
speed;
(ii)
a C.I. engine having a net power in accordance with section 2.4 that is higher than or equal to 19 kW
but not more than 560 kW and that is operated under constant speed. Limits only apply from
31 December 2006;
(iii)
a petrol fuelled S.I. engine having a net power in accordance with section 2.4 of not more than 19
kW;
(iv)
engines designed for the propulsion of railcars, which are self propelled on-track vehicles specifically
designed to carry goods and/or passengers;
(v)
engines designed for the propulsion of locomotives which are self-propelled pieces of on-track
equipment designed for moving or propelling cars that are designed to carry freight, passengers and
other equipment, but which themselves are not designed or intended to carry freight, passengers
(other than those operating the locomotive) or other equipment. Any auxiliary engine or engine
intended to power equipment designed to perform maintenance or construction work on the tracks is
not classified under this paragraph but under A(i).";
(b)
Point B shall be replaced by the following
""B. Ships, except vessels intended for use on inland waterways";
(c)
Point C shall be deleted
Section 2 shall be amended as follows
(a)
The following shall be inserted
volume of 100m 3 or more with regard to a vessel intended for use on inland waterways means its
volume calculated on the formula LxBxT, "L" being the maximum length of the hull, excluding
rudder and bowsprit, "B" being the maximum breadth of the hull in metres, measured to the outer
edge of the shell plating (excluding paddle wheels, rubbing strakes, etc.) and "T" being the vertical
distance between the lowest moulded point of the hull or the keel and the maximum draught line.
valid navigation or safety certificate shall mean
(a)
a certificate proving conformity with the 1974 International Convention for the Safety of Life
at Sea (SOLAS), as amended, or equivalent, or
(b)
a certificate proving conformity with the 1966 International Convention on Load Lines, as
amended, or equivalent, and an IOPP certificate proving conformity with the 1973
International Convention for the Prevention of Pollution from Ships (MARPOL), as amended.
Defeat device shall mean a device which measures, senses or responds to operating variables for the
purpose of activating, modulating, delaying or deactivating the operation of any component or
function of the emission control system such that the effectiveness of the control system is reduced
under conditions encountered during the normal non-road mobile machinery use unless the use of
such a device is substantially included in the applied emission test certification procedure.
Irrational control strategy shall mean any strategy or measure that, when the non-road mobile
machinery is operated under normal conditions of use, reduces the effectiveness of the emission
control system to a level below that expected in the applicable emission test procedures."
(b)
The following section shall be inserted
test cycle shall mean a sequence of test points, each with a defined speed and torque, to be followed
by the engine under steady state (NRSC test) or transient operating conditions (NRTC test);"
(c)
Current Section 2.17 shall be renumbered 2.18 and be replaced by the following
Symbols and abbreviations
Symbols for test parameters
Term
Stoichiometric air/fuel ratio
Cross sectional area of the isokinetic sampling probe
Cross sectional area of the exhaust pipe
Weighted average values for
– volume flow
– mass flow
Carbon 1 equivalent hydrocarbon
Discharge coefficient of the SSV
Concentration (with suffix of the component nominating)
Background corrected concentration
Concentration of the pollutant measured in the dilution air
Concentration of the pollutant measured in the diluted exhaust gas
Diameter
Dilution factor
Laboratory atmospheric factor
Intake air mass flow rate on dry basis
Intake air mass flow rate on wet basis
Dilution air mass flow rate on wet basis
Equivalent diluted exhaust gas mass flow rate on wet basis
Exhaust gas mass flow rate on wet basis
Fuel mass flow rate
Sampled exhaust mass flow rate
Tracer gas flow rate
Diluted exhaust gas mass flow rate on wet basis
Absolute humidity of the intake air
Absolute humidity of the dilution air
Reference value of absolute humidity (10,71 g/kg)
Term
Subscript denoting an individual mode (for NRSC test)or an instananeous value (for NRTC test)
Humidity correction factor for NO x
Humidity correction factor for particulate
CFV calibration function
Dry to wet correction factor for the intake air
Dry to wet correction factor for the dilution air
Dry to wet correction factor for the diluted exhaust gas
Dry to wet correction factor for the raw exhaust gas
Percent torque related to the maximum torque for the test speed
Particulate sample mass of the dilution air collected
Mass of the dilution air sample passed through the particulate sampling filters
Mass of equivalent diluted exhaust gas over the cycle
Total exhaust mass flow over the cycle
Particulate sample mass collected
Particulate sample mass collected on primary filter
Particulate sample mass collected on back-up filter
Total mass of gaseous pollutant over the cycle
Total mass of particulate over the cycle
Mass of the diluted exhaust sample passed through the particulate sampling filters
Sampled exhaust mass over the cycle
Mass of secondary dilution air
Total mass of double diluted exhaust over the cycle
Total mass of diluted exhaust gas passing the dilution tunnel over the cycle on wet basis
Instantaneous mass of diluted exhaust gas passing the dilution tunnel on wet basis
Subscript denoting emissions mass flow (rate)
Total revolutions of PDP over the cycle
Reference engine speed for NRTC test
Derivative of the engine speed
Power, brake uncorrected
Pressure drop below atmospheric at the pump inlet of PDP
Absolute pressure
Saturation vapour pressure of the engine intake air
(ISO 3046: ps y =PSY test ambient)
Declared total power absorbed by auxiliaries fitted for the test which are not required by
paragraph 2.4 of this Annex
Total atmospheric pressure (ISO 3046
P x =PX Site ambient total pressure
P y =PY Test ambient total pressure)
Saturation vapour pressure of the dilution air
Maximum power at the test speed under test conditions (see Annex VII, Appendix 1)
Power measured on test bed
Dry atmospheric pressure
Dilution ratio
CVS volume flow rate
Ratio of the SSV throat to inlet absolute, static pressure
Symbol
Unit
Term
r
Ratio of cross sectional areas of isokinetic probe and exhaust pipe
R a
%
Relative humidity of the intake air
R d
%
Relative humidity of the dilution air
Re
-
Reynolds number
R f
-
FID response factor
T
K
Absolute temperature
t
s
Measuring time
T a
K
Absolute temperature of the intake air
T D
K
Absolute dew point temperature
T ref
K
Reference temperature of combustion air: (298 K)
T sp
N·m
Demanded torque of the transient cycle
t 10
s
Time between step input and 10% of final reading
t 50
s
Time between step input and 50% of final reading
t 90
s
Time between step input and 90% of final reading
∆t i
s
Time interval for instantaneous CFV flow
m³/rev
PDP volume flow rate at actual conditions
W act
kWh
Actual cycle work of NRTC
WF
-
Weighting factor
WF E
-
Effective weighting factor
m³/rev
Calibration function of PDP volume flow rate
kg·m 2
Θ D
Rotational inertia of the eddy-current dynamometer
ß
-
Ratio of the SSV throat diameter, d, to the inlet pipe inner diameter
-
Relative air/fuel ratio, actual A/F divided by stoichiometric A/F
"
kg/m³
Density of the exhaust gas
" EXH
2.18.2. Symbols for chemical components
CH 4
Methane
C 3 H 8
Propane
C 2 H 6
Ethane
CO
Carbon monoxide
CO 2
Carbon dioxide
DOP
Di-octylphthalate
H 2 O
Water
HC
Hydrocarbons
NOx
Oxides of nitrogen
NO
Nitric oxide
NO 2
Nitrogen dioxide
Oxygen
PT
Particulates
PTFE
Polytetrafluoroethylene
2.18.3. Abbreviations
CFV
Critical Flow Venturi
CLD
Chemiluminescent detector
CI
Compression Ignition
FID
Flame Ionisation Detector
FS
Full scale
HCLD
Heated Chemiluminescent Detector
HFID
Heated Flame Ionisation Detector
NDIR
Non-Dispersive Infrared Analyser
NG
Natural Gas
NRSC
Non-Road Steady Cycle
NRTC
Non-Road Transient Cycle
PDP
Positive Displacement Pump
SI
Spark Ignition
SSV
Sub-Sonic Venturi"
Section 3 shall be amended as follows
(a)
The following section shall be inserted
"3.1.4.
labels in accordance with Annex XIII, if the engine is placed on the market under flexible scheme
provisions."
Section 4 is amended as follows
(a)
At the end of section 4.1.1. the following shall be added
"All engines that expel exhaust gases mixed with water shall be equipped with a connection in the engine exhaust
system that is located downstream of the engine and before any point at which the exhaust contacts water (or any
other cooling/scrubbing medium) for the temporary attachment of gaseous or particulate emissions sampling
equipment. It is important that the location of this connection allows a well mixed representative sample of the
exhaust. This connection shall be internally threaded with standard pipe threads of a size not larger than one-half
inch, and shall be closed by a plug when not in use (equivalent connections are allowed)."
(b)
The following section shall be added
"4.1.2.4.
The emissions of carbon monoxide, the emissions of the sum of hydrocarbons and oxides of nitrogen
and the emissions of particulates shall for stage III A not exceed the amounts shown in the table
below
Engines for use in other applications than propulsion of inland waterway vessels, locomotives and railcars
Category: Net power
Carbon monoxide
Sum of hydrocarbons and oxides of
Particulates
(CO)
nitrogen
(PT)
(g/kWh)
(HC+NOx)
(g/kWh)
(g/kWh)
H: 130 kW ≤ P ≤ 560 kW
3,5
4,0
0,2
I: 75 kW ≤ P < 130 kW
5,0
4,0
0,3
J: 37 kW ≤ P <75 kW
5,0
4,7
0,4
K: 19 kW ≤ P <37 kW
5,5
7,5
0,6
Engines for propulsion of inland waterway vessels
Category: swept volume/net power
Carbon monoxide
Sum of hydrocarbons and oxides of
Particulates
(CO)
nitrogen
(PT)
(g/kWh)
(HC+NOx)
(g/kWh)
(g/kWh)
5.0
7.5
0.40
5.0
7.2
0.30
5.0
7.2
0.20
5.0
7.2
0.20
5.0
7.8
0.27
5.0
8.7
0.50
5.0
9.8
0.50
5,0
9.8
0.50
5,0
0
0.50
Engines for propulsion of locomotives
Carbon monoxide
Sum of hydrocarbons and oxides of
Particulates
(CO)
nitrogen
(PT)
(g/kWh)
(HC+NOx)
(g/kWh)
(g/kWh)
RL A: 130 kW ≤ P ≤ 560 kW
3,5
4,0
0,2
Carbon monoxide
Hydrocarbons
Oxides of
Particulates
(CO)
(HC)
nitrogen
(PT)
(g/kWh)
(g/kWh)
(NOx)
(g/kWh)
(g/kWh)
3,5
0,5
6,0
0,2
RH A Engines with P > 2000 kW and
3,5
0,4
7,4
0,2
Engines for propulsion of railcars
Category: net power (P) (kW)
Carbon monoxide
Sum of hydrocarbons and oxides of
Particulates
(CO)
nitrogen
(PT)
(g/kWh)
(HC+NOx)
(g/kWh)
(g/kWh)
3,5
4,0
0,20
"
(c)
The following section shall be inserted
The emissions of carbon monoxide, the emissions of hydrocarbons and oxides of nitrogen (or their
sum where relevant) and the emissions of particulates shall, for stage III B, not exceed the amounts
shown in the table below
Engines for use in other applications than propulsion of locomotives,
railcars and inland waterway vessels
Carbon monoxide
Hydrocarbons
Oxides of
Particulates
(CO)
(HC)
nitrogen
(PT)
(g/kWh)
(g/kWh)
(Nox)
(g/kWh)
(g/kWh)
3,5
0,19
2,0
0,025
5,0
0,19
3,3
0,025
5,0
0,19
3,3
0,025
Sum of hydrocarbons and oxides
ofnitrogen
(HC+NOx)
(g/kWh)
5,0
4,7
0,025
Engines for propulsion of railcars
Category: net power (P) (kW)
Carbon monoxide
Hydrocarbons
Oxides of
Particulates
(CO)
(HC)
nitrogen
(PT)
(g/kWh)
(g/kWh)
(NOx)
(g/kWh)
(g/kWh)
3,5
0.19
2,0
0,025
Engines for propulsion of locomotives
Carbon monoxide
Sum of hydrocarbons and oxides of
Particulates
(CO)
nitrogen
(PT)
(g/kWh)
(HC+NOx)
(g/kWh)
(g/kWh)
3,5
4,0
0,025
(d)
The following section shall be inserted after the new section 4.1.2.5
The emissions of carbon monoxide, the emissions of hydrocarbons and oxides of nitrogen (or their
sum where relevant) and the emissions of particulates shall for stage IV not exceed the amounts
shown in the table below
Engines for use in other applications than propulsion of locomotives,
railcars and inland waterway vessels
Carbon monoxide
Hydrocarbons
Oxides of
Particulates
(CO)
(HC)
nitrogen
(PT)
(g/kWh)
(g/kWh)
(NOx) (g/kWh)
(g/kWh)
3,5
0,19
0,4
0,025
5,0
0,19
0,4
0,025
(e)
The following section shall be inserted
The limit values in sections 4.1.2.4, 4.1.2.5 and 4.1.2.6 shall include deterioration calculated in
accordance with Annex III, appendix 5.
In the case of limit values standards contained in sections 4.1.2.5 and 4.1.2.6, under all randomly
selected load conditions, belonging to a definite control area and with the exception of specified
engine operating conditions which are not subject to such a provision, the emissions sampled during a
time duration as small as 30 s shall not exceed by more than 100% the limit values of the above
tables. The control area to which the percentage not to be exceeded shall apply and the excluded
engine operating conditions shall be defined in accordance with the procedure referred to in Article
15."
(f)
Section 4.1.2.4 shall be renumbered to 4.1.2.8
2. ANNEX III SHALL BE AMENDED AS FOLLOWS
Section 1 shall be amended as follows
(a)
The following shall be added to section 1.1.
"Two test cycles are described that shall be applied according to the provisions of Annex I, Section 1
the NRSC (Non-Road Steady Cycle) which shall be used for stages I, II and IIIA and for constant speed
engines as well as for stages IIIB and IV in the case of gaseous pollutants,
the NRTC (Non-Road Transient Cycle) which shall be used for the measurement of particulate emissions for
stages IIIB and IV and for all engines but constant speed engines. By the choice of the manufacturer this test
can be used also for stage IIIA and for the gaseous pollutants in stages IIIB and IV.
For engines intended to be used in inland waterway vessels the ISO test procedure as specified by ISO 8178-
4:2002 [E] and IMO MARPOL 73/78, Annex VI (NOx Code) shall be used.
For engines intended for propulsion of railcars an NRSC shall be used for the measurement of gaseous and
particulate pollutants for stage III A and for stage III B.
For engines intended for propulsion of locomotives an NRSC shall be used for the measurement of gaseous
and particulate pollutants for stage III A and for stage III B."
(b)
The following section shall be added
Measurement principle
The engine exhaust emissions to be measured include the gaseous components (carbon monoxide, total
hydrocarbons and oxides of nitrogen), and the particulates. Additionally, carbon dioxide is often used as a
tracer gas for determining the dilution ratio of partial and full flow dilution systems. Good engineering
practice recommends the general measurement of carbon dioxide as an excellent tool for the detection of
measurement problems during the test run.
1.3.1. NRSC Test
During a prescribed sequence of operating conditions, with the engines warmed up, the amounts of the above
exhaust emissions shall be examined continuously by taking a sample from the raw exhaust gas. The test
cycle consists of a number of speed and torque (load) modes, which cover the typical operating range of
diesel engines. During each mode, the concentration of each gaseous pollutant, exhaust flow and power
output shall be determined, and the measured values weighted. The particulate sample shall be diluted with
conditioned ambient air. One sample over the complete test procedure shall be taken and collected on
suitable filters.
Alternatively, a sample shall be taken on separate filters, one for each mode, and cycle-weighted results
computed.
The grams of each pollutant emitted per kilowatt -hour shall be calculated as described in Appendix 3 to this
Annex.
1.3.2. NRTC Test
The prescribed transient test cycle, based closely on the operating conditions of diesel engines installed in
non-road machinery, is run twice
–
The first time (cold start) after the engine has soaked to room temperature and the engine coolant and
oil temperatures, after treatment systems and all auxiliary engine control devices are stabilised
between 20 and 30°C.
–
The second time (hot start) after a twenty-minute hot soak that commences immediately after the
completion of the cold start cycle.
During this test sequence the above pollutants shall be examined. Using the engine torque and speed
feedback signals of the engine dynamometer, the power shall be integrated with respect to the time of the
cycle, resulting in the work produced by the engine over the cycle. The concentrations of the gaseous
components shall be determined over the cycle, either in the raw exhaust gas by integration of the analyzer
signal in accordance with Appendix 3 to this Annex, or in the diluted exhaust gas of a CVS full-flow dilution
system by integration or by bag sampling in accordance with Appendix 3 to this Annex. For particulates, a
proportional sample shall be collected from the diluted exhaust gas on a specified filter by either partial flow
dilution or full-flow dilution. Depending on the method used, the diluted or undiluted exhaust gas flow rate
shall be determined over the cycle to calculate the mass emission values of the pollutants. The mass emission
values shall be related to the engine work to give the grams of each pollutant emitted per kilowatt-hour.
Emissions (g/kWh) shall be measured during both the cold and hot start cycles. Composite weighted
emissions shall be computed by weighting the cold start results 10% and the hot start results 90%. Weighted
composite results shall meet the standards.
Prior to the introduction of the cold/hot composite test sequence, the symbols (Annex I, section 2.18) the test
sequence (Annex III) and calculation equations (Annex III, Appendix III) shall be modified in accordance
with the procedure referred to in Article 15."
Section 2 shall be amended as follows
(a)
Section 2.2.3 shall be replaced by the following
"2.2.3. Engines with charge air cooling
The charge air temperature shall be recorded and, at the declared rated speed and full load, shall be
within # 5 K of the maximum charge air temperature specified by the manufacturer. The temperature
of the cooling medium shall be at least 293 K (20°C).
If a test shop system or external blower is used, the charge air temperature shall be set to within # 5
K of the maximum charge air temperature specified by the manufacturer at the speed of the declared
maximum power and full load. Coolant temperature and coolant flow rate of the charge air cooler
at the above set point shall not be changed for the whole test cycle. The charge air cooler volume
shall be based upon good engineering practice and typical vehicle/machinery applications.
Optionally, the setting of the charge air cooler may be done in accordance with SAE J 1937 as
published in January 1995."
(b)
The text under section 2.3 shall be replaced by the following
"The test engine shall be equipped with an air inlet system presenting an air inlet restriction within # 300 Pa of the
value specified by the manufacturer for a clean air cleaner at the engine operating conditions as specified by the
manufacturer, which result in maximum air flow. The restrictions are to be set at rated speed and full load. A test
shop system may be used, provided it duplicates actual engine operating conditions."
(c)
The text under section 2.4 Engine exhaust system shall be replaced by the following
"The test engine shall be equipped with an exhaust system with exhaust back pressure within # 650 Pa of the value
specified by the manufacturer at the engine operating conditions resulting in maximum declared power.
If the engine is equipped with an exhaust after-treatment device, the exhaust pipe shall have the same diameter as
found in-use for at least 4 pipe diameters upstream to the inlet of the beginning of the expansion section containing
the after-treatment device. The distance from the exhaust manifold flange or turbocharger outlet to the exhaust after-
treatment device shall be the same as in the machine configuration or within the distance specifications of the
manufacturer. The exhaust backpressure or restriction shall follow the same criteria as above, and may be set with a
valve. The aftertreatment container may be removed during dummy tests and during engine mapping, and replaced
with an equivalent container having an inactive catalyst support."
(d)
Section 2.8 shall be deleted.
Section 3 shall be amended as follows
(a)
The title of section 3 shall be replaced by
"3.
TEST RUN (NRSC TEST)"
(b)
The following section shall be inserted
"3.1.
Determination of dynamometer settings
The basis of specific emissions measurement is uncorrected brake power according to ISO 14396: 2002.
Certain auxiliaries, which are necessary only for the operation of the machine and may be mounted on the
engine, should be removed for the test. The following incomplete list is given as an example
–
air compressor for brakes
–
power steering compressor
–
air conditioning compressor
–
pumps for hydraulic actuators.
Where auxiliaries have not been removed, the power absorbed by them at the test speeds shall be determined in order
to calculate the dynamometer settings, except for engines where such auxiliaries form an integral part of the engine
(e.g. cooling fans for air cool engines).
The settings of inlet restriction and exhaust pipe backpressure shall be adjusted to the manufacturer's upper limits, in
accordance with sections 2.3 and 2.4.
The maximum torque values at the specified test speeds shall be determined by experimentation in order to calculate
the torque values for the specified test modes. For engines which are not designed to operate over a range on a full
load torque curve, the maximum torque at the test speeds shall be declared by the manufacturer.
The engine setting for each test mode shall be calculated using the formula
L %
"
S * # " P M ( P AE # x
& ) P AE
100 '
$
If the ratio,
P AE
" 0 , 03
P M
the value of P AE may be verified by the technical authority granting type approval."
(c)
Current sections 3.1 – 3.3 shall be renumbered 3.2 – 3.4
(d)
Current section 3.4 shall be renumbered 3.5 and replaced by the following
Adjustment of the dilution ratio
The particulate sampling system shall be started and running on bypass for the single filter method (optional
for the multiple filter method). The particulate background level of the dilution air may be determined by
passing dilution air through the particulate filters. If filtered dilution air is used, one measurement may be
done at any time prior to, during, or after the test. If the dilution air is not filtered, the measurement must be
done on one sample taken for the duration of the test.
The dilution air shall be set to obtain a filter face temperature between 315 K (42°C) and 325 K (52°C) at
each mode. The total dilution ratio shall not be less than four.
NOTE: For steady-state procedure, the filter temperature may be kept at or below the maximum temperature
of 325 K (52°C) instead of respecting the temperature range of 42°C – 52°C.
For the single and multiple filter methods, the sample mass flow rate through the filter shall be maintained at
a constant proportion of the dilute exhaust mass flow rate for full flow systems for all modes. This mass ratio
shall be within ± 5% with respect to the averaged value of the mode, except for the first 10 seconds of each
mode for systems without bypass capability. For partial flow dilution systems with single filter method, the
mass flow rate through the filter shall be constant within ± 5% with respect to the averaged value of the
mode, except for the first 10 seconds of each mode for systems without bypass capability.
For CO 2 or NOx concentration controlled systems, the CO 2 or NOx content of the dilution air must be
measured at the beginning and at the end of each test. The pre and post test background CO 2 or NOx
concentration measurements of the dilution air must be within 100 ppm or 5 ppm of each other, respectively.
When using a dilute exhaust gas analysis system, the relevant background concentrations shall be determined
by sampling dilution air into a sampling bag over the complete test sequence.
Continuous (non-bag) background concentration may be taken at the minimum of three points, at the
beginning, at the end, and a point near the middle of the cycle and averaged. At the manufacturer's request
background measurements may be omitted."
(e)
Current sections 3.5-3.6 shall be renumbered 3.6-3.7.
(f)
Current sections 3.6.1 shall be replaced by the following
"3.7.1. Equipment specification according to Section 1A of Annex I
3.7.1.1. Specification A.
For engines covered by Section 1A(i) and A(iv) of Annex I, the following 8-mode cycle 1 shall be
followed in dynamometer operation on the test engine
Mode Number
Engine Speed
Load
Weighting Factor
Rated
0,15
Rated
0,15
Rated
0,15
Rated
0,10
Intermediate
0,10
Intermediate
0,10
Intermediate
0,10
Idle
---
0,15
3.7.1.2. Specification B.
For engines covered by Section 1A(ii) of Annex I, the following 5-mode cycle 1 shall be followed in
dynamometer operation on the test engine
Mode Number
Engine Speed
Load
Weighting Factor
Rated
0,05
Rated
0,25
Rated
0,30
Rated
0,30
Rated
0,10
The load figures are percentage values of the torque corresponding to the prime power rating defined
as the maximum power available during a variable power sequence, which may be run for an
unlimited number of hours per year, between stated maintenance intervals and under the stated
ambient conditions, the maintenance being carried out as prescribed by the manufacturer.
3.7.1.3 Specification C.
For propulsion engines 1 intended to be used in inland waterway vessels the ISO test procedure as
specified by ISO 81784:2002(E) and IMO MARPOL 73/78, Annex VI (NO x Code) shall be used.
Propulsion engines that operate on a fixed-pitch propeller curve shall be tested on a dynamometer
using the following 4-mode steady-state cycle 2 developed to represent in-use operation of
commercial marine diesel engines
Mode Number
Engine Speed Load
Weighting
Factor
100%
0,20
(Rated)
91%
0,50
80%
0,15
63%
0,15
Fixed speed inland waterway propulsion engines with variable pitch or electrically coupled propellers
shall be tested on a dynamometer using the following 4-mode steady-state cycle 3 characterised by the
same load and weighting factors as the above cycle, but with engine operated in each mode at rated
speed
Note 1 shall be amended as follows: Identical with C1 cycle as described in Paragraph 8.3.1.1 of the ISO8178-4: 2002(E)
Note 2 shall be amended as follows: Identical with D2 cycle as described in Paragraph 8.4.1 of the ISO8178-4: 2002(E) standard.
Mode Number
Engine
Load
Weighting
Speed
Factor
Rated
0,20
Rated
0,50
Rated
0,15
Rated
0,15
Constant-speed auxiliary engines must be certified to the
ISO D2 duty cycle, i.e. the 5-mode steady-state cycle
specified in Section 3.7.1.2., while variable-speed
auxiliary engines must be certified to the ISO C1 duty
cycle, i.e. the 8-mode steady-state cycle specified in
Section 3.7.1.1.
Identical with E3 cycle as described in Sections 8.5.1,
8.5.2 and 8.5.3 of the ISO8178-4: 2002(E) standard. The
four modes lie on an average propeller curve based on
in-use measurements.
Identical with E2 cycle as described in Sections8.5.1,
8.5.2 and 8.5.3 of the ISO8178-4: 2002(E) standard.
3.7.1.4. Specification D
For engines covered by Section 1A(v) of Annex I, the following 3-mode cycle 1 shall be followed in
dynamometer operation on the test engine
Mode Number
Engine Speed
Load
Weighting
Factor
Rated
0,25
Intermediate
0,15
Idle
-
0,60
Identical with F cycle of ISO 8178-4: 2002 (E) standard."
(g)
Current section 3.7.3. shall be replaced by the following
"The test sequence shall be started. The test shall be performed in the order of the mode numbers as set out above for
the test cycles.
During each mode of the given test cycle after the initial transition period, the specified speed shall be held to within
± 1% of rated speed or ± 3 min-1, whichever is greater, except for low idle which shall be within the tolerances
declared by the manufacturer. The specified torque shall be held so that the average over the period during which the
measurements are being taken is within ± 2% of the maximum torque at the test speed.
For each measuring point a minimum time of 10 minutes is necessary. If for the testing of an engine, longer sampling
times are required for reasons of obtaining sufficient particulate mass on the measuring filter the test mode period can
be extended as necessary.
The mode length shall be recorded and reported.
The gaseous exhaust emission concentration values shall be measured and recorded during the last three minutes of
the mode.
The particulate sampling and the gaseous emission measurement should not commence before engine stabilisation, as
defined by the manufacturer, has been achieved and their completion must be coincident.
The fuel temperature shall be measured at the inlet to the fuel injection pump or as specified by the manufacturer, and
the location of measurement recorded."
(h)
The current section 3.7 shall be renumbered 3.8.
The following section shall be inserted
TEST RUN (NRTC TEST)
Introduction
The non-road transient cycle (NRTC) is listed in Annex III, Appendix 4 as a second-by-second sequence of
normalized speed and torque values applicable to all diesel engines covered by this Directive. In order to perform the
test on an engine test cell, the normalised values shall be converted to the actual values for the individual engine
under test, based on the engine mapping curve. This conversion is referred to as denormalisation, and the test cycle
developed is referred to as the reference cycle of the engine to be tested. With these reference speed and torque
values, the cycle shall be run on the test cell, and the feedback speed and torque values recorded. In order to validate
the test run, a regression analysis between reference and feedback speed and torque values shall be conducted upon
completion of the test.
4.1.1. The use of defeat devices or irrational control or irrational emission control strategies shall be prohibited
Engine mapping procedure
When generating the NRTC on the test cell, the engine shall be mapped before running the test cycle to determine the
speed vs torque curve.
4.2.1.
Determination of the mapping speed range
The minimum and maximum mapping speeds are defined as follows
Minimum mapping speed =
idle speed
n hi x 1,02 or speed where full load torque drops off to zero, whichever is lower
Maximum mapping speed =
(where n hi is the high speed, defined as the highest engine speed where 70% of the rated power is delivered).
4.2.2.
Engine mapping curve
The engine shall be warmed up at maximum power in order to stabilise the engine parameters according to the
recommendation of the manufacturer and good engineering practice. When the engine is stabilised, the engine
mapping shall be performed according to the following procedures.
4.2.2.1.
Transient map
(a)
The engine shall be unloaded and operated at idle speed.
(b)
The engine shall be operated at full load setting of the injection pump at minimum mapping speed.
(c)
The engine speed shall be increased at an average rate of 8 ± 1 min-1 /s from minimum to maximum
mapping speed. Engine speed and torque points shall be recorded at a sample rate of at least one
point per second.
4.2.2.2.
Step map
(a)
The engine shall be unloaded and operated at idle speed.
(b)
The engine shall be operated at full load setting of the injection pump at minimum mapping speed.
(c)
While maintaining full load, the minimum mapping speed shall be maintained for at least 15 s, and
the average torque during the last 5 s shall be recorded. The maximum torque curve from minimum
to maximum mapping speed shall be determined in no greater than 100 ± 20 /min speed increments.
Each test point shall be held for at least 15 s, and the average torque during the last 5 s shall be
recorded.
4.2.3. Mapping curve generation
All data points recorded under section 4.2.2 shall be connected using linear interpolation between points. The
resulting torque curve is the mapping curve and shall be used to convert the normalized torque values of the engine
dynamometer schedule of Annex IV into actual torque values for the test cycle, as described in section 4.3.3.
4.2.4. Alternate mapping
If a manufacturer believes that the above mapping techniques are unsafe or unrepresentative for any given engine,
alternate mapping techniques may be used. These alternate techniques must satisfy the intent of the specified
mapping procedures to determine the maximum available torque at all engine speeds achieved during the test cycles.
Deviations from the mapping techniques specified in this section for reasons of safety or representativeness shall be
approved by the parties involved along with the justification for their use. In no case, however, shall the torque curve
be run by descending engine speeds for governed or turbocharged engines.
4.2.5. Replicate tests
An engine need not be mapped before each and every test cycle. An engine must be remapped prior to a test cycle if
–
an unreasonable amount of time has transpired since the last map, as determined by engineering judgement,
or,
–
physical changes or recalibrations have been made to the engine, which may potentially affect engine
performance.
Generation of the reference test cycle
4.3.1. Reference speed
The reference speed (n ref ) corresponds to the 100% normalized speed values specified in the engine dynamometer
schedule of Annex III, Appendix 4. It is obvious that the actual engine cycle resulting from denormalization to the
reference speed largely depends on selection of the proper reference speed. The reference speed shall be determined
by the following definition
n ref = low speed + 0,95 x (high speed – low speed)
(the high speed is the highest engine speed where 70% of the rated power is delivered, while the low speed is the
lowest engine speed where 50% of the rated power is delivered).
4.3.2. Denormalization of engine speed
The speed shall be denormalized using the following equation
%speed " " reference speed $ idle speed #
# idle speed
Actual speed =
4.3.3. Denormalization of engine torque
The torque values in the engine dynamometer schedule of Annex III, Appendix 4 are normalized to the maximum
torque at the respective speed. The torque values of the reference cycle shall be denormalized, using the mapping
curve determined according to Section 4.2.2, as follows
% torque " max. torque
Actual torque =
(5)
for the respective actual speed as determined in Section 4.3.2.
4.3.4. Example of denormalization procedure
As an example, the following test point shall be denormalized
% speed = 43%
% torque = 82%
Given the following values
reference speed =
2200 /min
idle speed = 600 /min
results in
43 " " 2200 - 600 #
$ 600
actual speed =
=
1288 /min
With the maximum torque of 700 Nm observed from the mapping curve at 1288 /min
82 " 700
actual torque =
=
574 Nm
Dynamometer
4.4.1. When using a load cell, the torque signal shall be transferred to the engine axis and the inertia of the dyno shall be
considered. The actual engine torque is the torque read on the load cell plus the moment of inertia of the brake
multiplied by the angular acceleration. The control system has to perform this calculation in real time.
4.4.2. If the engine is tested with an eddy-current dynamometer, it is recommended that the number of points, where the
T sp # 2 " " " n " sp " $ D
difference
is smaller than - 5% of the peak torque, does not exceed 30 (where T sp is the
n " sp
demanded torque,
is the derivative of the engine speed and· Θ D is the rotational inertia of the eddy-current
dynamometer).
Emissions test run
The following flow chart outlines the test sequence.
Engine Preparation, Pre-test Measurements, Performance Checks and Calibrations
"
Generate Engine Map (Maximum Torque Curve)
"
Run one or more Practice Cycles as necessary to check engine/test cell/emissions systems
"
START
"
Run prescribed Preconditioning Cycle for a minimum of 20 minutes to condition engine and particulate system including
tunnel system (partial flow or full flow).
Particulates are collected on a dummy filter.
"
With engine running, set PM system in by-pass mode and change PM filter to stabilized and weighed sampling filter. Ready
all other systems for sampling and data collection.
"
Run Hot Cycle exhaust emissions test within 5 minutes either from engine shut down or from running engine that has been
brought down to idle conditions.
One or more Practice Cycles may be run as necessary to check engine, test cell and emissions systems before the
measurement cycle.
4.5.1. Preparation of the sampling filters
At least one hour before the test, each filter shall be placed in a petri dish, which is protected against dust
contamination and allows air exchange, and placed in a weighing chamber for stabilization. At the end of the
stabilization period, each filter shall be weighed and the weight shall be recorded. The filter shall then be stored in a
closed petri dish or sealed filter holder until needed for testing. The filter shall be used within eight hours of its
removal from the weighing chamber. The tare weight shall be recorded.
4.5.2. Installation of the measuring equipment
The instrumentation and sample probes shall be installed as required. The tailpipe shall be connected to the full flow
dilution system, if used.
4.5.3. Starting and preconditioning the dilution system and the engine
The dilution system and the engine shall be started and warmed up. The sampling system preconditioning shall be
conducted by operating the engine at a condition of rated-speed, 100 percent torque for a minimum of 20 minutes
while simultaneously operating either the Partial flow Sampling System or the Full flow CVS with secondary dilution
system. Dummy particulate matter emissions samples are then collected. Particulate sample filters need not be
stabilized or weighed, and may be discarded. Filter media may be changed during conditioning as long as the total
sampled time through the filters and sampling system exceeds 20 minutes. Flow rates shall be set at the approximate
flow rates selected for transient testing. Torque shall be reduced from 100 percent torque while maintaining the rated
speed condition as necessary so as not to exceed the 191 o C maximum sample zone temperature specifications.
4.5.4. Starting the particulate sampling system
The particulate sampling system shall be started and run on by-pass. The particulate background level of the dilution
air may be determined by sampling the dilution air prior to entrance of the exhaust into the dilution tunnel. It is
preferred that background particulate sample be collected during the transient cycle if another PM sampling system is
available. Otherwise, the PM sampling system used to collect transient cycle PM can be used. If filtered dilution air
is used, one measurement may be done prior to or after the test. If the dilution air is not filtered, measurements
should be carried out prior to the beginning and after the end of the cycle and the values averaged.
4.5.5. Adjustment of the dilution system
The total diluted exhaust gas flow of a full flow dilution system or the diluted exhaust gas flow through a partial flow
dilution system shall be set to eliminate water condensation in the system, and to obtain a filter face temperature
between 315 K (42°C) and 325 K (52°C).
4.5.6. Checking the analyzers
The emission analyzers shall be set at zero and spanned. If sample bags are used, they shall be evacuated.
4.5.7. Engine starting procedure
The stabilized engine shall be started within 5 min after completion of warm-up according to the starting procedure
recommended by the manufacturer in the owner's manual, using either a production starter motor or the
dynamometer. Optionally, the test may start within 5 min of the engine preconditioning phase without shutting the
engine off, when the engine has been brought to an idle condition.
4.5.8. Cycle run
4.5.8.1.Test sequence
The test sequence shall commence when the engine is started from shut down after the preconditioning phase or from
idle conditions when starting directly from the preconditioning phase with the engine running. The test shall be
performed according to the reference cycle as set out in Annex III, Appendix 4. Engine speed and torque command
set points shall be issued at 5 Hz (10 Hz recommended) or greater. The set points shall be calculated by linear
interpolation between the 1 Hz set points of the reference cycle. Feedback engine speed and torque shall be recorded
at least once every second during the test cycle, and the signals may be electronically filtered.
4.5.8.2.Analyzer response
At the start of the engine or test sequence, if the cycle is started directly from preconditioning, the measuring
equipment shall be started, simultaneously
–
start collecting or analyzing dilution air, if a full flow dilution system is used;
–
start collecting or analyzing raw or diluted exhaust gas, depending on the method used;
–
start measuring the amount of diluted exhaust gas and the required temperatures and pressures;
–
start recording the exhaust gas mass flow rate, if raw exhaust gas analysis is used;
–
recording the feedback data of speed and torque of the dynamometer.
If raw exhaust measurement is used, the emission concentrations (HC, CO and NOx) and the exhaust gas mass flow
rate shall be measured continuously and stored with at least 2 Hz on a computer system. All other data may be
recorded with a sample rate of at least 1 Hz. For analogue analyzers the response shall be recorded, and the
calibration data may be applied online or offline during the data evaluation.
If a full flow dilution system is used, HC and NOx shall be measured continuously in the dilution tunnel with a
frequency of at least 2 Hz. The average concentrations shall be determined by integrating the analyzer signals over
the test cycle. The system response time shall be no greater than 20 s, and shall be coordinated with CVS flow
fluctuations and sampling time/test cycle offsets, if necessary. CO and CO 2 shall be determined by integration or by
analyzing the concentrations in the sample bag collected over the cycle. The concentrations of the gaseous pollutants
in the dilution air shall be determined by integration or by collection in the background bag. All other parameters that
need to be measured shall be recorded with a minimum of one measurement per second (1 Hz).
4.5.8.3. Particulate sampling
At the start of the engine or test sequence, if the cycle is started directly from preconditioning, the particulate
sampling system shall be switched from by-pass to collecting particulates.
If a partial flow dilution system is used, the sample pump(s) shall be adjusted so that the flow rate through the
particulate sample probe or transfer tube is maintained proportional to the exhaust mass flow rate.
If a full flow dilution system is used, the sample pump(s) shall be adjusted so that the flow rate through the
particulate sample probe or transfer tube is maintained at a value within ± 5% of the set flow rate. If flow
compensation (i.e., proportional control of sample flow) is used, it must be demonstrated that the ratio of
main tunnel flow to particulate sample flow does not change by more than ± 5% of its set value (except for
the first 10 seconds of sampling).
NOTE
For double dilution operation, sample flow is the net difference between the flow rate through
the sample filters and the secondary dilution airflow rate.
The average temperature and pressure at the gas meter(s) or flow instrumentation inlet shall be recorded. If
the set flow rate cannot be maintained over the complete cycle (within ± 5%) because of high particulate
loading on the filter, the test shall be voided. The test shall be rerun using a lower flow rate and/or a larger
diameter filter.
4.5.8.4. Engine stalling
If the engine stalls anywhere during the test cycle, the engine shall be preconditioned and restarted, and the
test repeated. If a malfunction occurs in any of the required test equipment during the test cycle, the test shall
be voided.
4.5.8.5. Operations after test
At the completion of the test, the measurement of the exhaust gas mass flow rate, the diluted exhaust gas
volume, the gas flow into the collecting bags and the particulate sample pump shall be stopped. For an
integrating analyzer system, sampling shall continue until system response times have elapsed.
The concentrations of the collecting bags, if used, shall be analyzed as soon as possible and in any case not
later than 20 minutes after the end of the test cycle.
After the emission test, a zero gas and the same span gas shall be used for re-checking the analyzers. The test
will be considered acceptable if the difference between the pre-test and post-test results is less than 2% of the
span gas value.
The particulate filters shall be returned to the weighing chamber no later than one hour after completion of the
test. They shall be conditioned in a petri dish, which is protected against dust contamination and allows air
exchange, for at least one hour, and then weighed. The gross weight of the filters shall be recorded.
Verification of the test run
Data Shift
To minimise the biasing effect of the time lag between the feedback and reference cycle values, the entire
engine speed and torque feedback signal sequence may be advanced or delayed in time with respect to the
reference speed and torque sequence. If the feedback signals are shifted, both speed and torque must be
shifted by the same amount in the same direction.
Calculation of the Cycle Work
The actual cycle work Wact (kWh) shall be calculated using each pair of engine feedback speed and torque
values recorded. The actual cycle work Wact is used for comparison to the reference cycle work Wref and
for calculating the brake specific emissions. The same methodology shall be used for integrating both
reference and actual engine power. If values are to be determined between adjacent reference or adjacent
measured values, linear interpolation shall be used.
In integrating the reference and actual cycle work, all negative torque values shall be set equal to zero and
included. If integration is performed at a frequency of less than 5 Hertz, and if, during a given time segment,
the torque value changes from positive to negative or negative to positive, the negative portion shall be
computed and set equal to zero. The positive portion shall be included in the integrated value.
Wact shall be between -15% and + 5% of Wref.
4.6.3.
Validation Statistics of the Test Cycle
Linear regressions of the feedback values on the reference values shall be performed for speed, torque and
power. This shall be done after any feedback data shift has occurred, if this option is selected. The method of
least squares shall be used, with the best fit equation having the form
y = mx + b
where
feedback (actual) value of speed (min -1 ) , torque (N·m), or
y
=
power (kW)
m
=
slope of the regression line
reference value of speed (min -1 ) , torque (N·m), or power (kW)
x
=
b
=
y intercept of the regression line
The standard error of estimate (SE) of y on x and the coefficient of determination (r²) shall be calculated for each regression
line.
It is recommended that this analysis be performed at 1 Hertz. For a test to be considered valid, the criteria of Table 1 must be
met.
Table 1: Regression Line Tolerances
Speed
Torque
Power
max 100 min -1
Standard error of estimate (SE) of Y on X
max 13% of power map
max 8% of power map
maximum engine torque
maximum engine power
Slope of the regression line, m
0,95 to 1,03
0,83 – 1,03
0,89 – 1,03
Coefficient of determination, r²
min 0,9700
min 0,8800
min 0,9100
± 50 min -1
Y intercept of the regression line, b
± 20 N·m or & 2% of max
± 4 kW or & 2% of max
torque, whichever is
power, whichever is greater
greater
For regression purposes only, point deletions are permitted where noted in Table 2 before doing the regression calculation.
However, those points must not be deleted for the calculation of cycle work and emissions. An idle point is defined as a
point having a normalized reference torque of 0% and a normalized reference speed of 0%. Point deletion may be applied to
the whole or to any part of the cycle.
Table 2. Permitted Point Deletions From Regression Analysis
(points to which the point deletion is applied have to be specified)
CONDITION
SPEED AND/OR TORQUE AND/OR POWER
POINTS WHICH MAY BE DELETED WITH
REFERENCE TO THE CONDITIONS LISTED IN
THE LEFT COLUMN
First 24 (±1) s and last 25 s
Speed, torque and power
Wide open throttle, and torque feedback < 95% torque
Torque and/or power
reference
Wide open throttle, and speed feedback < 95% speed
Speed and/or power
reference
Closed throttle, speed feedback > idle speed + 50 min -1 ,
Torque and/or power
and torque feedback > 105% torque reference
Closed throttle, speed feedback % idle speed + 50 min -1 ,
Speed and/or power
and torque feedback = Manufacturer defined/measured
idle torque ± 2% of max torque
Closed throttle and speed feedback > 105% speed
Speed and/or power"
reference
Appendix 1 shall be replaced by the following
"APPENDIX 1
MEASUREMENT AND SAMPLING PROCEDURES
1. MEASUREMENT AND SAMPLING PROCEDURES (NRSC TEST)
Gaseous and particulate components emitted by the engine submitted for testing shall be measured by the methods
described in Annex VI. The methods of Annex VI describe the recommended analytical systems for the gaseous
emissions (Section 1.1) and the recommended particulate dilution and sampling systems (Section 1.2).
Dynamometer specification
An engine dynamometer with adequate characteristics to perform the test cycle described in Annex III, Section 3.7.1
shall be used. The instrumentation for torque and speed measurement shall allow the measurement of the power
within the given limits. Additional calculations may be necessary. The accuracy of the measuring equipment must
be such that the maximum tolerances of the figures given in point 1.3 are not exceeded.
Exhaust gas flow
The exhaust gas flow shall be determined by one of the methods mentioned in sections 1.2.1 to 1.2.4.
1.2.1. Direct measurement method
Direct measurement of the exhaust flow by flow nozzle or equivalent metering system (for detail see ISO
5167:2000).
NOTE
Direct gaseous flow measurement is a difficult task. Precautions must be taken to avoid measurement
errors that will impact emission value errors.
1.2.2. Air and fuel measurement method
Measurement of the airflow and the fuel flow.
Air flow-meters and fuel flow-meters with the accuracy defined in Section 1.3 shall be used.
The calculation of the exhaust gas flow is as follows
G EXHW = G AIRW + G FUEL (for wet exhaust mass)
1.2.3. Carbon balance method
Exhaust mass calculation from fuel consumption and exhaust gas concentrations using the carbon balance method
(Annex III, Appendix 3).
1.2.4. Tracer measurement method
This method involves measurement of the concentration of a tracer gas in the exhaust.
A known amount of an inert gas (e.g. pure helium) shall be injected into the exhaust gas flow as a tracer. The gas is
mixed and diluted by the exhaust gas, but must not react in the exhaust pipe. The concentration of the gas shall then
be measured in the exhaust gas sample.
In order to ensure complete mixing of the tracer gas, the exhaust gas sampling probe shall be located at least 1 m or
30 times the diameter of the exhaust pipe, whichever is larger, downstream of the tracer gas injection point. The
sampling probe may be located closer to the injection point if complete mixing is verified by comparing the tracer gas
concentration with the reference concentration when the tracer gas is injected upstream of the engine.
The tracer gas flow rate shall be set so that the tracer gas concentration at engine idle speed after mixing becomes
lower than the full scale of the trace gas analyzer.
The calculation of the exhaust gas flow is as follows
G T " " EXH
G EXHW $
60 " " conc mix # conc a #
where
G EXHW
=
instantaneous exhaust mass flow (kg/s)
G T
=
tracer gas flow (cm³/min)
conc mix
=
instantaneous concentration of the tracer gas after mixing, (ppm)
$ EXH
=
density of the exhaust gas (kg/m³)
conc a
=
background concentration of the tracer gas in the intake air (ppm)
The background concentration of the tracer gas (conc a ) may be determined by averaging the background concentration
measured immediately before and after the test run.
When the background concentration is less than 1% of the concentration of the tracer gas after mixing (conc mix. ) at
maximum exhaust flow, the background concentration may be neglected.
The total system shall meet the accuracy specifications for the exhaust gas flow and shall be calibrated according to
Appendix 2, Section 1.11.2
1.2.5. Air flow and air to fuel ratio measurement method
This method involves exhaust mass calculation from the air flow and the air to fuel ratio. The calculation of the
instantaneous exhaust gas mass flow is as follows
#
&
G EXHW * G AIRW " $ $ 1 )
'
'
A/F
"
"
%
(
st
A / F st " 14 , 5
with
$
2 " conc CO " 10 " 4 '
%
(
1 +
%
(
'
conc CO " 10 " 4
3,5
"
conc
"
#
+ conc HC " 10 " 4 ( * % 0 , 45 #
CO2
( " conc CO2 * conc CO " 10 " 4
(
%
(
" 4
conc CO " 10
) %
(
1 *
%
3,5 " conc CO2 ( )
&
"
#
6,9078 " conc CO2 * conc CO " 10 " 4 * conc HC " 10 " 4
where A/Fst
=
stoichiometric air/fuel ratio (kg/kg)
"
=
relative air / fuel ratio
conc CO2
=
dry CO 2 concentration (%)
conc CO =
dry CO concentration (ppm)
conc HC =
HC concentration (ppm)
NOTE: The calculation refers to a diesel fuel with a H/C ratio equal to 1.8.
The air flowmeter shall meet the accuracy specifications in Table 3, the CO 2 analyzer used shall meet the
specifications of clause 1.4.1, and the total system shall meet the accuracy specifications for the exhaust gas flow.
Optionally, air to fuel ratio measurement equipment, such as a zirconia type sensor, may be used for the measurement
of the relative air to fuel ratio in accordance with the specifications of clause 1.4.4.
1.2.6. Total dilute exhaust gas flow
When using a full flow dilution system, the total flow of the dilute exhaust (G TOTW ) shall be measured with a PDP or
CFV or SSV (Annex VI, Section 1.2.1.2.) The accuracy shall conform to the provisions of Annex III, Appendix 2,
Section 2.2.
Accuracy
The calibration of all measurement instruments shall be traceable to national or international standards and comply
with the requirements listed in Table 3.
Table 3. Accuracy of Measuring Instruments
Measuring Instrument
Accuracy
& 2% of reading or & 1% of engine's max. value whichever is larger
& 2% of reading or & 1% of engine's max. value whichever is larger
Fuel consumption
& 2% of engine's max. value
& 2% of reading or & 1% of engine's max. value whichever is larger
& 2,5% of reading or & 1,5% of engine's max. value whichever is larger
Temperatures % 600 K
& 2 K absolute
Temperatures > 600 K
& 1% of reading
Exhaust gas pressure
& 0,2 kPa absolute
Intake air depression
& 0,05 kPa absolute
Atmospheric pressure
& 0,1 kPa absolute
& 0,1 kPa absolute
Absolute humidity
& 5% of reading
& 2% of reading
Diluted exhaust gas flow
& 2% of reading
Determination of the gaseous components
General analyser specifications
The analysers shall have a measuring range appropriate for the accuracy required to measure the
concentrations of the exhaust gas components (section 1.4.1.1). It is recommended that the analysers be
operated in such a way that the measured concentration falls between 15% and 100% of full scale.
If the full scale value is 155 ppm (or ppm C) or less or if read-out systems (computers, data loggers) that
provide sufficient accuracy and resolution below 15% of full scale are used, concentrations below 15% of full
scale are also acceptable. In this case, additional calibrations are to be made to ensure the accuracy of the
calibration curves - Annex III, Appendix 2, section 1.5.5.2.
The electromagnetic compatibility (EMC) of the equipment shall be on a level as to minimize additional
errors.
1.4.1.1. Measurement error
The analyzer shall not deviate from the nominal calibration point by more than ± 2% of the reading or ± 0.3%
of full scale, whichever is larger.
NOTE
For the purpose of this standard, accuracy is defined as the deviation of the analyzer reading
from the nominal calibration values using a calibration gas (' true value)
1.4.1.2. Repeatability
The repeatability, defined as 2,5 times the standard deviation of 10 repetitive responses to a given calibration
or span gas, must be no greater than ± 1% of full scale concentration for each range used above 155 ppm (or
ppm C) or ± 2% of each range used below 155 ppm (or ppm C).
1.4.1.3. Noise
The analyser peak-to-peak response to zero and calibration or span gases over any 10-second period shall not
exceed 2% of full scale on all ranges used.
1.4.1.4. Zero drift
The zero drift during a one-hour period shall be less than 2% of full scale on the lowest range used. The zero
response is defined as the mean response, including noise, to a zero gas during a 30-second time interval.
1.4.1.5. Span drift
The span drift during a one-hour period shall be less than 2% of full scale on the lowest range used. Span is
defined as the difference between the span response and the zero response. The span response is defined as
the mean response, including noise, to a span gas during a 30-second time interval.
Gas drying
The optional gas drying device must have a minimal effect on the concentration of the measured gases.
Chemical dryers are not an acceptable method of removing water from the sample.
Analysers
Sections 1.4.3.1 to 1.4.3.5 of this Appendix describe the measurement principles to be used. A detailed
description of the measurement systems is given in Annex VI.
The gases to be measured shall be analysed with the following instruments. For non-linear analysers, the use
of linearizing circuits is permitted.
1.4.3.1. Carbon monoxide (CO) analysis
The carbon monoxide analyser shall be of the non-dispersive infra-red (NDIR) absorption type.
1.4.3.2. Carbon dioxide (CO 2 ) analysis
The carbon dioxide analyser shall be of the non-dispersive infra-red (NDIR) absorption type.
1.4.3.3. Hydrocarbon (HC) analysis
The hydrocarbon analyser shall be of the heated flame ionization detector (HFID) type with detector, valves,
pipework, etc, heated so as to maintain a gas temperature of 463 K (190°C) ± 10 K.
1.4.3.4. Oxides of nitrogen (NOx) analysis
The oxides of nitrogen analyser shall be of the chemiluminescent detector (CLD) or heated chemiluminescent
detector (HCLD) type with a NO 2 /NO converter, if measured on a dry basis. If measured on a wet basis, a
HCLD with converter maintained above 328 K (55°C) shall be used, provided the water quench check
(Annex III, Appendix 2, section 1.9.2.2) is satisfied.
For both CLD and HCLD, the sampling path shall be maintained at a wall temperature of 328 K to 473 K (
55°C to 200°C) up to the converter for dry measurement, and up to the analyzer for wet measurement.
Air to fuel measurement
The air to fuel measurement equipment used to determine the exhaust gas flow as specified in section 1.2.5
shall be a wide range air to fuel ratio sensor or lambda sensor of Zirconia type.
The sensor shall be mounted directly on the exhaust pipe where the exhaust gas temperature is high enough to
eliminate water condensation.
The accuracy of the sensor with incorporated electronics shall be within
& 3% of reading
" < 2
& 5% of reading
2 %
" < 5
& 10% of reading
5 %"
To fulfil the accuracy specified above, the sensor shall be calibrated as specified by the instrument
manufacturer.
Sampling for gaseous emissions
The gaseous emissions sampling probes must be fitted at least 0,5 m or three times the diameter of the
exhaust pipe - whichever is the larger - upstream of the exit of the exhaust gas system as far as applicable and
sufficiently close to the engine as to ensure an exhaust gas temperature of at least 343 K (70°C) at the probe.
In the case of a multi-cylinder engine with a branched exhaust manifold, the inlet of the probe shall be located
sufficiently far downstream so as to ensure that the sample is representative of the average exhaust emissions
from all cylinders. In multi-cylinder engines having distinct groups of manifolds, such as in a 'V'-engine
configuration, it is permissible to acquire a sample from each group individually and calculate an average
exhaust emission. Other methods which have been shown to correlate with the above methods may be used.
For exhaust emissions calculation the total exhaust mass flow of the engine must be used.
If the composition of the exhaust gas is influenced by any exhaust after-treatment system, the exhaust sample
must be taken upstream of this device in the tests of stage I and downstream of this device in the tests of stage
II. When a full flow dilution system is used for the determination of the particulates, the gaseous emissions
may also be determined in the diluted exhaust gas. The sampling probes shall be close to the particulate
sampling probe in the dilution tunnel (Annex VI, section 1.2.1.2, DT and Section 1.2.2, PSP). CO and CO 2
may optionally be determined by sampling into a bag and subsequent measurement of the concentration in the
sampling bag.
Determination of the particulates
The determination of the particulates requires a dilution system. Dilution may be accomplished by a partial
flow dilution system or a full flow dilution system. The flow capacity of the dilution system shall be large
enough to completely eliminate water condensation in the dilution and sampling systems, and maintain the
temperature of the diluted exhaust gas between 315 K (42°C) and 325 K (52°C) immediately upstream of the
filter holders. De-humidifying the dilution air before entering the dilution system is permitted, if the air
humidity is high. Dilution air pre-heating above the temperature limit of 303 K (30 °C) is recommended, if
the ambient temperature is below 293 K (20°C). However, the diluted air temperature must not exceed 325 K
(52°C) prior to the introduction of the exhaust in the dilution tunnel.
NOTE
For steady-state procedure, the filter temperature may be kept at or below the maximum
temperature of 325 K (52°C) instead of respecting the temperature range of 42°C – 52°C.
For a partial flow dilution system, the particulate sampling probe must be fitted close to and upstream of the
gaseous probe as defined in Section 4.4 and in accordance with Annex VI, section 1.2.1.1, figure 4-12 EP and
SP.
The partial flow dilution system has to be designed to split the exhaust stream into two fractions, the smaller
one being diluted with air and subsequently used for particulate measurement. From that it is essential that
the dilution ratio be determined very accurately. Different splitting methods can be applied, whereby the type
of splitting used dictates to a significant degree the sampling hardware and procedures to be used (Annex VI,
section 1.2.1.1).
To determine the mass of the particulates, a particulate sampling system, particulate sampling filters, a
microgram balance and a temperature and humidity controlled weighing chamber are required.
For particulate sampling, two methods may be applied
–
the single filter method uses one pair of filters (1.5.1.3. of this Appendix) for all modes of the test
cycle. Considerable attention must be paid to sampling times and flows during the sampling phase of
the test. However, only one pair of filters will be required for the test cycle,
–
the multiple filter method dictates that one pair of filters (section 1.5.1.3. of this Appendix) is used for
each of the individual modes of the test cycle. This method allows more lenient sample procedures
but uses more filters.
Particulate sampling filters
1.5.1.1. Filter specification
Fluorocarbon coated glass fibre filters or fluorocarbon based membrane filters are required for certification
tests. For special applications different filter materials may be used. All filter types shall have a 0,3 µm DOP
(di-octylphthalate) collection efficiency of at least 99% at a gas face velocity between 35 and 100 cm/s.
When performing correlation tests between laboratories or between a manufacturer and an approval authority,
filters of identical quality must be used.
1.5.1.2. Filter size
Particulate filters must have a minimum diameter of 47 mm (37 mm stain diameter). Larger diameter filters
are acceptable (section 1.5.1.5.).
1.5.1.3. Primary and back-up filters
The diluted exhaust shall be sampled by a pair of filters placed in series (one primary and one back-up filter)
during the test sequence. The back-up filter shall be located no more than 100 mm downstream of, and shall
not be in contact with, the primary filter. The filters may be weighed separately or as a pair with the filters
placed stain side to stain side.
1.5.1.4. Filter face velocity
A gas face velocity through the filter of 35 to 100 cm/s shall be achieved. The pressure drop increase
between the beginning and the end of the test shall be no more than 25 kPa.
1.5.1.5. Filter loading
The recommended minimum filter loadings for the most common filter sizes are shown in the following table.
For larger filter sizes, the minimum filter loading shall be 0,065 mg/1000 mm² filter area.
Filter Diameter
Recommended stain diameter
Recommended minimum
(mm)
(mm)
loading (mg)
0,11
0,25
0,41
0,62
For the multiple filter method, the recommended minimum filter loading for the sum of all filters shall be the
product of the appropriate value above and the square root of the total number of modes.
Weighing chamber and analytical balance specifications
1.5.2.1. Weighing chamber conditions
The temperature of the chamber (or room) in which the particulate filters are conditioned and weighed shall
be maintained to within 295 K (22°C) ± 3 K during all filter conditioning and weighing. The humidity shall
be maintained to a dew point of 282,5 (9,5°C) ± 3 K and a relative humidity of 45 ± 8%.
1.5.2.2. Reference filter weighing
The chamber (or room) environment shall be free of any ambient contaminants (such as dust) that would
settle on the particulate filters during their stabilisation. Disturbances to weighing room specifications as
outlined in section 1.5.2.1 will be allowed if the duration of the disturbances does not exceed 30 minutes.
The weighing room should meet the required specifications prior to personnel entrance into the weighing
room. At least two unused reference filters or reference filter pairs shall be weighed within four hours of, but
preferably at the same time as the sample filter (pair) weighing. They shall be the same size and material as
the sample filters.
If the average weight of the reference filters (reference filter pairs) changes between sample filter weighing
by more than 10#g, then all sample filters shall be discarded and the emissions test repeated.
If the weighing room stability criteria outlined in section 1.5.2.1 is not met, but the reference filter (pair)
weighing meet the above criteria, the engine manufacturer has the option of accepting the sample filter
weights or voiding the tests, fixing the weighing room control system and re-running the test.
1.5.2.3. Analytical balance
The analytical balance used to determine the weights of all filters shall have a precision (standard deviation)
of 2 µg and a resolution of 1 µg (1 digit = 1 µg) specified by the balance manufacturer.
1.5.2.4. Elimination of static electricity effects
To eliminate the effects of static electricity, the filters shall be neutralized prior to weighing, for example, by
a Polonium neutralizer or a device of similar effect.
Additional specifications for particulate measurement
All parts of the dilution system and the sampling system from the exhaust pipe up to the filter holder, which
are in contact with raw and diluted exhaust gas, must be designed to minimize deposition or alteration of the
particulates. All parts must be made of electrically conductive materials that do not react with exhaust gas
components, and must be electrically grounded to prevent electrostatic effects.
2. MEASUREMENT AND SAMPLING PROCEDURES (NRTC TEST)
Introduction
Gaseous and particulate components emitted by the engine submitted for testing shall be measured by the methods of
Annex VI. The methods of Annex VI describe the recommended analytical systems for the gaseous emissions
(Section 1.1) and the recommended particulate dilution and sampling systems (Section 1.2).
Dynamometer and test cell equipment
The following equipment shall be used for emission tests of engines on engine dynamometers
Engine Dynamometer
An engine dynamometer shall be used with adequate characteristics to perform the test cycle described in Appendix 4
to this Annex. The instrumentation for torque and speed measurement shall allow the measurement of the power
within the given limits. Additional calculations may be necessary. The accuracy of the measuring equipment must be
such that the maximum tolerances of the figures given in Table 3 are not exceeded.
Other Instruments
Measuring instruments for fuel consumption, air consumption, temperature of coolant and lubricant, exhaust gas
pressure and intake manifold depression, exhaust gas temperature, air intake temperature, atmospheric pressure,
humidity and fuel temperature shall be used, as required. These instruments shall satisfy the requirements given in
Table 3
Table 3. Accuracy of Measuring Instruments
Measuring Instrument
Accuracy
Engine speed
& 2% of reading or & 1% of engine's max. value, whichever is larger
& 2% of reading or & 1% of engine's max. value, whichever is larger
Fuel consumption
& 2% of engine's max. value
Air consumption
& 2% of reading or & 1% of engine's max. value, whichever is larger
Exhaust gas flow
& 2,5% of reading or & 1,5% of engine's max. value, whichever is larger
Temperatures % 600 K
& 2 K absolute
Temperatures > 600 K
& 1% of reading
Exhaust gas pressure
& 0,2 kPa absolute
Intake air depression
& 0,05 kPa absolute
Atmospheric pressure
& 0,1 kPa absolute
Other pressures
& 0,1 kPa absolute
Absolute humidity
& 5% of reading
Dilution air flow
& 2% of reading
Diluted exhaust gas flow
& 2% of reading
Raw Exhaust Gas Flow
For calculating the emissions in the raw exhaust gas and for controlling a partial flow dilution system, it is necessary
to know the exhaust gas mass flow rate. For determinating the exhaust mass flow rate, either of the methods
described below may be used.
For the purpose of emissions calculation, the response time of either method described below shall be equal to or less
than the requirement for the analyzer response time, as defined in Appendix 2, Section 1.11.1.
For the purpose of controlling a partial flow dilution system, a faster response is required. For partial flow dilution
systems with online control, a response time of % 0,3 s is required. For partial flow dilution systems with look ahead
control based on a pre-recorded test run, a response time of the exhaust flow measurement system of % 5 s with a rise
time of % 1 s is required. The system response time shall be specified by the instrument manufacturer. The combined
response time requirements for exhaust gas flow and partial flow dilution system are indicated in Section 2.4.
Direct measurement method
Direct measurement of the instantaneous exhaust flow may be done by systems, such as
–
pressure differential devices, like flow nozzle, (for details see ISO 5167: 2000)
–
ultrasonic flowmeter
–
vortex flowmeter.
Precautions shall be taken to avoid measurement errors, which will impact emission value errors. Such precautions
include the careful installation of the device in the engine exhaust system according to the instrument manufacturers'
recommendations and to good engineering practice. Especially, engine performance and emissions must not be
affected by the installation of the device.
The flowmeters shall meet the accuracy specifications of Table 3.
Air and fuel measurement method
This involves measurement of the airflow and the fuel flow with suitable flowmeters. The calculation of the
instantaneous exhaust gas flow is as follows
G EXHW =
G AIRW + G FUEL (for wet exhaust mass)
The flowmeters shall meet the accuracy specifications of Table 3, but shall also be accurate enough to also meet the
accuracy specifications for the exhaust gas flow.
Tracer measurement method
This involves measurement of the concentration of a tracer gas in the exhaust.
A known amount of an inert gas (e.g. pure helium) shall be injected into the exhaust gas flow as a tracer. The gas is
mixed and diluted by the exhaust gas, but must not react in the exhaust pipe. The concentration of the gas shall then
be measured in the exhaust gas sample.
In order to ensure complete mixing of the tracer gas, the exhaust gas sampling probe shall be located at least 1 m or
30 times the diameter of the exhaust pipe, whichever is larger, downstream of the tracer gas injection point. The
sampling probe may be located closer to the injection point if complete mixing is verified by comparing the tracer gas
concentration with the reference concentration when the tracer gas is injected upstream of the engine.
The tracer gas flow rate shall be set so that the tracer gas concentration at engine idle speed after mixing becomes
lower than the full scale of the trace gas analyzer.
The calculation of the exhaust gas flow is as follows
G T " " EXH
G EXHW $
60 " " conc mix # conc a #
where
G EXHW =
instantaneous exhaust mass flow (kg/s)
G T
=
tracer gas flow (cm³/min)
conc mix =
instantaneous concentration of the tracer gas after mixing (ppm)
" EXH
=
density of the exhaust gas (kg/m³)
conc a
=
background concentration of the tracer gas in the intake air (ppm)
The background concentration of the tracer gas (conc a ) may be determined by averaging the background
concentration measured immediately before the test run and after the test run.
When the background concentration is less than 1% of the concentration of the tracer gas after mixing (conc mix. ) at
maximum exhaust flow, the background concentration may be neglected.
The total system shall meet the accuracy specifications for the exhaust gas flow, and shall be calibrated according to
Appendix 2, paragraph 1.11.2
Air flow and air to fuel ratio measurement method
This involves exhaust mass calculation from the airflow and the air to fuel ratio. The calculation of the instantaneous
exhaust gas mass flow is as follows
#
&
G EXHW * G AIRW " $ $ 1 )
'
A/F st " " ' (
%
A / F st " 14 , 5
with
$
2 " conc CO " 10 " 4 '
%
(
+
%
(
'
conc CO " 10 " 4
3,5
"
conc
"
#
+ conc HC " 10 " 4 ( * % 0 , 45 #
CO2
( " conc CO2 * conc CO " 10 " 4
(
) % %
(
"
conc CO " 10
(
1 *
%
3,5 " conc CO2 ( )
&
"
#
6,9078 " conc CO2 * conc CO " 10 " 4 * conc HC " 10 " 4
where
A/Fst =
stoichiometric air/fuel ratio (kg/kg)
"
=
relative air / fuel ratio
conc CO2
=
dry CO2 concentration (%)
conc CO =
dry CO concentration (ppm)
conc HC =
HC concentration (ppm)
NOTE: The calculation refers to a diesel fuel with a H/C ratio equal to 1.8.
The air flowmeter shall meet the accuracy specifications in Table 3, the CO 2 analyzer used shall meet the
specifications of section 2.3.1, and the total system shall meet the accuracy specifications for the exhaust gas flow.
Optionally, air to fuel ratio measurement equipment, such as a zirconia type sensor, may be used for the measurement
of the excess air ratio in accordance with the specifications of section 2.3.4.
Diluted Exhaust Gas Flow
For calculation of the emissions in the diluted exhaust gas, it is necessary to know the diluted exhaust gas mass flow
rate. The total diluted exhaust gas flow over the cycle (kg/test) shall be calculated from the measurement values over
the cycle and the corresponding calibration data of the flow measurement device (V 0 for PDP, K V for CFV, C d for
SSV): the corresponding methods described in Appendix 3, section 2.2.1 shall be used. If the total sample mass of
particulates and gaseous pollutants exceeds 0,5% of the total CVS flow, the CVS flow shall be corrected or the
particulate sample flow shall be returned to the CVS prior to the flow measuring device.
Determination of the gaseous components
General Analyser Specifications
The analysers shall have a measuring range appropriate for the accuracy required to measure the concentrations of the
exhaust gas components (section 1.4.1.1). It is recommended that the analysers be operated in such a way that the
measured concentration falls between 15% and 100% of full scale.
If the full scale value is 155 ppm (or ppm C) or less, or if read-out systems (computers, data loggers) that provide
sufficient accuracy and resolution below 15% of full scale are used, concentrations below 15% of full scale are also
acceptable. In this case, additional calibrations are to be made to ensure the accuracy of the calibration curves -
Annex III, Appendix 2, section 1.5.5.2.
The electromagnetic compatibility (EMC) of the equipment shall be of a level such as to minimize additional errors.
2.3.1.1. Measurement error
The analyzer shall not deviate from the nominal calibration point by more than ± 2% of the reading or ± 0,3% of full
scale, whichever is larger.
NOTE
For the purpose of this standard, accuracy is defined as the deviation of the analyzer reading from the
nominal calibration values using a calibration gas (' true value).
2.3.1.2. Repeatability
The repeatability, defined as 2,5 times the standard deviation of 10 repetitive responses to a given calibration or span
gas, must be no greater than ± 1% of full scale concentration for each range used above 155 ppm (or ppm C) or ± 2%
for each range used below 155 ppm (or ppm C).
2.3.1.3. Noise
The analyser peak-to-peak response to zero and calibration or span gases over any 10-second period shall not exceed
2% of full scale on all ranges used.
2.3.1.4. Zero drift
The zero drift during a one-hour period shall be less than 2% of full scale on the lowest range used. The zero
response is defined as the mean response, including noise, to a zero gas during a 30-second time interval.
2.3.1.5. Span drift
The span drift during a one-hour period shall be less than 2% of full scale on the lowest range used. Span is defined
as the difference between the span response and the zero response. The span response is defined as the mean
response, including noise, to a span gas during a 30-second time interval.
2.3.1.6. Rise Time
For raw exhaust gas analysis, the rise time of the analyzer installed in the measurement system shall not exceed 2,5 s.
NOTE
Only evaluating the response time of the analyzer alone will not clearly define the suitability of the
total system for transient testing. Volumes, and especially dead volumes, through out the system will
not only affect the transportation time from the probe to the analyzer, but also affect the rise time.
Also transport times inside of an analyzer would be defined as analyzer response time, like the
converter or water traps inside of a NOx analyzers. The determination of the total system response
time is described in Appendix 2, Section 1.11.1.
Gas Drying
Same specifications as for NRSC test cycle apply (Section 1.4.2) as described here below.
The optional gas drying device must have a minimal effect on the concentration of the measured gases. Chemical
dryers are not an acceptable method of removing water from the sample.
Analysers
Same specifications as for NRSC test cycle apply (Section 1.4.3) as described here below.
The gases to be measured shall be analysed with the following instruments. For non-linear analysers, the use of
linearizing circuits is permitted.
2.3.3.1. Carbon monoxide (CO) analysis
The carbon monoxide analyser shall be of the non-dispersive infra-red (NDIR) absorption type.
2.3.3.2. Carbon dioxide (CO 2 ) analysis
The carbon dioxide analyser shall be of the non-dispersive infra-red (NDIR) absorption type.
2.3.3.3. Hydrocarbon (HC) analysis
The hydrocarbon analyser shall be of the heated flame ionization detector (HFID) type with detector, valves,
pipework, etc, heated so as to maintain a gas temperature of 463 K (190°C) ± 10 K.
2.3.3.4. Oxides of nitrogen (NOx) analysis
The oxides of nitrogen analyser shall be of the chemiluminescent detector (CLD) or heated chemiluminescent
detector (HCLD) type with a NO 2 /NO converter, if measured on a dry basis. If measured on a wet basis, a HCLD
with converter maintained above 328 K (55°C shall be used, provided the water quench check (Annex III, Appendix
2, section 1.9.2.2) is satisfied.
For both CLD and HCLD, the sampling path shall be maintained at a wall temperature of 328 K to 473 K ( 55°C to
200°C) up to the converter for dry measurement, and up to the analyzer for wet measurement.
Air to fuel measurement
The air to fuel measurement equipment used to determine the exhaust gas flow as specified in section 2.2.3 shall be a
wide range air to fuel ratio sensor or lambda sensor of Zirconia type.
The sensor shall be mounted directly on the exhaust pipe where the exhaust gas temperature is high enough to
eliminate water condensation.
The accuracy of the sensor with incorporated electronics shall be within
& 3% of reading
" < 2
& 5% of reading
2 %
" < 5
& 10% of reading 5 % "
To fulfil the accuracy specified above, the sensor shall be calibrated as specified by the instrument manufacturer.
Sampling of Gaseous Emissions
2.3.5.1. Raw exhaust gas flow
For calculation of the emissions in the raw exhaust gas the same specifications as for NRSC test cycle apply (Section
1.4.4), as described here below.
The gaseous emissions sampling probes must be fitted at least 0,5 m or three times the diameter of the exhaust pipe –
whichever is the larger – upstream of the exit of the exhaust gas system as far as applicable and sufficiently close to
the engine as to ensure an exhaust gas temperature of at least 343 K (70°C) at the probe.
In the case of a multicylinder engine with a branched exhaust manifold, the inlet of the probe shall be located
sufficiently far downstream so as to ensure that the sample is representative of the average exhaust emissions from all
cylinders. In multicylinder engines having distinct groups of manifolds, such as in a 'V'-engine configuration, it is
permissible to acquire a sample from each group individually and calculate an average exhaust emission. Other
methods which have been shown to correlate with the above methods may be used. For exhaust emissions
calculation the total exhaust mass flow of the engine must be used.
If the composition of the exhaust gas is influenced by any exhaust after-treatment system, the exhaust sample must be
taken upstream of this device in the tests of stage I and downstream of this device in the tests of stage II.
2.3.5.2. Diluted exhaust gas flow
If a full flow dilution system is used, the following specifications apply.
The exhaust pipe between the engine and the full flow dilution system shall conform to the requirements of Annex
VI.
The gaseous emissions sample probe(s) shall be installed in the dilution tunnel at a point where the dilution air and
exhaust gas are well mixed, and in close proximity to the particulates sampling probe.
Sampling can generally be done in two ways
–
the pollutants are sampled into a sampling bag over the cycle and measured after completion of the test;
–
the pollutants are sampled continuously and integrated over the cycle; this method is mandatory for HC and
NO x .
The background concentrations shall be sampled upstream of the dilution tunnel into a sampling bag, and shall be
subtracted from the emissions concentration according to Appendix 3, Section 2.2.3.
Determination of the particulates
Determination of the particulates requires a dilution system. Dilution may be accomplished by a partial flow dilution
system or a full flow dilution system. The flow capacity of the dilution system shall be large enough to completely
eliminate water condensation in the dilution and sampling systems, and maintain the temperature of the diluted
exhaust gas between 315 K (42°C) and 325 K (52°C) immediately upstream of the filter holders. De-humidifying the
dilution air before entering the dilution system is permitted, if the air humidity is high. Dilution air pre-heating above
the temperature limit of 303 K (30 °C) is recommended if the ambient temperature is below 293 K (20 C). However,
the diluted air temperature must not exceed 325 K (52°C) prior to the introduction of the exhaust in the dilution
tunnel.
The particulate sampling probe shall be installed in close proximity to the gaseous emissions sampling probe, and the
installation shall comply with the provisions of Section 2.3.5.
To determine the mass of the particulates, a particulate sampling system, particulate sampling filters, microgram
balance, and a temperature and humidity controlled weighing chamber, are required.
Partial flow dilution system specifications
The partial flow dilution system has to be designed to split the exhaust stream into two fractions, the smaller one
being diluted with air and subsequently used for particulate measurement. For this it is essential that the dilution ratio
be determined very accurately. Different splitting methods can be applied, whereby the type of splitting used dictates
to a significant degree the sampling hardware and procedures to be used (Annex VI, section 1.2.1.1).
For the control of a partial flow dilution system, a fast system response is required. The transformation time for the
system shall be determined by the procedure described in Appendix 2, Section 1.11.1.
If the combined transformation time of the exhaust flow measurement (see previous Section) and the partial flow
system is less than 0,3 s, online control may be used. If the transformation time exceeds 0,3 s, look ahead control
based on a pre-recorded test run must be used. In this case, the rise time shall be % 1 s and the delay time of the
combination % 10 s.
The total system response shall be designed as to ensure a representative sample of the particulates, G SE , proportional
to the exhaust mass flow. To determine the proportionality, a regression analysis of G SE versus G EXHW shall be
conducted on a minimum 5 Hz data acquisition rate, and the following criteria shall be met
The correlation coefficient r 2 of the linear regression between G SE and G EXHW shall be not less than 0,95.
–
–
The standard error of estimate of G SE on G EXHW shall not exceed 5% of G SE maximum.
–
G SE intercept of the regression line shall not exceed & 2% of G SE maximum.
Optionally, a pre-test may be run, and the exhaust mass flow signal of the pre-test be used for controlling the sample
flow into the particulate system ("look-ahead control"). Such a procedure is required if the transformation time of the
particulate system, t 50,P or/and the transformation time of the exhaust mass flow signal, t 50,F are > 0,3 s. A correct
control of the partial dilution system is obtained, if the time trace of G EXHW,pre of the pre-test, which controls G SE , is
shifted by a "look-ahead" time of t 50,P + t 50,F .
For establishing the correlation between G SE and G EXHW the data taken during the actual test shall be used, with G EXHW
time aligned by t 50,F relative to G SE (no contribution from t 50,P to the time alignment). That is, the time shift between
G EXHW and G SE is the difference in their transformation times that were determined in Appendix 2, Section 2.6.
For partial flow dilution systems, the accuracy of the sample flow G SE is of special concern, if not measured directly,
but determined by differential flow measurement
G SE = G TOTW – G DILW
In this case an accuracy of & 2% for G TOTW and G DILW is not sufficient to guarantee acceptable accuracies of G SE. If
the gas flow is determined by differential flow measurement, the maximum error of the difference shall be such that
the accuracy of G SE is within & 5% when the dilution ratio is less than 15. It can be calculated by taking root-mean-
square of the errors of each instrument.
Acceptable accuracies of G SE can be obtained by either of the following methods
(a)
The absolute accuracies of G TOTW and G DILW are & 0,2% which guarantees an accuracy of G SE of % 5% at a
dilution ratio of 15. However, greater errors will occur at higher dilution ratios.
(b)
Calibration of G DILW relative to G TOTW is carried out such that the same accuracies for G SE as in (a) are
obtained. For the details of such a calibration see Appendix 2, Section 2.6.
(c)
The accuracy of G SE is determined indirectly from the accuracy of the dilution ratio as determined by a tracer
gas, e.g. CO 2 . Again, accuracies equivalent to method (a) for G SE are required.
(d)
The absolute accuracy of G TOTW and G DILW is within & 2% of full scale, the maximum error of the difference
between G TOTW and G DILW is within 0,2%, and the linearity error is within & 0.2% of the highest G TOTW
observed during the test.
Particulate Sampling Filters
2.4.1.1. Filter specification
Fluorocarbon coated glass fibre filters or fluorocarbon based membrane filters are required for certification tests. For
special applications different filter materials may be used. All filter types shall have a 0,3 µm DOP (di-
octylphthalate) collection efficiency of at least 99% at a gas face velocity between 35 and 100 cm/s. When
performing correlation tests between laboratories or between a manufacturer and an approval authority, filters of
identical quality must be used.
2.4.1.2. Filter size
Particulate filters must have a minimum diameter of 47 mm (37 mm stain diameter). Larger diameter filters are
acceptable (section 2.4.1.5.).
2.4.1.3. Primary and back-up filters
The diluted exhaust shall be sampled by a pair of filters placed in series (one primary and one back-up filter) during
the test sequence. The back-up filter shall be located no more than 100 mm downstream of, and shall not be in
contact with, the primary filter. The filters may be weighed separately or as a pair with the filters placed stain side to
stain side.
2.4.1.4. Filter face velocity
A gas face velocity through the filter of 35 to 100 cm/s shall be achieved. The pressure drop increase between the
beginning and the end of the test shall be no more than 25 kPa.
2.4.1.5. Filter loading
The recommended minimum filter loadings for the most common filter sizes are shown in the following table. For
larger filter sizes, the minimum filter loading shall be 0,065 mg/1000 mm² filter area.
Filter Diameter
Recommended stain diameter (mm)
Recommended minimum loading
(mm)
(mg)
0,11
0,25
0,41
0,62
Weighing Chamber and Analytical Balance Specifications
2.4.2.1. Weighing chamber conditions
The temperature of the chamber (or room) in which the particulate filters are conditioned and weighed shall be
maintained to within 295 K (22°C) ± 3 K during all filter conditioning and weighing. The humidity shall be
maintained to a dewpoint of 282,5 (9,5°C) ± 3 K and a relative humidity of 45 ± 8%.
2.4.2.2. Reference filter weighing
The chamber (or room) environment shall be free of any ambient contaminants (such as dust) that would settle on the
particulate filters during their stabilisation. Disturbances to weighing room specifications as outlined in section
2.4.2.1 will be allowed if the duration of the disturbances does not exceed 30 minutes. The weighing room should
meet the required specifications prior to personnel entrance into the weighing room. At least two unused reference
filters or reference filter pairs shall be weighed within four hours of, but preferably at the same time as the sample
filter (pair) weighing. They shall be the same size and material as the sample filters.
If the average weight of the reference filters (reference filter pairs) changes between sample filter weighing by more
than 10#g, then all sample filters shall be discarded and the emissions test repeated.
If the weighing room stability criteria outlined in section 2.4.2.1 are not met, but the reference filter (pair) weighing
meet the above criteria, the engine manufacturer has the option of accepting the sample filter weights or voiding the
tests, fixing the weighing room control system and re-running the test.
2.4.2.3. Analytical balance
The analytical balance used to determine the weights of all filters shall have a precision (standard deviation) of 2 µg
and a resolution of 1 µg (1 digit = 1 µg) specified by the balance manufacturer.
2.4.2.4. Elimination of static electricity effects
To eliminate the effects of static electricity, the filters shall be neutralized prior to weighing, for example, by a
Polonium neutralizer or a device having similar effect.
Additional Specifications for Particulate Measurement
All parts of the dilution system and the sampling system from the exhaust pipe up to the filter holder, which are in
contact with raw and diluted exhaust gas, must be designed to minimize deposition or alteration of the particulates.
All parts must be made of electrically conductive materials that do not react with exhaust gas components, and must
be electrically grounded to prevent electrostatic effects."
Appendix 2 shall be amended as follows
(a)
The title shall be amended as follows
"APPENDIX 2
CALIBRATION PROCEDURE (NRSC, NRTC 1 )"
(b)
Section 1.2.2 shall be amended as follows
After the current text the following shall be added
"This accuracy implies that primary gases used for blending shall be known to have an accuracy of at least & 1%,
traceable to national or international gas standards. The verification shall be performed at between 15 and 50% of
full scale for each calibration incorporating a blending device. An additional verification may be performed using
another calibration gas, if the first verification has failed.
Optionally, the blending device may be checked with an instrument which by nature is linear, e.g. using NO gas with
a CLD. The span value of the instrument shall be adjusted with the span gas directly connected to the instrument.
The blending device shall be checked at the used settings and the nominal value shall be compared to the measured
concentration of the instrument. This difference shall in each point be within ± 1% of the nominal value.
Other methods may be used based on good engineering practice and with the prior agreement of the parties involved.
NOTE
A precision gas divider of accuracy is within & 1%, is recommended for establishing the accurate
analyzer calibration curve. The gas divider shall be calibrated by the instrument manufacturer."
(c)
section 1.5.5.1 shall be amended as follows
(i)
the first sentence shall be replaced by the following
"The analyser calibration curve is established by at least six calibration points (excluding zero) spaced as
uniformly as possible".
(ii)
the third indent shall be replaced by the following
"The calibration curve must not differ by more than ± 2% from the nominal value of each calibration point
and by more than ±0,3% of full scale at zero."
(d)
in section1.5.5.2, the last indent shall be replaced by the following
"The calibration curve must not differ by more than ± 4% from the nominal value of each calibration point and by
more than ± 0,3% of full scale at zero."
(e)
the text under section 1.8.3 shall be replaced by the following
The calibration procedure is common for both NRSC and NRTC tests, with the exception of the requirements specified in Sections 1.11 and
"The oxygen interference check shall be determined when introducing an analyser into service and after major service
A range shall be chosen where the oxygen interference check gases will fall within the upper 50%. The test shall be
conducted with the oven temperature set as required.
1.8.3.1. Oxygen interference gases
Oxygen interference check gases shall contain propane with 350 ppmC ÷ 75 ppmC hydrocarbon. The
concentration value shall be determined to calibration gas tolerances by chromatographic analysis of
total hydrocarbons plus impurities or by dynamic blending. Nitrogen shall be the predominant diluent
with the balance oxygen. Blends required for Diesel engine testing are
O 2 concentration
Balance
21 (20 to 22)
Nitrogen
10 (9 to 11
Nitrogen
5 (4 to 6)
Nitrogen
(a)
The analyzer shall be zeroed.
(b)
The analyzer shall be spanned with the 21% oxygen blend.
(c)
The zero response shall be rechecked. If it has changed more than 0,5% of full scale clauses (a) and
(b) shall be repeated.
(d)
The 5% and 10% oxygen interference check gases shall be introduced.
(e)
The zero response shall be rechecked. If it has changed more than ± 1% of full scale, the test shall be
repeated.
(f)
The oxygen interference (%O 2 I) shall be calculated for each mixture in (d) as follows
" B # C # " 100
O 2 I $
B
A =
hydrocarbon concentration (ppmC) of the span gas used in (b)
B =
hydrocarbon concentration (ppmC) of the oxygen interference check gases used in (d)
C =
analyzer response
" ppmC # " A
D
D =
percent of full scale analyzer response due to A.
(g)
The % of oxygen interference (%O 2 I) shall be less than ± 3,0% for all required oxygen interference
check gases prior to testing.
(h)
If the oxygen interference is greater than ± 3,0%, the air flow above and below the manufacturer's
specifications shall be incrementally adjusted, repeating clause 1.8.1 for each flow.
(i)
If the oxygen interference is greater than ± 3,0% after adjusting the air flow, the fuel flow and
thereafter the sample flow shall be varied, repeating clause 1.8.1 for each new setting.
(j)
If the oxygen interference is still greater than ± 3,0%, the analyzer, FID fuel, or burner air shall be
repaired or replaced prior to testing. This clause shall then be repeated with the repaired or replaced
equipment or gases."
(f)
Current paragraph 1.9.2.2 shall be amended as follows
(i)
the first subparagraph shall be replaced by the following
"This check applies to wet gas concentration measurements only. Calculation of water quench must consider
dilution of the NO span gas with water vapour and scaling of water vapour concentration of the mixture to
that expected during testing. A NO span gas having a concentration of 80 to 100% of full scale to the normal
operating range shall be passed through the (H)CLD and the NO value recorded as D. The NO gas shall be
bubbled through water at room temperature and passed through the (H)CLD and NO value recorded as C.
The water temperature shall be determined and recorded as F. The mixture's saturation vapour pressure that
corresponds to the bubbler water temperature (F) shall be determined and recorded as G. The water vapour
concentration (in %) of the mixture shall be calculated as follows:"
(ii)
The third subparagraph shall be replaced by the following
"and recorded as De. For diesel exhaust, the maximum exhaust water vapour concentration (in %)
expected during testing shall be estimated, under the assumption of a fuel atom H/C ratio of 1,8 to 1,
from the maximum CO 2 concentration in the exhaust gas or from the undiluted CO 2 span gas
concentration (A, as measured in section 1.9.2.1) as follows
(g)
the following section shall be inserted
Additional calibration requirements for raw exhaust measurements over
NRTC test
1.11.1. Response time check of the analytical system
The system settings for the response time evaluation shall be exactly the same as during measurement
of the test run (i.e. pressure, flow rates, filter settings on the analyzers and all other response time
influences). The response time determination shall be done with gas switching directly at the inlet of
the sample probe. The gas switching shall be done in less than 0,1 second. The gases used for the
test shall cause a concentration change of at least 60% FS.
The concentration trace of each single gas component shall be recorded. The response time is defined
as the difference in time between the gas switching and the appropriate change of the recorded
concentration. The system response time (t 90 ) consists of the delay time to the measuring detector and
the rise time of the detector. The delay time is defined as the time from the change (t 0 ) until the
response is 10% of the final reading (t 10 ). The rise time is defined as the time between 10% and 90%
response of the final reading (t 90 – t 10 ).
For time alignment of the analyzer and exhaust flow signals in the case of raw measurement, the
transformation time is defined as the time from the change (t 0 ) until the response is 50% of the final
reading (t 50 ).
The system response time shall be % 10 seconds with a rise time % 2,5 seconds for all limited
components (CO, NOx, HC) and all ranges used.
1.11.2. Calibration of tracer gas analyzer for exhaust flow measurement
The analyzer for measurement of the tracer gas concentration, if used, shall be calibrated using the
standard gas.
The calibration curve shall be established by at least 10 calibration points (excluding zero) spaced so
that a half of the calibration points are placed between 4% to 20% of analyzer's full scale and the rest
are in between 20% to 100% of the full scale. The calibration curve is calculated by the method of
least squares.
The calibration curve shall not differ by more than & 1% of the full scale from the nominal value of
each calibration point, in the range from 20% to 100% of the full scale. It shall also not differ by
more than & 2% from the nominal value in the range from 4% to 20% of the full scale.
The analyzer shall be set at zero and spanned prior to the test run using a zero gas and a span gas
whose nominal value is more than 80% of the analyzer full scale."
(h)
paragraph 2.2 shall be replaced by the following
"2.2. The calibration of gas flow-meters or flow measurement instrumentation shall be traceable to national and/or
international standards.
The maximum error of the measured value shall be within ± 2% of reading.
For partial flow dilution systems, the accuracy of the sample flow G SE is of special concern, if not measured directly,
but determined by differential flow measurement
G SE = G TOTW – G DILW
In this case an accuracy of & 2% for G TOTW and G DILW is not sufficient to guarantee acceptable accuracies of G SE. If
the gas flow is determined by differential flow measurement, the maximum error of the difference shall be such that
the accuracy of G SE is within & 5% when the dilution ratio is less than 15. It can be calculated by taking root-mean-
square of the errors of each instrument."
(i)
the following section shall be added
Additional calibration requirements for partial flow dilution systems
2.6.1. Periodical calibration
If the sample gas flow is determined by differential flow measurement the flow meter or the flow
measurement instrumentation shall be calibrated by one of the following procedures, such that the probe flow
G SE into the tunnel fulfils the accuracy requirements of Appendix I section 2.4
The flow meter for G DILW is connected in series to the flow meter for G TOTW , the difference between the two
flow meters is calibrated for at least 5 set points with flow values equally spaced between the lowest G DILW
value used during the test and the value of G TOTW used during the test The dilution tunnel may be bypassed.
A calibrated mass flow device is connected in series to the flowmeter for G TOTW and the accuracy is checked
for the value used for the test. Then the calibrated mass flow device is connected in series to the flow meter
for G DILW , and the accuracy is checked for at least 5 settings corresponding to the dilution ratio between 3 and
50, relative to G TOTW used during the test.
The transfer tube TT is disconnected from the exhaust, and a calibrated flow measuring device with a suitable
range to measure G SE is connected to the transfer tube. Then G TOTW is set to the value used during the test,
and G DILW is sequentially set to at least 5 values corresponding to dilution ratios q between 3 and 50.
Alternatively, a special calibration flow pathmay be provided, in which the tunnel is bypassed, but the total
and dilution air flow through the corresponding meters are maintained as in the actual test.
A tracer gas is fed into the transfer tube TT. This tracer gas may be a component of the exhaust gas, like CO 2
or NOx. After dilution in the tunnel the tracer gas component is measured. This shall be carried out for 5
dilution ratios between 3 and 50. The accuracy of the sample flow is determined from the dilution ration q
G SE = G TOTW /q
The accuracies of the gas analyzers shall be taken into account to guarantee the accuracy of G SE
Carbon flow check
A carbon flow check using actual exhaust is strongly recommended for detecting measurement and control
problems and verifying the proper operation of the partial flow dilution system. The carbon flow check
should be run at least each time a new engine is installed, or something significant is changed in the test cell
configuration.
The engine shall be operated at peak torque load and speed or any other steady-state mode that produces 5%
or more of CO 2 . The partial flow sampling system shall be operated with a dilution factor of about 15 to 1.
2.6.3. Pre-test check
A pre-test check shall be performed within 2 hours before the test run in the following way
The accuracy of the flow meters shall be checked by the same method as used for calibration for at least two
points, including flow values of G DILW that correspond to dilution ratios between 5 and 15 for the G TOTW value
used during the test.
If it can be demonstrated by records of the calibration procedure described above that the flow meter
calibration is stable over a longer period of time, the pre-test check may be omitted.
2.6.4. Determination of the transformation time
The system settings for the transformation time evaluation shall be exactly the same as during measurement
of the test run. The transformation time shall be determined by the following method
An independent reference flowmeter with a measurement range appropriate for the probe flow shall be put in
series with and closely coupled to the probe. This flow meter shall have a transformation time of less than
100 ms for the flow step size used in the response time measurement, with flow restriction sufficiently low
not to affect the dynamic performance of the partial flow dilution system, and consistent with good
engineering practice.
A step change shall be introduced to the exhaust flow (or air flow if exhaust flow is calculated) input of the
partial flow dilution system, from a low flow to at least 90% of full scale. The trigger for the step change
should be the same one as that used to start the look-ahead control in actual testing. The exhaust flow step
stimulus and the flowmeter response shall be recorded at a sample rate of at least 10 Hz.
From this data, the transformation time shall be determined for the partial flow dilution system, which is the
time from the initiation of the step stimulus to the 50% point of the flowmeter response. In a similar manner,
the transformation times of the G SE signal of the partial flow dilution system and of the G EXHW signal of the
exhaust flow meter shall be determined. These signals are used in the regression checks performed after each
test (Appendix I section 2.4).
The calculation shall be repeated for at least 5 rise and fall stimuli, and the results shall be averaged. The
internal transformation time (<100 ms) of the reference flowmeter shall be subtracted from this value. This is
the "look-ahead" value of the partial flow dilution system, which shall be applied in accordance with
Appendix I section 2.4."
the following section shall be added
CALIBRATION OF THE CVS SYSTEM
General
The CVS system shall be calibrated by using an accurate flowmeter and means to change operating conditions.
The flow through the system shall be measured at different flow operating settings, and the control parameters of the
system shall be measured and related to the flow.
Various type of flowmeters may be used, e.g. calibrated venturi, calibrated laminar flowmeter, calibrated
turbinemeter.
Calibration of the Positive Displacement Pump (PDP)
All the parameters related to the pump shall be simultaneously measured along with the parameters related to a
calibration venturi which is connected in series with the pump. The calculated flow rate (in m 3 /min at pump inlet,
absolute pressure and temperature) shall be plotted against a correlation function which is the value of a specific
combination of pump parameters. The linear equation which relates the pump flow and the correlation function shall
be determined. If a CVS has a multiple speed drive, the calibration shall be performed for each range used.
Temperature stability shall be maintained during calibration.
Leaks in all the connections and ducting between the calibration venturi and the CVS pump shall be maintained lower
than 0,3% of the lowest flow point (highest restriction and lowest PDP speed point).
3.2.1. Data Analysis
The air flowrate (Q s ) at each restriction setting (minimum 6 settings) shall be calculated in standard m 3 /min from the
flowmeter data using the manufacturer's prescribed method. The air flow rate shall then be converted to pump flow
(V 0 ) in m 3 /rev at absolute pump inlet temperature and pressure as follows
Q s T 101 . 3
x
x
V 0 $
n 273
p A
where,
= air flow rate at standard conditions (101,3 kPa, 273 K) (m 3 /s)
= temperature at pump inlet (K)
= absolute pressure at pump inlet (p B - p 1 ) (kPa)
= pump speed (rev/s)
To account for the interaction of pressure variations at the pump and the pump slip rate, the correlation function (X 0 )
between pump speed, pressure differential from pump inlet to pump outlet and absolute pump outlet pressure shall be
calculated as follows
1 x % p p
X 0 $
n
p A
where,
" p p
= pressure differential from pump inlet to pump outlet (kPa)
p A = absolute outlet pressure at pump outlet (kPa)
A linear least-square fit shall be performed to generate the calibration equation as follows
V 0 $ D 0 # m x ( X 0 )
D 0 and m are the intercept and slope constants, respectively, describing the regression lines.
For a CVS system with multiple speeds, the calibration curves generated for the different pump flow ranges shall be
approximately parallel, and the intercept values (D 0 ) shall increase as the pump flow range decreases.
The values calculated by the equation shall be within ± 0,5% of the measured value of V 0 . Values of m will vary
from one pump to another. Particulate influx over time will cause the pump slip to decrease, as reflected by lower
values for m. Therefore, calibration shall be performed at pump start-up, after major maintenance, and if the total
system verification (section 3.5) indicates a change in the slip rate.
Calibration of the Critical Flow Venturi (CFV)
Calibration of the CFV is based upon the flow equation for a critical venturi. Gas flow is a function of inlet pressure
and temperature, as shown below
K v x p A
Q s $
T
where,
K v = calibration coefficient
p A = absolute pressure at venturi inlet (kPa)
T = temperature at venturi inlet (K)
3.3.1. Data Analysis
The air flow rate (Q s ) at each restriction setting (minimum 8 settings) shall be calculated in standard m 3 /min from the
flowmeter data using the manufacturer's prescribed method. The calibration coefficient shall be calculated from the
calibration data for each setting as follows
Q S x T
K v $
p A
where,
Q s = air flow rate at standard conditions (101,3 kPa, 273 K) (m 3 /s)
T = temperature at the venturi inlet (K)
p A = absolute pressure at venturi inlet (kPa)
To determine the range of critical flow, K v shall be plotted as a function of venturi inlet pressure. For critical
(choked) flow, K v will have a relatively constant value. As pressure decreases (vacuum increases), the venturi
becomes unchoked and K v decreases, which indicates that the CFV is operated outside the permissible range.
For a minimum of eight points in the region of critical flow, the average K V and the standard deviation shall be
calculated. The standard deviation shall not exceed ± 0,3% of the average K V
Calibration of the Subsonic Venturi (SSV)
Calibration of the SSV is based upon the flow equation for a subsonic venturi. Gas flow is a function of inlet
pressure and temperature, pressure drop between the SSV inlet and throat, as shown below
% 1
( +
"
"
#
Q SSV / A 0 d 2 C d P A & r 1 . 4286 . r 1 . 7143 #
) ,
#
4 1 . 4286 )
& ' T
* , -
$ 1 . " r
where,
= collection of constants and units conversions
" 1 %
" m 3 % # K 2 & " 1 %
# #
& & #
& #
&
$ min ' # kPa & $ mm '
$
'
= 0,006111 in SI units
d
= diameter of the SSV throat (m)
C d
= discharge coefficient of the SSV
P A
= absolute pressure at venturi inlet (kPa)
T
= temperature at the venturi inlet (K)
$ P
= ratio of the SSV throat to inlet absolute, static pressure = 1 "
r
P A
d
ß
= ratio of the SSV throat diameter, d, to the inlet pipe inner diameter =
D
Data Analysis
The air flow rate (Q SSV ) at each flow setting (minimum 16 settings) shall be calculated in standard m 3 /min from the
flowmeter data using the manufacturer's prescribed method. The discharge coefficient shall be calculated from the
calibration data for each setting as follows
Q SSV
C d /
% 1
( +
"
"
#
A 0 d 2 P A & r 1 . 4286 . r 1 . 7143 #
) ,
#
4 1 . 4286 )
& ' T
* , -
$ 1 . " r
where,
Q SSV = air flow rate at standard conditions (101,3 kPa, 273 K), m 3 /s
T
= temperature at the venturi inlet, K
d
= diameter of the SSV throat, m
$ P
= ratio of the SSV throat to inlet absolute, static pressure = 1 "
r
P A
d
ß
= ratio of the SSV throat diameter, d, to the inlet pipe inner diameter =
D
To determine the range of subsonic flow, C d shall be plotted as a function of Reynolds number, at the SSV throat.
The Re at the SSV throat is calculated with the following formula
Q SSV
Re # A 1
d "
where,
= a collection of constants and units conversions
" 1 % " min % " mm %
= 25,55152 #
& #
& #
&
$ m ' $ s ' $ m '
= air flow rate at standard conditions (101,3 kPa, 273 K) (m 3 /s)
Q SSV
d
= diameter of the SSV throat (m)
µ
= absolute or dynamic viscosity of the gas, calculated with the following formula
bT 2
bT 2
" #
#
kg/m-s
S
S " T
1 "
T
where
kg
1 , 458 " 10
=
msK 2
b
= empirical constant
110 , 4 K
S
= empirical constant
=
Because Q SSV is an input to the Re formula, the calculations must be started with an initial guess for Q SSV or C d of the
calibration venturi, and repeated until Q SSV converges. The convergence method must be accurate to 0,1% or better.
For a minimum of sixteen points in the subsonic flow region, the calculated values of C d from the resulting
calibration curve fit equation must be within ± 0,5% of the measured C d for each calibration point.
Total System Verification
The total accuracy of the CVS sampling system and analytical system shall be determined by introducing a known
mass of a pollutant gas into the system while it is being operated in the normal manner. The pollutant is analysed,
and the mass calculated according to Annex III, Appendix 3, section 2.4.1 except in the case of propane where a
factor of 0,000472 is used in place of 0,000479 for HC. Either of the following two techniques shall be used.
3.5.1. Metering with a Critical Flow Orifice
A known quantity of pure gas (propane) shall be fed into the CVS system through a calibrated critical orifice. If the
inlet pressure is high enough, the flow rate, which is adjusted by means of the critical flow orifice, is independent of
the orifice outlet pressure (critical flow). The CVS system shall be operated as in a normal exhaust emission test for
about 5 to 10 minutes. A gas sample shall be analysed with the usual equipment (sampling bag or integrating
method), and the mass of the gas calculated. The mass so determined shall be within ± 3% of the known mass of the
gas injected.
3.5.2. Metering by Means of a Gravimetric Technique
The weight of a small cylinder filled with propane shall be determined with a precision of ± 0,01 g. For about 5 to 10
minutes, the CVS system shall be operated as in a normal exhaust emission test, while carbon monoxide or propane is
injected into the system. The quantity of pure gas discharged shall be determined by means of differential weighing.
A gas sample shall be analysed with the usual equipment (sampling bag or integrating method), and the mass of the
gas calculated. The mass so determined shall be within ± 3% of the known mass of the gas injected."
Appendix 3 shall be amended as follows
(a)
The following title for this Appendix shall be inserted: "DATA EVALUATION AND CALCULATIONS"
(b)
the title of section 1 shall read "DATA EVALUATION AND CALCULATIONS – NRSC TEST"
(c)
section 1.2 shall be replaced by the following
"1.2 Particulate emissions
For the evaluation of the particulates, the total sample masses (MSAM,i) through the filters shall be recorded
for each mode. The filters shall be returned to the weighing chamber and conditioned for at least one hour,
but not more than 80 hours, and then weighed. The gross weight of the filters shall be recorded and the tare
weight (see section 3.1, Annex III) subtracted. The particulate mass (Mf for single filter method; Mf,i for the
multiple filter method) is the sum of the particulate masses collected on the primary and back-up filters. If
background correction is to be applied, the dilution air mass (MDIL) through the filters and the particulate
mass (Md) shall be recorded. If more than one measurement was made, the quotient Md/MDIL must be
calculated for each single measurement and the values averaged."
(d)
section 1.3.1 shall be replaced by the following
"1.3.1.
Determination of the exhaust gas flow
The exhaust gas flow rate (G EXHW ,) shall be determined for each mode according to Annex III,
Appendix 1, sections 1.2.1 to 1.2.3.
When using a full flow dilution system, the total dilute exhaust gas flow rate (G TOTW ,) shall be
determined for each mode according to Annex III, Appendix 1, section 1.2.4."
(e)
sections 1.3.2 -1.4.6 shall be replaced by the following
Dry/wet correction (G EXHW ,) shall be determined for each mode according to Annex III, Appendix 1, sections
1.2.1 to 1.2.3.
When applying G EXHW the measured concentration shall be converted to a wet basis according to the
following formulae, if not already measured on a wet basis
conc (wet) = k w × conc (dry)
For the raw exhaust gas
#
&
K W , r , 1 * $
'
$ 1 ) 1 , 88 " 0 , 005 " " % CO " dry # ) % CO " dry # # ) K '
%
w 2 (
For the diluted gas
1 , 88 " CO 2 %( wet ) &
#
K W , e , 1 * $ $ 1 )
'
%
(
or
#
&
$
'
$
'
K W , e , 1 + $
1 , 88 " CO 2 %( dry ) '
$ $ 1 )
' '
%
(
For the dilution air
k W , d % 1 $ k W 1
1 , 608 " " H d " " 1 $ 1 / DF # # H a " " 1 / DF # #
k W 1 %
1000 # 1 , 608 " " H d " " 1 $ 1 / DF # # H a " " 1 / DF # #
6 , 22 " R d " p d
H d %
p B $ p d " R d " 10 " 2
For the intake air (if different from the dilution air)
k W , a % 1 $ k W 2
1 , 608 " H a
k W 2 %
1000 # " 1 , 608 " H a #
6 , 22 " R a " p a
H a %
p B $ p a " R a " 10 " 2
H a : absolute humidity of the intake air (g water per kg dry air)
H d : absolute humidity of the dilution air (g water per kg dry air)
R d : relative humidity of the dilution air (%)
R a : relative humidity of the intake air (%)
p d : saturation vapour pressure of the dilution air (kPa)
p a : saturation vapour pressure of the intake air (kPa)
p B : total barometric pressure (kPa).
H a and H d may be derived from relative humidity measurement, as described above, or from dewpoint
measurement, vapour pressure measurement or dry/wet bulb measurement using the generally
accepted formulae.
1.3.3. Humidity correction for NOx
As the NOx emission depends on ambient air conditions, the NO x concentration shall be corrected for ambient air
temperature and humidity by the factors K H given in the following formula
k H =
"
#
"
#
1 - 0,0182 " H a $ 10,71 # 0,0045 " T a $ 298
T a : temperatures of the air in (K)
H a : humidity of the intake air (g water per kg dry air)
6 , 220 " R a " p a
H a %
p B $ p a " R a " 10 " 2
R a : relative humidity of the intake air (%)
p a : saturation vapour pressure of the intake air (kPa)
p B : total barometric pressure (kPa).
H a may be derived from relative humidity measurement, as described above, or from dewpoint
measurement, vapour pressure measurement or dry/wet bulb measurement using the generally
accepted formulae.
1.3.4. Calculation of emission mass flow rates
The emission mass flow rates for each mode shall be calculated as follows
For the raw exhaust gas 1
(a)
Gas mass = u × conc × G EXHW
For the dilute exhaust gas 1
(b)
Gas mass = u × conc c × G TOTW
where
conc c is the background corrected concentration
conc c % conc $ conc d " " 1 $ " 1 / DF # #
"
#
DF % 13 , 4 / conc CO 2 # " conc CO # conc HC # " 10 " 4
or
DF=13,4/concCO 2
The coefficients u - wet shall be used according to Table 4
Table 4. Values of the coefficients u - wet for various exhaust components
Gas
u
conc
NO x
0,001587
ppm
CO
0,000966
ppm
HC
0,000479
ppm
CO 2
15,19
percent
The density of HC is based upon an average carbon to hydrogen ratio of 1:1,85.
1.3.5. Calculation of the specific emissions
The specific emission (g/kWh) shall be calculated for all individual components in the following way
n
" Gas
" WF i
mass i
i " 1
Individual gas #
n
" P " WF
i
i
i " 1
where P i = P m,i + P AE,i .
The weighting factors and the number of modes (n) used in the above calculation are according to Annex III, section
3.7.1.
Calculation of the particulate emission
The particulate emission shall be calculated in the following way
1.4.1. Humidity correction factor for particulates
As the particulate emission of diesel engines depends on ambient air conditions, the particulate mass flow rate shall
be corrected for ambient air humidity with the factor K p given in the following formula
K P % 1 / " 1 # 0 , 0133 " " H a $ 10 , 71 # #
In the case of NO x , the NO x concentration (NO x conc or NO x conc c ) has to be multiplied by K HNOx (humidity correction factor for NO x quoted
in section 1.3.3) as follows: K HNOx x conc or K HNOx x conc c
where
H a : humidity of the intake air, gram of water per kg dry air
6 , 220 " R a " p a
H a %
p B $ p a " R a " 10 " 2
where
R a : relative humidity of the intake air (%)
p a : saturation vapour pressure of the intake air (kPa)
p B : total barometric pressure (kPa)
NOTE
H a may be derived from relative humidity measurement, as described above, or from dewpoint
measurement, vapour pressure measurement or dry/wet bulb measurement using the generally
accepted formulae
Partial flow dilution system
The final reported test results of the particulate emission shall be derived through the following steps. Since
various types of dilution rate control may be used, different calculation methods for equivalent diluted
exhaust gas mass flow rate G EDF apply. All calculations shall be based upon the average values of the
individual modes (i) during the sampling period.
1.4.2.1. Isokinetic systems
G EDFW,i = G EXHW,i × q i
G DILW , i # " G EXHW , i " r #
q i $
" G
" r #
EXHW , i
where r corresponds to the ratio of the cross sectional areas of the isokinetic probe A p and exhaust pipe A T
A P
r "
A T
1.4.2.2. Systems with measurement of CO 2 or NO x concentration
G EDFW,i = G EXHW,i × q i
Conc E , i " Conc A , i
q i #
Conc D , i " Conc A , i
where
Conc E = wet concentration of the tracer gas in raw exhaust
Conc D = wet concentration of the tracer gas in the diluted exhaust
Conc A = wet concentration of the tracer gas in the dilution air
Concentrations measured on a dry basis shall be converted to a wet basis according to section 1.3.2. .
1.4.2.3. Systems with CO2 measurement and carbon balance method
206 , 6 " G FUEL , i
G EDFW , i $
CO 2 D , i # CO 2 A , i
where
CO 2D = CO 2 concentration of the diluted exhaust
CO 2A = CO 2 concentration of the dilution air
(concentrations in volume % on wet basis)
This equation is based upon the carbon balance assumption (carbon atoms supplied to the engine are emitted
as CO 2 ) and derived through the following steps
G EDFW,i = G EXHW,i × q i
and
206 , 6 " G FUEL , i
q i $
G EXHW , i " " CO 2 D , i # CO 2 A , i #
1.4.2.4. Systems with flow measurement
G EDFW,i = G EXHW,i × q i
G TOTW , i
q i #
" G
" G DILW , i #
TOTW , i
Full flow dilution system
The final reported test results of the particulate emission shall be derived through the following steps.
All calculations shall be based upon the average values of the individual modes (i) during the sampling
period.
G EDFW,i = G TOTW,i
Calculation of the particulate mass flow rate
The particulate mass flow rate shall be calculated as follows
For the single filter method
" G EDFW # aver
M f
PT mass #
"
M SAM
where
(G EDFW ) aver over the test cycle shall be determined by summation of the average values of the individual
modes during the sampling period
n
" G EDFW # aver # " G EDFW , i " WF i
i " 1
n
M SAM # " M SAM , i
i " 1
where i = 1, . . . n
For the multiple filter method
" G
#
M f , i
EDFW , i
aver
PT mass #
"
M SAM , i
where i = 1, . . . n
The particulate mass flow rate may be background corrected as follows
For single filter method
) ) , " G EDFW # aver
& M f
# M d
# i " n #
1 )
$
" WF i * * - "
$
" " 1 /
$
*
'
PT mass
/
' M SAM $ % M DIL $ % i " 1 $ % DF i * +
* * -
+ + .
(
If more than one measurement is made, (M d /M DIL ) shall be replaced with (M d /M DIL ) aver
"
#
DF $ 13 , 4 / concCO 2 # " concCO # concHC # " 10 " 4
or
DF=13,4/concCO 2
For multiple filter method
& M f , i
1 ) ) * , & G EDFW , i ,
# M d
#
/ $
" $ 1 /
* - " '
PT mass , i 0 '
-
' ( M SAM , i $ % M DIL $ % DF i * + * + - . ( ' 1000 . -
If more than one measurement is made, (M d /M DIL ) shall be replaced with (M d /M DIL ) aver
"
#
DF $ 13 , 4 / concCO 2 # " concCO # concHC # " 10 " 4
or
DF=13,4/concCO 2
Calculation of the specific emissions
The specific emission of particulates PT (g/kWh) shall be calculated in the following way 1
For the single filter method
PT mass
PT # n
" P " WF
i
i
i " 1
For the multiple filter method
n
" PT
" WF i
mass , i
i " 1
PT #
n
" P " WF
i
i
i " 1
Effective weighting factor
For the single filter method, the effective weighting factor WF E,i for each mode shall be calculated in the
following way
M SAM , i " " G EDFW # aver
WF E , i #
M SAM " " G EDFW , i #
where i = l, . . . n.
The value of the effective weighting factors shall be within ± 0,005 (absolute value) of the weighting factors
listed in Annex III, section 3.7.1."
(f)
The following section shall be inserted
DATA EVALUATION AND CALCULATIONS (NRTC TEST)
The two following measurement principles that can be used for the evaluation of pollutant emissions over the NRTC
cycle are described in this section
the gaseous components are measured in the raw exhaust gas on a real time basis, and the particulates are
determined using a partial flow dilution system;
–
the gaseous components and the particulates are determined using a full flow dilution system (CVS
system).
Calculation of gaseous emissions in the raw exhaust gas and of the particulate emissions with a partial flow
The particulate mass flow rate PT mass has to be multiplied by Kp (humidity correction factor for particulates quoted in section 1.4.1).
dilution system
Introduction
The instantaneous concentration signals of the gaseous components are used for the calculation of the mass
emissions by multiplication with the instantaneous exhaust mass flow rate. The exhaust mass flow rate may
be measured directly, or calculated using the methods described in Annex III, Appendix 1, section 2.2.3
(intake air and fuel flow measurement, tracer method, intake air and air/fuel ratio measurement). Special
attention shall be paid to the response times of the different instruments. These differences shall be accounted
for by time aligning the signals.
For particulates, the exhaust mass flow rate signals are used for controlling the partial flow dilution system to
take a sample proportional to the exhaust mass flow rate. The quality of proportionality is checked by
applying a regression analysis between sample and exhaust flow as described in Annex III, Appendix 1,
section 2.4.
Determination of the gaseous components
2.1.2.1. Calculation of mass emission
The mass of the pollutants M gas (g/test) shall be determined by calculating the instantaneous mass emissions
from the raw concentrations of the pollutants, the u values from Table 4 (see also Section 1.3.4) and the
exhaust mass flow, aligned for the transformation time and integrating the instantaneous values over the
cycle. Preferably, the concentrations should be measured on a wet basis. If measured on a dry basis, the
dry/wet correction as described here below shall be applied to the instantaneous concentration values before
any further calculation is done.
Table 4. Values of the coefficients u – wet for various exhaust components
Gas
u
conc
NO x
0,001587
ppm
CO
0,000966
ppm
HC
0,000479
ppm
CO 2
15,19
percent
The density of HC is based upon an average carbon to hydrogen ratio of 1:1,85.
The following formula shall be applied
i " n
" u " conc " G
M gas =
"
i
EXHW , i
f (in g/test)
i " 1
where
u
=
ratio between density of exhaust component and density of exhaust gas
conc i =
instantaneous concentration of the respective component in the raw exhaust gas (ppm)
G EXHW,i =
instantaneous exhaust mass flow (kg/s)
f
=
data sampling rate (Hz)
n
=
number of measurements
For the calculation of NO x , the humidity correction factor k H , as described here below, shall be used.
The instantaneously measured concentration shall be converted to a wet basis as described here below, if not
already measured on a wet basis
2.1.2.2. Dry/wet correction
If the instantaneously measured concentration is measured on a dry basis, it shall be converted to a wet basis
according to the following formulae
conc wet = k W x conc dry
#
&
K W , r , 1 * $
'
"
#
$ 1 ) 1 , 88 " 0 , 005 " conc CO ) conc CO ) K W 2 '
%
(
1,608 " H a
"
#
1000 # 1,608 * H a
dry CO 2 concentration (%)
dry CO concentration (%)
intake air humidity, (g water per kg dry air)
6 , 220 " R a " p a
H a $
p B # p a " R a " 10 " 2
R a : relative humidity of the intake air (%)
p a : saturation vapour pressure of the intake air (kPa)
p B : total barometric pressure (kPa)
H a may be derived from relative humidity measurement, as described above, or from
dewpoint measurement, vapour pressure measurement or dry/wet bulb measurement using the
generally accepted formulae.
2.1.2.3. NOx correction for humidity and temperature
As the NO x emission depends on ambient air conditions, the NO x concentration shall be corrected for
humidity and ambient air temperature with the factors given in the following formula
"
#
"
#
1 - 0,0182 " H a $ 10,71 # 0,0045 " T a $ 298
temperature of the intake air, K
humidity of the intake air,g water per kg dry air
6 , 220 " R a " p a
H a $
p B # p a " R a " 10 " 2
R a : relative humidity of the intake air (%)
p a : saturation vapour pressure of the intake air ( kPa)
p B : total barometric pressure (kPa)
H a may be derived from relative humidity measurement, as described above, or from
dewpoint measurement, vapour pressure measurement or dry/wet bulb measurement using the
generally accepted formulae.
2.1.2.4. Calculation of the specific emissions
The specific emissions (g/kWh) shall be calculated for each individual component in the following way
Individual gas =
M gas /W act
where
W act
=
actual cycle work as determined in Annex III Section 4.6.2 (kWh)
Particulate determination
2.1.3.1. Calculation of mass emission
The mass of particulates M PT (g/test) shall be calculated by either of the following methods
(a)
M f
M EDFW
M
#
"
PT
M SAM
where
M f
=
particulate mass sampled over the cycle (mg)
M SAM =
mass of diluted exhaust gas passing the particulate collection filters (kg)
M EDFW =
mass of equivalent diluted exhaust gas over the cycle (kg)
The total mass of equivalent diluted exhaust gas mass over the cycle shall be determined as follows
i " n
M EDFW # " G EDFW , i "
f
i " 1
G EDFW , i # G EXHW , i " q i
G TOTW , i
q i # "
G TOTW , i " G DILW , i % &'
#
$
where
G EDFW,i =
instantaneous equivalent diluted exhaust mass flow rate (kg/s)
G EXHW,i =
instantaneous exhaust mass flow rate (kg/s)
q i
=
instantaneous dilution ratio
G TOTW,I
=
instantaneous diluted exhaust mass flow rate through dilution tunnel (kg/s)
G DILW,i =
instantaneous dilution air mass flow rate (kg/s)
f
=
data sampling rate (Hz)
n
=
number of measurements
(b)
M f
M PT 0
r s x 1000
where
M f
=
particulate mass sampled over the cycle (mg)
r s
=
average sample ratio over the test cycle
where
M SE
M
" SAM
r s #
M EXHW M TOTW
M SE
=
sampled exhaust mass over the cycle (kg)
M EXHW =
total exhaust mass flow over the cycle (kg)
M SAM
=
mass of diluted exhaust gas passing the particulate collection filters (kg)
M TOTW =
mass of diluted exhaust gas passing the dilution tunnel (kg)
NOTE: In case of the total sampling type system, M SAM and M TOTW are identical.
2.1.3.2. Particulate correction factor for humidity
As the particulate emission of diesel engines depends on ambient air conditions, the particulate concentration
shall be corrected for ambient air humidity with the factor Kp given in the following formula.
k p "
" 1 # 0,0133 " " H a $ 10,71 # #
where
H a
=
humidity of the intake air in g water per kg dry air
6 , 220 " R a " p a
H a $
p B # p a " R a " 10 " 2
R a : relative humidity of the intake air (%)
p a : saturation vapour pressure of the intake air (kPa)
p B : total barometric pressure (kPa)
NOTE
H a may be derived from relative humidity measurement, as described above, or from
dewpoint measurement, vapour pressure measurement or dry/wet bulb measurement using the
generally accepted formulae.
2.1.3.3. Calculation of the specific emissions
The particulate emission (g/kWh) shall be calculated in the following way
PT # M PT " K p / W act
where
W act
=
actual cycle work as determined in Annex III Section 4.6.2(kWh)
Determination of gaseous and particulate components with a full flow dilution system
For calculation of the emissions in the diluted exhaust gas, it is necessary to know the diluted exhaust gas
mass flow rate. The total diluted exhaust gas flow over the cycle M TOTW (kg/test) shall be calculated from the
measurement values over the cycle and the corresponding calibration data of the flow measurement device
(V 0 for PDP, K V for CFV, C d for SSV): the corresponding methods described in section 2.2.1 may be used. If
the total sample mass of particulates (M SAM ) and gaseous pollutants exceeds 0,5% of the total CVS flow
(M TOTW ), the CVS flow shall be corrected for M SAM or the particulate sample flow shall be returned to the
CVS prior to the flow measuring device.
Determination of the Diluted Exhaust Gas Flow
PDP-CVS system
The calculation of the mass flow over the cycle, if the temperature of the diluted exhaust is kept within ± 6 K
over the cycle by using a heat exchanger, is as follows
M TOTW =
1,293 x V 0 x N P x (p B - p 1 ) x273 / (101,3 x T)
where
M TOTW =
mass of the diluted exhaust gas on wet basis over the cycle
=
volume of gas pumped per revolution under test conditions (m³/rev)
N P
=
total revolutions of pump per test
p B
=
atmospheric pressure in the test cell (kPa)
p 1
=
pressure drop below atmospheric at the pump inlet (kPa)
T
=
average temperature of the diluted exhaust gas at pump inlet over thecycle (K)
If a system with flow compensation is used (i.e. without heat exchanger), the instantaneous mass emissions
shall be calculated and integrated over the cycle. In this case, the instantaneous mass of the diluted exhaust
gas shall be calculated as follows
M TOTW,i =
1,293 x V 0 x N P,i x (p B - p 1 ) x 273 / (101,3 x T)
where
N P,i
=
total revolutions of pump per time interval
CFV-CVS system
The calculation of the mass flow over the cycle, if the temperature of the diluted exhaust gas is kept within ±
11K over the cycle by using a heat exchanger, is as follows
1,293 x t x K v x p A / T 0,5
M TOTW =
where
M TOTW =
mass of the diluted exhaust gas on wet basis over the cycle
t
=
cycle time (s)
K V
=
calibration coefficient of the critical flow venturi for standard conditions,
p A
=
absolute pressure at venturi inlet (kPa)
T
=
absolute temperature at venturi inlet (K)
If a system with flow compensation is used (i.e. without heat exchanger), the instantaneous mass emissions
shall be calculated and integrated over the cycle. In this case, the instantaneous mass of the diluted exhaust
gas shall be calculated as follows
1,293 x "t i x K V x p A / T 0,5
M TOTW,i =
where
"t i
=
time interval(s)
SSV-CVS system
The calculation of the mass flow over the cycle is as follows if the temperature of the diluted exhaust is kept
within ± 11 K over the cycle by using a heat exchanger
M TOTW 0 1 , 293 x Q SSV
where
& 1
) ,
#
"
#
Q SSV 0 A 0 d 2 C d P A ' r 1 . 4286 / r 1 . 7143 " $
* -
$
4 1 . 4286 *
' ( T
+ - .
% 1 / " r
= collection of constants and units conversions
" 1 %
" m % # K 2 & " 1 %
= 0,006111 in SI units of #
# min & & # kPa & # mm 2 &
& $
'
$
' #
$
'
d = diameter of the SSV throat (m)
C d = discharge coefficient of the SSV
P A = absolute pressure at venturi inlet (kPa)
T = temperature at the venturi inlet (K)
# P
r = ratio of the SSV throat to inlet absolute, static pressure = 1 "
P A
d
ß = ratio of the SSV throat diameter, d, to the inlet pipe inner diameter =
D
If a system with flow compensation is used (i.e. without heat exchanger), the instantaneous mass emissions
shall be calculated and integrated over the cycle. In this case, the instantaneous mass of the diluted exhaust
gas shall be calculated as follows
M TOTW 0 1 , 293 x Q SSV x 1 t i
where
% 1
( +
"
Q SSV 0 A 0 d 2 C d P A x & " r 1 . 4286 / r 1 . 7143 # #
) ,
# 1 / " 4 r 1 . 4286 ) ,
& ' T
$
* -
"t i
=
time interval (s)
The real time calculation shall be initialized with either a reasonable value for C d , such as 0.98, or a
reasonable value of Q ssv . If the calculation is initialized with Q ssv , the initial value of Q ssv shall be used to
evaluate Re.
During all emissions tests, the Reynolds number at the SSV throat must be in the range of Reynolds numbers
used to derive the calibration curve developed in Appendix 2 section 3.2.
NOx Correction for Humidity
As the NOx emission depends on ambient air conditions, the NO x concentration shall be corrected for ambient
air humidity with the factors given in the following formulae.
k H
=
"
#
"
#
1 - 0,0182 " H a $ 10,71 # 0,0045 " T a $ 298
where
T a = temperature of the air (K)
Ha = humidity of the intake air (g water per kg dry air)
in which,
6 , 220 x R a x p a
H a 0
"
p B / p a x R a x 10 2
R a
=
relative humidity of the intake air (%)
p a
=
saturation vapour pressure of the intake air (kPa)
p B
=
total barometric pressure (kPa)
NOTE
H a may be derived from relative humidity measurement, as described above, or from
dewpoint measurement, vapour pressure measurement or dry/wet bulb measurement using the
generally accepted formulae.
Calculation of the Emission Mass Flow
2.2.3.1. Systems with Constant Mass Flow
For systems with heat exchanger, the mass of the pollutants M GAS (g/test) shall be determined from the
following equation
M GAS = u x conc x M TOTW
where
u
=
ratio between density of the exhaust component and density of diluted exhaust gas, as
reported in Table 4, point 2.1.2.1
conc =
average background corrected concentrations over the cycle from integration (mandatory for
NO x and HC) or bag measurement (ppm)
M TOTW =
total mass of diluted exhaust gas over the cycle as determined in section 2.2.1 (kg)
As the NO x emission depends on ambient air conditions, the NO x concentration shall be corrected for ambient
air humidity with the factor k H , as described in section 2.2.2.
Concentrations measured on a dry basis shall be converted to a wet basis in accordance with section 1.3.2
Determination of the Background Corrected Concentrations
The average background concentration of the gaseous pollutants in the dilution air shall be subtracted from
measured concentrations to get the net concentrations of the pollutants. The average values of the
background concentrations can be determined by the sample bag method or by continuous measurement with
integration. The following formula shall be used.
conc
=
conc e - conc d x (1 - (1/DF))
where,
conc
=
concentration of the respective pollutant in the diluted exhaust gas, corrected by the amount of
the respective pollutant contained in the dilution air (ppm)
conc e =
concentration of the respective pollutant measured in the diluted exhaust gas (ppm)
conc d =
concentration of the respective pollutant measured in the dilution air (ppm)
DF
=
dilution factor
The dilution factor shall be calculated as follows
13 , 4
DF =
conc e CO 2 . ( conc e HC . conc eCO ) x 10 " 4
2.2.3.2. Systems with Flow Compensation
For systems without heat exchanger, the mass of the pollutants M GAS (g/test) shall be determined by
calculating the instantaneous mass emissions and integrating the instantaneous values over the cycle. Also,
the background correction shall be applied directly to the instantaneous concentration value. The following
formulae shall be applied
n
M GAS $ " " M TOTW , i " conc e , i " u # # " M TOTW " conc d " " 1 # 1 / DF # " u #
i " 1
where
conc e,i =
instantaneous concentration of the respective pollutant measured in the diluted
exhaust gas (ppm)
conc d =
concentration of the respective pollutant measured in the dilution air (ppm)
u
=
ratio between density of the exhaust component and density of diluted exhaust gas, as
reported in Table 4, point 2.1.2.1
M TOTW,i =
instantaneous mass of the diluted exhaust gas (section 2.2.1) (kg)
M TOTW =
total mass of diluted exhaust gas over the cycle (section 2.2.1) (kg)
DF
=
dilution factor as determined in point 2.2.3.1.1.
As the NO x emission depends on ambient air conditions, the NO x concentration shall be corrected for ambient
air humidity with the factor k H , as described in section 2.2.2.
Calculation of the Specific Emissions
The specific emissions (g/kWh) shall be calculated for each individual component in the following way
Individual gas = M gas /W act
where
W act
=
actual cycle work as determined in Annex III Section 4.6.2 (kWh)
Calculation of the particulate emission
2.2.5.1. Calculation of the Mass Flow
The particulate mass M PT (g/test) shall be calculated as follows
M f x M TOTW
M SAM 1000
M PT
=
M f
=
particulate mass sampled over the cycle (mg)
M TOTW =
total mass of diluted exhaust gas over the cycle as determined in section 2.2.1 (kg)
M SAM =
mass of diluted exhaust gas taken from the dilution tunnel for collecting particulates (kg)
and,
M f
=
M f,p + M f,b , if weighed separately (mg)
M f,p
=
particulate mass collected on the primary filter (mg)
M f,b
=
particulate mass collected on the back-up filter (mg)
If a double dilution system is used, the mass of the secondary dilution air shall be subtracted from the total
mass of the double diluted exhaust gas sampled through the particulate filters.
M SAM =
M TOT - M SEC
where
M TOT =
mass of double diluted exhaust gas through particulate filter (kg)
M SEC
=
mass of secondary dilution air (kg)
If the particulate background level of the dilution air is determined in accordance with Annex III, section
4.4.4, the particulate mass may be background corrected. In this case, the particulate mass (g/test) shall be
calculated as follows
% M f
1 ( ( + M TOTW
" M d "
. # #
) ) ) ) , x
x # 1 .
&
#
M PT =
M
M
DF
* * - , 1000
$
' & SAM $ DIL
where
M f , M SAM , M TOTW =
see above
mass of primary dilution air sampled by background particulate sampler (kg)
mass of the collected background particulates of the primary dilution air (mg)
dilution factor as determined in section 2.2.3.1.1
2.2.5.2. Particulate correction factor for humidity
As the particulate emission of diesel engines depends on ambient air conditions, the particulate concentration
shall be corrected for ambient air humidity with the factor Kp given in the following formula.
k p "
" 1 # 0,0133 " " H a $ 10,71 # #
= humidity of the intake air in g water per kg dry air
6 , 220 " R a " p a
H a $
p B # p a " R a " 10 " 2
R a : relative humidity of the intake air (%)
p a : saturation vapour pressure of the intake air (kPa)
p B : total barometric pressure (kPa)
H a may be derived from relative humidity measurement, as described above, or from
dewpoint measurement, vapour pressure measurement or dry/wet bulb measurement using the
generally accepted formulae.
2.2.5.3. Calculation of the Specific Emission
The particulate emission (g/kWh) shall be calculated in the following way
PT # M PT " K p / W act
actual cycle work, as determined in Annex III Section 4.6.2 (kWh)"
The following Appendices shall be added
"APPENDIX 4
NRTC ENGINE DYNAMOMETER SCHEDULE
Time
Norm. Norm.
Time
Norm. Norm.
Time
Norm. Norm.
(s)
Speed Torque
(s)
Speed Torque
(s)
Speed Torque
(%)
(%)
(%)
(%)
(%)
(%)
Time
Norm.
Norm.
Time
Norm. Norm.
Time
Norm.
Norm.
(s)
Speed Torque
(s)
Speed Torque
(s)
Speed Torque
(%)
(%)
(%)
(%)
(%)
(%)
Time
Norm.
Norm.
Time
Norm. Norm.
Time
Norm.
Norm.
(s)
Speed Torque
(s)
Speed Torque
(s)
Speed Torque
(%)
(%)
(%)
(%)
(%)
(%)
Time
Norm.
Norm.
Time
Norm. Norm.
Time
Norm.
Norm.
(s)
Speed Torque
(s)
Speed Torque
(s)
Speed Torque
(%)
(%)
(%)
(%)
(%)
(%)
Time
Norm.
Norm.
Time
Norm. Norm.
Time
Norm.
Norm.
(s)
Speed Torque
(s)
Speed Torque
(s)
Speed Torque
(%)
(%)
(%)
(%)
(%)
(%)
Time
Norm.
Norm.
Time
Norm. Norm.
Time
Norm.
Norm.
(s)
Speed Torque
(s)
Speed Torque
(s)
Speed Torque
(%)
(%)
(%)
(%)
(%)
(%)
Time
Norm.
Norm.
Time
Norm. Norm.
Time
Norm.
Norm.
(s)
Speed Torque
(s)
Speed Torque
(s)
Speed Torque
(%)
(%)
(%)
(%)
(%)
(%)
Time
Norm.
Norm.
Time
Norm. Norm.
Time
Norm.
Norm.
(s)
Speed Torque
(s)
Speed Torque
(s)
Speed Torque
(%)
(%)
(%)
(%)
(%)
(%)
Time
Norm.
Norm.
Time
Norm.
Norm.
Time
Norm.
Norm.
(s)
Speed
Torque
(s)
Speed
Torque
(s)
Speed
Torque
(%)
(%)
(%)
(%)
(%)
(%)
A graphical display of the NRTC dynamometer schedule is shown below
NRTC dynamometer schedule
Speed (%)
Torque (%)
time [ s ]
APPENDIX 5
DURABILITY REQUIREMENTS
1. EMISSION DURABILITY PERIOD AND DETERIORATION FACTORS.
This appendix shall apply to CI engines Stage IIIA and IIIB and IV only.
Manufacturers shall determine a Deterioration Factor (DF) value for each regulated pollutant for all Stage IIIA and
IIIB engine families. Such DFs shall be used for type approval and production line testing.
Test to establish DF's shall be conducted as follows
The manufacturer shall conduct durability tests to accumulate engine operating hours according to a test schedule that
is selected on the basis of good engineering judgement to be representative of in-use engine operation in respect to
characterizing emission performance deterioration. The durability test period should typically represent the
equivalent of at least one quarter of the Emission Durability Period (EDP).
Service accumulation operating hours may be acquired through running engines on a dynamometer test bed or from
actual in-field machine operation. Accelerated durability tests can be applied whereby the service accumulation test
schedule is performed at a higher load factor than typically experienced in the field. The acceleration factor relating
the number of engine durability test hours to the equivalent number of EDP hours shall be determined by the engine
manufacturer based on good engineering judgement.
During the period of the durability test, no emission sensitive components can be serviced or replaced other than to
the routine service schedule recommended by the manufacturer.
The test engine, subsystems, or components to be used to determine exhaust emission DF's for an engine family, or
for engine families of equivalent emission control system technology, shall be selected by the engine manufacturer on
the basis of good engineering judgement. The criteria is that the test engine should represent the emission
deterioration characteristic of the engine families that will apply the resulting DF values for certification approval.
Engines of different bore and stroke, different configuration, different air management systems, different fuel systems
can be considered as equivalent in respect to emissions deterioration characteristics if there is a reasonable technical
basis for such determination.
DF values from another manufacturer can be applied if there is a reasonable basis for considering technology
equivalence with respect to emissions deterioration, and evidence that the tests have been carried according to the
specified requirements.
Emissions testing will be performed according to the procedures defined in this Directive for the test engine after
initial run-in but before any service accumulation, and at the completion of the durability. Emission tests can also be
performed at intervals during the service accumulation test period, and applied in determining the deterioration trend.
The service accumulation tests or the emissions tests performed to determine deterioration must not be witnessed by
the approval authority.
1.1.1.3. Determination of DF values from Durability Tests
An additive DF is defined as the value obtained by subtraction of the emission value determine at the beginning of
the EDP, from the emissions value determined to represent the emission performance at the end of the EDP.
A multiplicative DF is defined as the emission level determined for the end of the EDP divided by the emission value
recorded at the beginning of the EDP.
Separate DF values shall be established for each of the pollutants covered by the legislation. In the case of
establishing a DF value relative to the NOx+HC standard, for an additive DF, this is determined based on the sum of
the pollutants notwithstanding that a negative deterioration for one pollutant may not offset deterioration for the
other. For a multiplicative NOx+HC DF, separate HC and NOx DF's shall be determined and applied separately
when calculating the deteriorated emission levels from an emissions test result before combining the resultant
deteriorated NOx and HC values to esatablish compliance with the standard.
In cases where the testing is not conducted for the full EDP, the emission values at the end of the EDP is determined
by extrapolation of the emission deterioration trend established for the test period, to the full EDP.
When emissions test results have been recorded periodically during the service accumulation durability testing,
standard statistical processing techniques based on good practice shall be applied to determine the emission levels at
the end of the EDP; statistical significance testing can be applied in the determination of the final emissions values.
If the calculation results in a value of less than 1.00 for a multiplicative DF, or less than 0.00 for an additive DF, then
the DF shall be 1.0 or 0.00, respectively.
A manufacturer may, with the approval of the type approval authority, use DF values established from results of
durability tests conducted to obtain DF values for certification of on-road HD CI engines. This will be allowed if
there is technological equivalency between the test on-road engine and the non-road engine families applying the DF
values for certification. The DF values derived from on-road engine emission durability test results, must be
calculated on the basis of EDP values defined in section 2.
In the case where an engine family uses established technology, an analysis based on good engineering practices may
be used in lieu of testing to determine a deterioration factor for that engine family subject to approval of the type
approval authority.
DF information in approval applications
Additive DF's shall be specified for each pollutant in an engine family certification application for CI engines not
using any aftertreatment device.
Multiplicative DF's shall be specified for each pollutant in an engine family certification application for CI engines
using an aftertreatment device.
The manufacture shall furnish the Type Approval agency on request with information to support the DF values. This
would typically include emission test results, service accumulation test schedule, maintenance procedures together
with information to support engineering judgements of technological equivalency, if applicable.
2. EMISSION DURABILITY PERIODS FOR STAGE IIIA, IIIB AND IV ENGINES.
Manufacturers shall use the EDP in Table 1 of this section.
Table 1: EDP categories for CI Stage IIIA, IIIB and IV Engines (hours)
Category (power
Useful life (hours)
band)
EDP
3.000
" 37 kW
(constant speed
engines)
5.000
" 37 kW
(not constant speed
engines)
8.000
# 37 kW
Engines for the use in
10.000
inland waterway
vessels
10.000
Railcar engines
3. ANNEX V SHALL BE AMENDED AS FOLLOWS
The heading shall be replaced by the following
"TECHNICAL CHARACTERISTICS OF REFERENCE FUEL PRESCRIBED FOR APPROVAL TESTS AND TO
VERIFY CONFORMITY OF PRODUCTION
NON-ROAD MOBILE MACHINERY REFERENCE FUEL FOR CI ENGINES TYPE APPROVED TO MEET STAGE I
and II LIMIT VALUES AND FOR ENGINES TO BE USED IN INLAND WATERWAY VESSELS."
The following text shall be inserted after the current table on reference fuel for diesel as follows
"NON-ROAD MOBILE MACHINERY REFERENCE FUEL FOR CI ENGINES TYPE APPROVED TO MEET STAGE IIIA
LIMIT VALUES.
Limits 1
Parameter
Unit
Test Method
Minimum
Maximum
Cetane number 2
54,0
EN-ISO 5165
kg/m 3
Density at 15°C
EN-ISO 3675
Distillation
50% point
°C
-
EN-ISO 3405
95% point
°C
EN-ISO 3405
- Final boiling point
°C
-
EN-ISO 3405
Flash point
°C
-
EN 22719
CFPP
°C
-
-5
EN 116
mm 2 /s
Viscosity at 40°C
2,5
3,5
EN-ISO 3104
Polycyclic aromatic hydrocarbons
% m/m
3,0
6,0
IP 391
Sulphur content 3
mg/kg
-
ASTM D 5453
Copper corrosion
-
class 1
EN-ISO 2160
Conradson carbon residue (10% DR)
% m/m
-
0,2
EN-ISO 10370
Ash content
% m/m
-
0,01
EN-ISO 6245
Water content
% m/m
-
0,05
EN-ISO 12937
Neutralisation (strong acid) number
mg KOH/g
-
0,02
ASTM D 974
Oxidation stability 4
mg/ml
-
0,025
EN-ISO 12205
The values quoted in the specifications are "true values". In establishment of their limit values the terms of ISO 4259
"Petroleum products – Determination and application of precision data in relation to methods of test" have been applied and
in fixing a minimum value, a minimum difference of 2R above zero has been taken into account; in fixing a maximum and
minimum value, the minimum difference is 4R (R = reproducibility).
Notwithstanding this measure, which is necessary for technical reasons, the manufacturer of fuels should nevertheless aim at
a zero value where the stipulated maximum value is 2R and at the mean value in the case of quotations of maximum and
minimum limits. Should it be necessary to clarify the questions as to whether a fuel meets the requirements of the
specifications, the terms of ISO 4259 should be applied.
The range for cetane number is not in accordance with the requirements of a minimum range of 4R. However, in the case of
a dispute between fuel supplier and fuel user, the terms of ISO 4259 may be used to resolve such disputes provided replicate
measurements, of sufficient number to archive the necessary precision, are made in preference to single determinations.
The actual sulphur content of the fuel used for the test shall be reported. .
Even though oxidation stability is controlled, it is likely that shelf life will be limited. Advice should be sought from the
supplier as to storage conditions and life.
NON-ROAD MOBILE MACHINERY REFERENCE FUEL FOR CI ENGINES TYPE APPROVED TO MEET STAGE IIIB AND
IV LIMIT VALUES.
Limits 1
Parameter
Unit
Test Method
Minimum
Maximum
Cetane number 2
54,0
EN-ISO 5165
kg/m 3
Density at 15°C
EN-ISO 3675
Distillation
50% point
°C
-
EN-ISO 3405
95% point
°C
EN-ISO 3405
- Final boiling point
°C
-
EN-ISO 3405
Flash point
°C
-
EN 22719
CFPP
°C
-
-5
EN 116
mm 2 /s
Viscosity at 40°C
2,3
3,3
EN-ISO 3104
Limits 1
Parameter
Unit
Test Method
Minimum
Maximum
Polycyclic aromatic hydrocarbons
% m/m
3,0
6,0
IP 391
Sulphur content 3
mg/kg
-
ASTM D 5453
Copper corrosion
-
class 1
EN-ISO 2160
Conradson carbon residue (10% DR)
% m/m
-
0,2
EN-ISO 10370
Ash content
% m/m
-
0,01
EN-ISO 6245
Limits (1)
Parameter
Unit
Test Method
Minimum
maximum
Water content
% m/m
-
0,02
EN-ISO 12937
Neutralisation (strong acid) number
mg KOH/g
-
0,02
ASTM D 974
Oxidation stability (4)
mg/ml
-
0,025
EN-ISO 12205
Lubricity (HFRR wear scar diameter at
µm
-
CEC F-06-A-96
60°C)
FAME
prohibited
The values quoted in the specifications are "true values". In establishment of their limit values the terms of ISO 4259
"Petroleum products – Determination and application of precision data in relation to methods of test" have been applied and
in fixing a minimum value, a minimum difference of 2R above zero has been taken into account; in fixing a maximum and
minimum value, the minimum difference is 4R (R = reproducibility).
Notwithstanding this measure, which is necessary for technical reasons, the manufacturer of fuels should nevertheless aim at
a zero value where the stipulated maximum value is 2R and at the mean value in the case of quotations of maximum and
minimum limits. Should it be necessary to clarify the questions as to whether a fuel meets the requirements of the
specifications, the terms of ISO 4259 should be applied.
The range for cetane number is not in accordance with the requirements of a minimum range of 4R. However, in the case of
a dispute between fuel supplier and fuel user, the terms of ISO 4259 may be used to resolve such disputes provided replicate
measurements, of sufficient number to archive the necessary precision, are made in preference to single determinations.
The actual sulphur content of the fuel used for the Type I test shall be reported.
Even though oxidation stability is controlled, it is likely that shelf life will be limited. Advice should be sought from the
supplier as to storage conditions and life."
4. ANNEX VII SHALL BE AMENDED AS FOLLOWS
APPENDIX 1 SHALL BE REPLACED BY THE FOLLOWING
"Appendix 1
TEST RESULTS FOR COMPRESSION IGNITION ENGINES
TEST RESULTS
INFORMATION CONCERNING THE CONDUCT OF THE NRSC TEST 1
1. Reference fuel used for test
1.1.1. Cetane number: ……………………………………………………………..
1.1.2. Sulphur content: …………………………………………………………….
1.1.3. Density ………………………………………………………………………
Lubricant
1.2.1. Make(s): ……………………………………………………………………..
1.2.2.Type(s): ………………………………………………………………………
(state percentage of oil in mixture if lubricant and fuel are mixed)
Engine driven equipment (if applicable)
1.3.1. Enumeration and identifying details: ………………………………………..
1.3.2. Power absorbed at indicated engine speeds (as specified by the manufacturer)
Power P AE (kW) absorbed at various engine speeds 1 , taking into account Appendix 3
of this Annex
Rated
Intermediate (if applicable)
Must not be greater than 10% of the power measured during the test.
Engine performance
1.4.1. Engine speeds
Idle: . ……………………………………………………………………….…….rpm
Intermediate: ……………………………………………………………………. rpm
Rated: …………………………………………………………………………… rpm
For the case of several parent engines to be indicated for each of them.
1.4.2. Engine power 1
Power setting (kW) at various engine speeds
Condition
Intermediate (if applicable)
Maximum power measured on test (P M )
(kW) (a)
Total power absorbed by engine driven equipment as per
section 1.3.2 of this Appendix, or section 3.1 of Annex III (P AE )
(kW) (b)
Net engine power as specified in section 2.4 of Annex I (kW)
(c)
c = a + b
1.5.
Emission levels
1.5.1.
Dynamometer setting (kW)
Dynamometer setting (kW) at various engine speeds
Percent Load
Intermediate (if applicable)
Rated
10 (if applicable)
25 (if applicable)
1.5.2. Emission results on the NRSC test
CO: . ……………..g/kWh
HC: . ……………..g/kWh
NOx: . ……………g/kWh
NMHC+NOx: …....g/kWh
Particulates: . ……..g/kWh
1.5.3.
Sampling system used for the NRSC test
1.5.3.1. Gaseous emissions 1 :…………………………………………………...
1.5.3.2. Particulates 1 :……………………………………………………………
Method 2 : single/multiple filter
1.5.3.2.1.
INFORMATION CONCERNING THE CONDUCT OF THE NRTC TEST 3
2.
2.1.
Emission results on the NRTC test
CO: . ……………..g/kWh
NMHC: …………..g/kWh
NOx: . ……………g/kWh
Particulates: . ……..g/kWh
NMHC+NOx : ……g/kWh
Uncorrected power measured in accordance with section 2.4 of Annex I.
Indicate figure numbers defined in Annex VI section 1.
Delete as appropriate.
For the case of several parent engines, to be indicated for each of them.
Sampling system used for the NRTC test
Gaseous emissions 1 :…………………………………………………...
Particulates 1 :……………………………………………………………
Method 2 : single/multiple filter
5. ANNEX XII SHALL BE AMENDED AS FOLLOWS
The following section shall be added
For engines categories H, I, and J (stage IIIA) and engines category K, L and M (stage IIIB) as defined in Article 9
section 3, the following type-approvals and, where applicable, the pertaining approval marks are recognised as being
equivalent to an approval to this Directive;
Type-approvals to Directive 88/77/EEC, as amended by Directive 99/96/EC, which are in compliance with stages B1,
B2 or C provided for in Article 2 and section 6.2.1 of Annex I.
UN-ECE Regulation 49.03 series of amendments which are in compliance with stages B1, B2 and C provided for in
paragraph 5.2."
ANNEX II
"Annex VI
ANALYTICAL AND SAMPLING SYSTEM
1. GASEOUS AND PARTICULATE SAMPLING SYSTEMS
Figure Number
Description
Exhaust gas analysis system for raw exhaust
Exhaust gas analysis system for dilute exhaust
Partial flow, isokinetic flow, suction blower control, fractional sampling
Partial flow, isokinetic flow, pressure blower control, fractional sampling
Partial flow, CO 2 or NO x control, fractional sampling
Partial flow, CO 2 or carbon balance, total sampling
Partial flow, single venturi and concentration measurement, fractional sampling
Partial flow, twin venturi or orifice and concentration measurement, fractional sampling
Partial flow, multiple tube splitting and concentration measurement, fractional sampling
Partial flow, flow control, total sampling
Partial flow, flow control, fractional sampling
Full flow, positive displacement pump or critical flow venturi, fractional sampling
Particulate sampling system
Dilution system for full flow system
Determination of the gaseous emissions
Section 1.1.1 and Figures 2 and 3 contain detailed descriptions of the recommended sampling and analysing systems. Since
various configurations can produce equivalent results, exact conformance with these figures is not required. Additional
components such as instruments, valves, solenoids, pumps and switches may be used to provide additional information and
coordinate the functions of the component systems. Other components which are not needed to maintain the accuracy on
some systems, may be excluded if their exclusion is based upon good engineering judgement.
1.1.1. Gaseous exhaust components CO, CO 2 , HC, NOx
An analytical system for the determination of the gaseous emissions in the raw or diluted exhaust gas is described based on
the use of
–
HFID analyser for the measurement of hydrocarbons,
–
NDIR analysers for the measurement of carbon monoxide and carbon dioxide,
–
HCLD or equivalent analyser for the measurement of nitrogen oxide.
For the raw exhaust gas (Figure 2), the sample for all components may be taken with one sampling probe or with two
sampling probes located in close proximity and internally split to the different analysers. Care must be taken that no
condensation of exhaust components (including water and sulphuric acid) occurs at any point of the analytical system.
For the diluted exhaust gas (Figure 3), the sample for the hydrocarbons shall be taken with another sampling probe than the
sample for the other components. Care must be taken that no condensation of exhaust components (including water and
sulphuric acid) occurs at any point of the analytical system.
Figure 2
Flow diagram of exhaust gas analysis system for CO, NOx and HC
HSL1
zero gas
HSL1
zero gas
vent
HC
P
zero gas
span gas
SP1
vent
air
fuel
P
FL1
optional 2 sampling probes
SL
HSL2
vent
vent
zero gas
FL5
FL4
zero gas
CO
vent
B
span gas
C
NO
FL6
zero gas
span gas
CO
vent
vent
FL7
span gas
vent
zero gas
FL2
O
FL8
span gas
Figure 3
Flow diagram of dilute exhaust gas analysis system for CO, CO 2 , NOx and HC
to PSS see figure 14
HSL1
HSL1
zero gas
BK
vent
HC
P
span gas
zero gas
HSL2
vent
air
fuel
P
FL1
SL
BK
vent
vent
zero gas
FL5
zero gas
FL4
CO
vent
span gas
C
NO
zero gas
FL6
span gas
CO
vent
span gas
vent
FL2
FL3
Descriptions – Figures 2 and 3
General statement
All components in the sampling gas path must be maintained at the temperature specified for the respective systems.
SP1 raw exhaust gas sampling probe (Figure 2 only)
A stainless steel straight closed and multihole probe is recommended. The inside diameter shall not be greater than
the inside diameter of the sampling line. The wall thickness of the probe shall not be greater than 1 mm. There shall
be a minimum of three holes in three different radial planes sized to sample approximately the same flow. The probe
must extend across at least 80% of the diameter of the exhaust pipe.
SP2 dilute exhaust gas HC sampling probe (Figure 3 only)
The probe shall
be defined as the first 254 mm to 762 mm of the hydrocarbon sampling line (HSL3),
have a 5 mm minimum inside diameter,
be installed in the dilution tunnel DT (section 1.2.1.2) at a point where the dilution air and exhaust gas are
well mixed (i.e. approximately 10 tunnel diameters downstream of the point where the exhaust enters the
dilution tunnel),
be sufficiently distant (radially) from other probes and the tunnel wall so as to be free from the influence of
any wakes or eddies,
be heated so as to increase the gas stream temperature to 463 K (190°C) ± 10 K at the exit of the probe.
SP3 dilute exhaust gas CO, CO 2 , NOx sampling probe (Figure 3 only)
The probe shall
be in the same plane as SP2,
be sufficiently distant (radially) from other probes and the tunnel wall so as to be free from the influence of
any wakes or eddies,
be heated and insulated over its entire length to a minimum temperature of 328 K (55°C) to prevent water
condensation.
HSL1 heated sampling line
The sampling line provides gas sampling from a single probe to the split point(s) and the HC analyser.
The sampling line shall
have a 5 mm minimum and a 13,5 mm maximum inside diameter,
be made of stainless steel or PTFE,
maintain a wall temperature of 463 (190°C) ± 10 K as measured at every separately controlled heated section,
if the temperature of the exhaust gas at the sampling probe is equal or below 463 K (190°C),
maintain a wall temperature greater than 453 K (180°C) if the temperature of the exhaust gas at the sampling
probe is above 463 K (190°C),
maintain a gas temperature of 463 K (190°C) ± 10 K immediately before the heated filter (F2) and the HFID.
HSL2 heated NO x sampling line
The sampling line shall
maintain a wall temperature of 328 to 473 K (55 to 200°C) up to the converter when using a cooling bath, and
up to the analyser when a cooling bath is not used,
be made of stainless steel or PTFE.
Since the sampling line need only be heated to prevent condensation of water and sulphuric acid, the
samplingline temperature will depend on the sulphur content of the fuel.
SL sampling line for CO (CO 2 )
The line shall be made of PTFE or stainless steel. It may be heated or unheated.
BK background bag (optional; Figure 3 only)
For the measurement of the background concentrations.
BG sample bag (optional; Figure 3 CO and CO 2 only)
For the measurement of the sample concentrations.
F1 heated pre-filter (optional)
The temperature shall be the same as HSL1.
F2 heated filter
The filter shall extract any solid particles from the gas sample prior to the analyser. The temperature shall be the
same as HSL1. The filter shall be changed as needed.
P heated sampling pump
The pump shall be heated to the temperature of HSL1.
Heated flame ionization detector (HFID) for the determination of the hydrocarbons. The temperature shall be kept at
453 to 473 K (180 to 200°C).
CO, CO 2
NDIR analysers for the determination of carbon monoxide and carbon dioxide.
NO 2
(H)CLD analyser for the determination of the oxides of nitrogen. If a HCLD is used it shall be kept at a temperature
of 328 to 473 K (55 to 200°C).
C converter
A converter shall be used for the catalytic reduction of NO 2 to NO prior to analysis in the CLD or HCLD.
B cooling bath
To cool and condense water from the exhaust sample. The bath shall be maintained at a temperature of 273 to 277 K
(0 to 4°C) by ice or refrigeration. It is optional if the analyser is free from water vapour interference as determined in
Annex III, Appendix 2, sections 1.9.1 and 1.9.2.
Chemical dryers are not allowed for removing water from the sample.
T1, T2, T3 temperature sensor
To monitor the temperature of the gas stream.
T4 temperature sensor
Temperature of the NO 2 -NO converter.
T5 temperature sensor
To monitor the temperature of the cooling bath.
G1, G2, G3 pressure gauge
To measure the pressure in the sampling lines.
R1, R2 pressure regulator
To control the pressure of the air and the fuel, respectively, for the HFID.
R3, R4, R5 pressure regulator
To control the pressure in the sampling lines and the flow to the analysers.
FL1, FL2, FL3 flow meter
To monitor the sample bypass flow.
FL4 to FL7 flow meter (optional)
To monitor the flow rate through the analysers.
V1 to V6 selector valve
Suitable valving for selecting sample, span gas or zero gas flow to the analyser.
V7, V8 solenoid valve
To bypass the NO 2 -NO converter.
V9 needle valve
To balance the flow through the NO 2 -NO converter and the bypass.
V10, V11 needle valve
To regulate the flows to the analysers.
V12, V13 toggle valve
To drain the condensate from the bath B.
V14 selector valve
Selecting the sample or background bag.
Determination of the particulates
Sections 1.2.1 and 1.2.2 and Figures 4 to 15 contain detailed descriptions of the recommended dilution and sampling
systems. Since various configurations can produce equivalent results, exact conformance with these figures is not
required. Additional components such as instruments, valve, solenoids, pumps and switches may be used to provide
additional information and coordinate the functions of the component systems. Other components which are not needed
to maintain the accuracy on some systems, may be excluded if their exclusion is based on good engineering judgement.
Dilution system
Partial flow dilution system (Figures 4 to 12) 1
A dilution system is described based on the dilution of a part of the exhaust stream. Splitting of the exhaust stream and
the following dilution process may be done by different dilution system types. For subsequent collection of the
particulates, the entire dilute exhaust gas or only a portion of the dilute exhaust gas may be passed to the particulate
sampling system (section 1.2.2, Figure 14). The first method is referred to as total sampling type, the second method as
fractional sampling type.
The calculation of the dilution ratio depends on the type of system used.
The following types are recommended
isokinetic systems (Figures 4 and 5)
With these systems, the flow into the transfer tube is matched to the bulk exhaust flow in terms of gas velocity
and/or pressure, thus requiring an undisturbed and uniform exhaust flow at the sampling probe. This is usually
achieved by using a resonator and a straight approach tube upstream of the sampling point. The split ratio is then
calculated from easily measurable values like tube diameters. It should be noted that isokinesis is only used for
matching the flow conditions and not for matching the size distribution. The latter is typically not necessary, as
the particles are sufficiently small as to follow the fluid streamlines,
flow controlled systems with concentration measurement (Figures 6 to 10)
With these systems, a sample is taken from the bulk exhaust stream by adjusting the dilution air flow and the total
dilution exhaust flow. The dilution ratio is determined from the concentrations of tracer gases, such as CO 2 or
NOx, naturally occurring in the engine exhaust. The concentrations in the dilution exhaust gas and in the dilution
air are measured, whereas the concentration in the raw exhaust gas can be either measured directly or determined
from fuel flow and the carbon balance equation, if the fuel composition is known. The systems may be controlled
by the calculated dilution ratio (Figures 6 and 7) or by the flow into the transfer tube (Figures 8, 9 and 10),
flow controlled systems with flow measurement (Figures 11 and 12)
With these systems, a sample is taken from the bulk exhaust stream by setting the dilution air flow and the total
dilution exhaust flow. The dilution ratio is determined from the difference of the two flow rates. Accurate
calibration of the flow meters relative to one another is required, since the relative magnitude of the two flow
rates can lead to significant errors at higher dilution ratios. Flow control is very straightforward by keeping the
dilute exhaust flow rate constant and varying the dilution air flow rate, if needed.
In order to realise the advantages of the partial flow dilution systems, attention must be paid to avoiding the
potential problems of loss of particulates in the transfer tube, ensuring that a representative sample is taken from
the engine exhaust, and determination of the split ratio.
The systems described pay attention to these critical areas.
Figures 4 to 12 show many types of partial flow dilution systems, which normally can be used for the steady-state test (NRSC). But, because
of very severe constraints of the transient tests, only those partial flow dilution systems (Figures 4 to 12) able to fulfill all the requirements
quoted in the section "Partial flow dilution system specifications" of Annex III, Appendix 1, Section 2.4, are accepted for the transient test
Figure 4
Partial flow dilution system with isokinetic probe and fractional sampling (SB control)
SB
DAF
PB
FM1
l > 10*d
PSP
d
vent
DT
PTT
TT
to particulate
see figure 14
sampling
system
ISP
DPT
delta p
EP
FC1
exhaust
Raw exhaust gas is transferred from the exhaust pipe to EP to the dilution tunnel DT through the transfer tube TT by the
isokinetic sampling probe ISP. The differential pressure of the exhaust gas between exhaust pipe and inlet to the probe is
measured with the pressure transducer DPT. This signal is transmitted to the flow controller FC1 that controls the
suction blower SB to maintain a differential pressure of zero at the tip of the probe. Under these conditions, exhaust gas
velocities in EP and ISP are identical, and the flow through ISP and TT is a constant fraction (split) of the exhaust gas
flow. The split ratio is determined from the cross sectional areas of EP and ISP. The dilution air flow rate is measured
with the flow measurement device FM1. The dilution ratio is calculated from the dilution air flow rate and the split ratio.
Figure 5
Partial flow dilution system with isokinetic probe and fractional sampling (PB control)
DAF
FM1
l > 10*d
SB
vent
PSP
d
DT
TT
PTT
see figure 14
to particulate
sampling
system
ISP
PB
EP
DPT
FC1
exhaust
delta p
Raw exhaust gas is transferred from the exhaust pipe EP to the dilution tunnel DT through the transfer tube TT by the
isokinetic sampling probe ISP. The differential pressure of the exhaust gas between exhaust pipe and inlet to the probe is
measured with the pressure transducer DPT. This signal is transmitted to the flow controller FC1 that controls the pressure
blower PB to maintain a differential pressure of zero at the tip of the probe. This is done by taking a small fraction of the
dilution air whose flow rate has already been measured with the flow measurement device FM1, and feeding it to TT by
means of a pneumatic orifice. Under these conditions, exhaust gas velocities in EP and ISP are identical, and the flow
through ISP and TT is a constant fraction (split) of the exhaust gas flow. The split ratio is determined from the cross
sectional areas of EP and ISP. The dilution air is sucked through DT by the suction blower SB, and the flow rate is measured
with FM1 at the inlet to DT. The dilution ratio is calculated from the dilution air flow rate and the split ratio.
Figure 6
Partial flow dilution system with CO 2 or NOx concentration measurement
and fractional sampling
FC2
EGA
EGA
optional
SB
DAF
l > 10*d
to PB or SB
d
PSP
vent
PB
DT
PTT
TT
see figure 14
to particulate
sampling
system
EGA
SP
EP
exhaust
Raw exhaust gas is transferred from the exhaust pipe EP to the dilution tunnel DT through the sampling probe SP and the
transfer tube TT. The concentrations of a tracer gas (CO 2 or NOx) are measured in the raw and diluted exhaust gas as
well as in the dilution air with the exhaust gas analyser(s) EGA. These signals are transmitted to the flow controller FC2
that controls either the pressure blower PB or the suction blower SB to maintain the desired exhaust split and dilution
ratio in DT. The dilution ratio is calculated from the tracer gas concentrations in the raw exhaust gas, the diluted exhaust
gas, and the dilution air.
Figure 7
Partial flow dilution system with CO 2 concentration measurement, carbon balance
and total sampling
FC2
EGA
EGA
optional to P
DAF
PTT
d
PB
DT
PSS
TT
FH
G FUEL
optional from FC2
P
SP
EP
details see figure 15
exhaust
Raw exhaust gas is transferred from the exhaust pipe EP to the dilution tunnel DT through the sampling probe SP and the
transfer tube TT. The CO 2 concentrations are measured in the diluted exhaust gas and in the dilution air with the exhaust
gas analyser(s) EGA. The CO 2 and fuel flow GFUEL signals are transmitted either to the flow controller FC2, or to the
flow controller FC3 of the particulate sampling system (Figure 14). FC2 controls the pressure blower PB, while FC3
controls the particulate sampling system (Figure 14), thereby adjusting the flows into and out of the system so as to
maintain the desired exhaust split and dilution ratio in DT. The dilution ratio is calculated from the CO 2 concentrations
and GFUEL using the carbon balance assumption.
Figure 8
Partial flow dilution system with single venturi, concentration measurement
and fractional sampling
EGA
EGA
l > 10*d
DAF
PB
VN
d PSP
vent
PTT
DT
TT
see figure 14
to particulate
sampling
system
SP
EP
EGA
exhaust
Raw exhaust gas is transferred from the exhaust pipe EP to the dilution tunnel DT through the sampling probe SP and the
transfer tube TT due to the negative pressure created by the venturi VN in DT. The gas flow rate through TT depends on
the momentum exchange at the venturi zone, and is therefore affected by the absolute temperature of the gas at the exit of
TT. Consequently, the exhaust split for a given tunnel flow rate is not constant, and the dilution ratio at low load is
slightly lower than at high load. The tracer gas concentrations (CO 2 or NOx) are measured in the raw exhaust gas, the
diluted exhaust gas, and the dilution air with the exhaust gas analyser(s) EGA, and the dilution ratio is calculated from the
values so measured.
Figure 9
Partial flow dilution system twin venturi or twin orifice,
concentration measurement and fractional sampling
EGA
EGA
DAF
PCV2
l > 10*d
HE
d
PSP
PB
DT
PTT
see figure 14
to particulate
PCV1
TT
sampling
SB
system
EP
vent
FD1
FD2
EGA
exhaust
Raw exhaust gas is transferred from the exhaust pipe EP to the dilution tunnel DT through the sampling probe SP and the
transfer tube TT by a flow divider that contains a set of orifices or venturis. The first one (FD1) is located in EP, the
second one (FD2) in TT. Additionally, two pressure control valves (PCV1 and PCV2) are necessary to maintain a
constant exhaust split by controlling the backpressure in EP and the pressure in DT. PCV1 is located downstream of SP
in EP, PCV2 between the pressure blower PB and DT. The tracer gas concentrations (CO 2 or NOx) are measured in the
raw exhaust gas, the diluted exhaust gas, and the dilution air with the exhaust gas analyser(s) EGA. They are necessary
for checking the exhaust split, and may be used to adjust PCV1 and PCV2 for precise split control. The dilution ratio is
calculated from the tracer gas concentrations.
Figure 10
Partial flow dilution system with multiple tube splitting,
concentration measurement and fractional sampling
EGA
EGA
DAF
l > 10*d
HE
d
DT
PSP
PTT
see figure 14
SB
to particulate
fresh air injection
sampling
system
EGA
TT
FC1
DAF
vent
DPT
FD3
air
DC
Raw exhaust gas is transferred from the exhaust pipe EP to the dilution tunnel DT through the transfer tube TT by the
flow divider FD3 that consists of a number of tubes of the same dimensions (same diameter, length and bed radius)
installed in EP. The exhaust gas through one of these tubes is lead to DT, and the exhaust gas through the rest of the
tubes is passed through the damping chamber DC. Thus, the exhaust split is determined by the total number of tubes. A
constant split control requires a differential pressure of zero between DC and the outlet of TT, which is measured with the
differential pressure transducer DPT. A differential pressure of zero is achieved by injecting fresh air into DT at the
outlet of TT. The tracer gas concentrations (CO 2 or NOx) are measured in the raw exhaust gas, the diluted exhaust gas,
and the dilution air with the exhaust gas analyser(s) EGA. They are necessary for checking the exhaust split and may be
used to control the injection air flow rate for precise split control. The dilution ratio is calculated from the tracer gas
concentrations.
Figure 11
Partial flow dilution system with flow control and total sampling
FC2
DAF
optional to P (PSS)
PTT
d
FM1
DT
PSS
TT
FH
GEXH
P
or
SP
vent
GAIR
or
EP
details see figure 15
GFUEL
exhaust
Raw exhaust gas is transferred from the exhaust pipe EP to the dilution tunnel DT through the sampling probe SP and the
transfer tube TT. The total flow through the tunnel is adjusted with the flow controller FC3 and the sampling pump P of
the particulate sampling system (Figure 16).
The dilution air flow is controlled by the flow controller FC2, which may use G EXH , G AIR or G FUEL as command signals,
for the desired exhaust split. The sample flow into DT is the difference of the total flow and the dilution air flow. The
dilution air flow rate is measured with flow measurement device FM1, the total flow rate with the flow measurement
device FM3 of the particulate sampling system (Figure 14). The dilution ratio is calculated from these two flow rates.
Figure 12
Partial flow dilution system with flow control and fractional sampling
FC2
to PB
or SB
l > 10*d
SB
d PSP
DT
FM1
PB
PTT
TT
FM2
see figure 14
to particulate
sampling
system
see figure 14
SP
EP
vent
exhaust
Raw exhaust gas is transferred from the exhaust pipe EP to the dilution tunnel DT through the sampling probe SP and the
transfer tube TT. The exhaust split and the flow into DT is controlled by the flow controller FC2 that adjusts the flows
(or speeds) of the pressure blower PB and the suction blower SB, accordingly. This is possible since the sample taken
with the particulate sampling system is returned into DT. GEXH, GAIR or GFUEL may be used as command signals for
FC2. The dilution air flow rate is measured with the flow measurement device FM1, the total flow with the flow
measurement device FM2. The dilution ratio is calculated from these two flow rates.
Description - Figures 4 to 12
EP exhaust pipe
The exhaust pipe may be insulated. To reduce the thermal inertia of the exhaust pipe a thickness to diameter ratio
of 0,015 or less is recommended. The use of flexible sections shall be limited to a length to diameter ratio of 12
or less. Bends will be minimised to reduce inertial deposition. If the system includes a test bed silencer, the
silencer may also be insulated.
For an isokinetic system, the exhaust pipe must be free of elbows, bends and sudden diameter changes for at least
six pipe diameters upstream and three pipe diameters downstream of the tip of the probe. The gas velocity at the
sampling zone must be higher than 10 m/s except at idle mode. Pressure oscillations of the exhaust gas must not
exceed ± 500 Pa on the average. Any steps to reduce pressure oscillations beyond using a chassis-type exhaust
system (including silencer and after-treatment device) must not alter engine performance nor cause the deposition
of particulates.
For systems without isokinetic probes, it is recommended to have a straight pipe of six pipe diameters upstream
and three pipe diameters downstream of the tip of the probe.
SP sampling probe (Figures 6 to 12)
The minimum inside diameter shall be 4 mm. The minimum diameter ratio between exhaust pipe and probe shall
be four. The probe shall be an open tube facing upstream on the exhaust pipe centre-line, or a multiple hole
probe as described under SP1 in section 1.1.1.
ISP isokinetic sampling probe (Figures 4 and 5)
The isokinetic sampling probe must be installed facing upstream on the exhaust pipe centre-line where the flow
conditions in section EP are met, and designed to provide a proportional sample of the raw exhaust gas. The
minimum inside diameter shall be 12 mm.
A control system is necessary for isokinetic exhaust splitting by maintaining a differential pressure of zero
between EP and ISP. Under these conditions exhaust gas velocities in EP and ISP are identical and the mass flow
through ISP is a constant fraction of the exhaust gas flow. The ISP has to be connected to a differential pressure
transducer. The control to provide a differential pressure of zero between EP and ISP is done with blower speed
or flow controller.
FD1, FD2 flow divider (Figure 9)
A set of venturis or orifices is installed in the exhaust pipe EP and in the transfer tube TT, respectively, to provide
a proportional sample of the raw exhaust gas. A control system consisting of two pressure control valves PCV1
and PCV2 is necessary for proportional splitting by controlling the pressures in EP and DT.
FD3 flow divider (Figure 10)
A set of tubes (multiple tube unit) is installed in the exhaust pipe EP to provide a proportional sample of the raw
exhaust gas. One of the tubes feeds exhaust gas to the dilution tunnel DT, whereas the other tubes exit exhaust
gas to a damping chamber DC. The tubes must have the same dimensions (same diameter, length, bend radius),
so that the exhaust split depends on the total number of tubes. A control system is necessary for proportional
splitting by maintaining a differential pressure of zero between the exit of the multiple tube unit into DC and the
exit of TT. Under these conditions, exhaust gas velocities in EP and FD3 are proportional, and the flow TT is a
constant fraction of the exhaust gas flow. The two points have to be connected to a differential pressure
transducer DPT. The control to provide a differential pressure of zero is done with the flow controller FC1.
EGA exhaust gas analyser (Figures 6 to 10)
CO 2 or NOx analysers may be used (with carbon balance method CO 2 only). The analysers shall be calibrated
like the analysers for the measurement of the gaseous emissions. One or several analysers may be used to
determine the concentration differences.
The accuracy of the measuring systems has to be such that the accuracy of G EDFW,i is within ± 4%.
TT transfer tube (Figures 4 to 12)
The particulate sample transfer tube shall be
–
as short as possible, but not more than 5 m in length,
–
equal to or greater than the probe diameter, but not more than 25 mm in diameter,
–
exiting on the centre-line of the dilution tunnel and pointing down-stream.
If the tube is 1 metre or less in length, it is to be insulated with material with a maximum thermal conductivity of
0,05 W/(m · K) with a radial insulation thickness corresponding to the diameter of the probe. If the tube is longer
than 1 metre, it must be insulated and heated to a minimum wall temperature of 523 K (250°C).
Alternatively, the transfer tube wall temperatures required may be determined through standard heat transfer
calculations.
DPT differential pressure transducer (Figures 4, 5 and 10)
The differential pressure transducer shall have a range of ± 500 Pa or less.
FC1 flow controller (Figures 4, 5 and 10)
For the isokinetic systems (Figures 4 and 5) a flow controller is necessary to maintain a differential pressure of
zero between EP and ISP. The adjustment can be done by
(a)
controlling the speed or flow of the suction blower (SB) and keeping the speed of the pressure blower
(PB) constant during each mode (Figure 4);
or
(b)
adjusting the suction blower (SB) to a constant mass flow of the diluted exhaust and controlling the flow
of the pressure blower PB, and therefore the exhaust sample flow in a region at the end of the transfer
tube (TT) (Figure 5).
In the case of a pressure controlled system the remaining error in the control loop must not exceed ± 3 Pa. The
pressure oscillations in the dilution tunnel must not exceed ± 250 Pa on average.
For a multi-tube system (Figure 10) a flow controller is necessary for proportional exhaust splitting to maintain a
differential pressure of zero between the outlet of the multi-tube unit and the exit of TT. The adjustment can be done by
controlling the injection air flow rate into DT at the exit of TT.
PCV1, PCV2 pressure control valve (Figure 9)
Two pressure control valves are necessary for the twin venturi/twin orifice system for proportional flow
splitting by controlling the backpressure of EP and the pressure in DT. The valves shall be located downstream
of SP in EP and between PB and DT.
DC damping chamber (Figure 10)
A damping chamber shall be installed at the exit of the multiple tube unit to minimize the pressure oscillations in
the exhaust pipe EP.
VN venturi (Figure 8)
A venturi is installed in the dilution tunnel DT to create a negative pressure in the region of the exit of the transfer
tube TT. The gas flow rate through TT is determined by the momentum exchange at the venturi zone, and is
basically proportional to the flow rate of the pressure blower PB leading to a constant dilution ratio. Since the
momentum exchange is affected by the temperature at the exit of TT and the pressure difference between EP and
DT, the actual dilution ratio is slightly lower at low load than at high load.
FC2 flow controller (Figures 6, 7, 11 and 12; optional)
A flow controller may be used to control the flow of the pressure blower PB and/or the suction blower SB. It
may be connected to the exhaust flow or fuel flow signal and/or to the CO 2 or NO x differential signal.
When using a pressurized air supply (Figure 11) FC2 directly controls the air flow.
FM1 flow measurement device (Figures 6, 7, 11 and 12)
Gas meter or other flow instrumentation to measure the dilution air flow. FM1 is optional if PB is calibrated to
measure the flow.
FM2 flow measurement device (Figure 12)
Gas meter or other flow instrumentation to measure the diluted exhaust gas flow. FM2 is optional if the suction
blower SB is calibrated to measure the flow.
PB pressure blower (Figures 4, 5, 6, 7, 8, 9 and 12)
To control the dilution air flow rate, PB may be connected to the flow controllers FC1 or FC2. PB is not required
when using a butterfly valve. PB may be used to measure the dilution air flow, if calibrated.
SB suction blower (Figures 4, 5, 6, 9, 10 and 12)
For fractional sampling systems only. SB may be used to measure the dilute exhaust gas flow, if calibrated.
DAF dilution air filter (Figures 4 to 12)
It is recommended that the dilution air be filtered and charcoal scrubbed to eliminate background hydrocarbons.
The dilution air shall have a temperature of 298 K (25°C) ± 5 K.
At the manufacturer's request the dilution air shall be sampled according to good engineering practice to
determine the background particulate levels, which can then be subtracted from the values measured in the
diluted exhaust.
PSP particulate sampling probe (Figures 4, 5, 6, 8, 9, 10 and 12)
The probe is the leading section of PTT and
–
shall be installed facing upstream at a point where the dilution air and exhaust gas are well mixed, i.e. on
the dilution tunnel DT centre-line of the dilution systems approximately 10 tunnel diameters downstream
of the point where the exhaust enters the dilution tunnel,
–
shall be 12 mm in minimum inside diameter,
–
may be heated to no greater than 325 K (52°C) wall temperature by direct heating or by dilution air pre-
heating, provided the air temperature does not exceed 325 K (52°C) prior to the introduction of the
exhaust in the dilution tunnel,
–
may be insulated.
–
DT dilution tunnel (Figures 4 to 12)
The dilution tunnel
–
shall be of a sufficient length to cause complete mixing of the exhaust and dilution air under turbulent
flow conditions,
–
shall be constructed of stainless steel with
–
a thickness to diameter ratio of 0,025 or less for dilution tunnels of greater than 75 mm inside
diameter,
–
a nominal wall thickness of not less than 1,5 mm for dilution tunnels of equal to or less than 75
mm inside diameter,
–
shall be at least 75 mm in diameter for the fractional sampling type,
–
is recommended to be at least 25 mm in diameter for the total sampling type.
–
may be heated to no greater than 325 K (52°C) wall temperature by direct heating or by dilution air pre-
heating, provided the air temperature does not exceed 325 K (52°C) prior to the introduction of the
exhaust in the dilution tunnel.
–
may be insulated.
The engine exhaust shall be thoroughly mixed with the dilution air. For fractional sampling systems, the mixing quality
shall be checked after introduction into service by means of a CO 2 profile of the tunnel with the engine running (at least
four equally spaced measuring points). If necessary, a mixing orifice may be used.
NOTE: If the ambient temperature in the vicinity of the dilution tunnel (DT) is below 293 K (20°C), precautions should
be taken to avoid particle losses onto the cool walls of the dilution tunnel. Therefore, heating and/or
insulating the tunnel within the limits given above is recommended.
At high engine loads, the tunnel may be cooled by a non-aggressive means such as a circulating fan, as long as the
temperature of the cooling medium is not below 293 K (20°C).
–
HE heat exchanger (Figures 9 and 10)
The heat exchanger shall be of sufficient capacity to maintain the temperature at the inlet to the suction blower SB within
± 11 K of the average operating temperature observed during the test.
Full flow dilution system (Figure 13)
A dilution system is described based upon the dilution of the total exhaust using the constant volume sampling (CVS)
concept. The total volume of the mixture of exhaust and dilution air must be measured. Either a PDP or a CFV or a SSV
system may be used.
For subsequent collection of the particulates, a sample of the dilute exhaust gas is passed to the particulate sampling
system (section 1.2.2, Figures 14 and 15). If this is done directly, it is referred to as single dilution. If the sample is
diluted once more in the secondary dilution tunnel, it is referred to as double dilution. This is useful, if the filter face
temperature requirement cannot be met with single dilution. Although partly a dilution system, the double dilution
system is described as a modification of a particulate sampling system in section 1.2.2, (Figure 15), since it shares most
of the parts with a typical particulate sampling system.
The gaseous emissions may also be determined in the dilution tunnel of a full flow dilution system. Therefore, the
sampling probes for the gaseous components are shown in Figure 13 but do not appear in the description list. The
respective requirements are described in section 1.1.1.
Descriptions (Figure 13)
EP exhaust pipe
The exhaust pipe length from the exit of the engine exhaust manifold, turbocharger outlet or after-treatment
device to the dilution tunnel is required to be not more than 10 m. If the system exceeds 4 m in length, then all
tubing in excess of 4 m shall be insulated, except for an in-line smoke-meter, if used. The radial thickness of the
insulation must be at least 25 mm. The thermal conductivity of the insulating material must have a value no
greater than 0,1 W/(m · K) measured at 673 K (400°C). To reduce the thermal inertia of the exhaust pipe a
thickness to diameter ratio of 0,015 or less is recommended. The use of flexible sections shall be limited to a
length to diameter ratio of 12 or less.
Figure 13
Full flow dilution system
see Figure 3
to exhaust gas
to background filter
analysis system
HE optional
PSP
PTT
EP
exhaust
optional
see figure 14
PDP
to particulate sampling system
or to DDS see figure 15
CFV or
FC3
SSV
if EFC is used
vent
vent
FC3
The total amount of raw exhaust gas is mixed in the dilution tunnel DT with the dilution air. The diluted exhaust
gas flow rate is measured either with a positive displacement pump PDP or with a critical flow venturi CFV or
with a sub-sonic venturi SSV. A heat exchanger HE or electronic flow compensation EFC may be used for
proportional particulate sampling and for flow determination. Since particulate mass determination is based on
the total diluted exhaust gas flow, the dilution ratio is not required to be calculated.
PDP positive displacement pump
The PDP meters total diluted exhaust flow from the number of the pump revolutions and the pump displacement.
The exhaust system back pressure must not be artificially lowered by the PDP or dilution air inlet system. Static
exhaust back pressure measured with the CVS system operating shall remain within ± 1,5 kPa of the static
pressure measured without connection to the CVS at identical engine speed and load.
The gas mixture temperature immediately ahead of the PDP shall be within ± 6 K of the average operating
temperature observed during the test, when no flow compensation is used.
Flow compensation can only be used if the temperature at the inlet of the PDP does not exceed 50°C (323 K).
CFV critical flow venturi
CFV measures total diluted exhaust flow by maintaining the flow at choked conditions (critical flow). Static
exhaust backpressure measured with the CFV system operating shall remain within ± 1,5 kPa of the static
pressure measured without connection to the CFV at identical engine speed and load. The gas mixture
temperature immediately ahead of the CFV shall be within ± 11 K of the average operating temperature observed
during the test, when no flow compensation is used.
SSV sub-sonic venturi
SSV measures total diluted exhaust flow as a function of inlet pressure, inlet temperature, pressure drop between
the SSV inlet and throat. Static exhaust backpressure measured with the SSV system operating shall remain
within ± 1,5 kPa of the static pressure measured without connection to the SSV at identical engine speed and
load. The gas mixture temperature immediately ahead of the SSV shall be within ± 11 K of the average operating
temperature observed during the test, when no flow compensation is used.
HE heat exchanger (optional if EFC is used)
The heat exchanger shall be of sufficient capacity to maintain the temperature within the limits required above.
EFC electronic flow compensation (optional if HE is used)
If the temperature at the inlet to either the PDP or CFV or SSV is not kept within the limits stated above, a flow
compensation system is required for continuous measurement of the flow rate and control of the proportional
sampling in the particulate system. To that purpose, the continuously measured flow rate signals are used to
correct the sample flow rate through the particulate filters of the particulate sampling system (Figures 14 and 15),
accordingly.
DT dilution tunnel
The dilution tunnel
–
shall be small enough in diameter to cause turbulent flow (Reynolds number greater than 4000) of
sufficient length to cause complete mixing of the exhaust and dilution air. A mixing orifice may be used,
–
shall be at least 75 mm in diameter,
–
may be insulated.
The engine exhaust shall be directed downstream at the point where it is introduced into the dilution tunnel, and
thoroughly mixed.
When using single dilution, a sample from the dilution tunnel is transferred to the particulate sampling system
(section 1.2.2, Figure 14). The flow capacity of the PDP or CFV or SSV must be sufficient to maintain the
diluted exhaust at a temperature of less than or equal to 325 K (52°C) immediately before the primary particulate
filter.
When using double dilution, a sample from the dilution tunnel is transferred to the secondary dilution tunnel
where it is further diluted, and then passed through the sampling filters (section 1.2.2, Figure 15). The flow
capacity of the PDP or CFV or SSV must be sufficient to maintain the diluted exhaust stream in the DT at a
temperature of less than or equal to 464 K (191°C) at the sampling zone. The secondary dilution system must
provide sufficient secondary dilution air to maintain the doubly-diluted exhaust stream at a temperature of less
than or equal to 325 K (52°C) immediately before the primary particulate filter.
DAF dilution air filter
It is recommended that the dilution air be filtered and charcoal scrubbed to eliminate background hydrocarbons.
The dilution air shall have a temperature of 298 K (25°C) ± 5 K. At the manufacturer's request the dilution air
shall be sampled according to good engineering practice to determine the background particulate levels, which
can then be subtracted from the values measured in the diluted exhaust.
PSP particulate sampling probe
The probe is the leading section of PTT and
–
shall be installed facing upstream at a point where the dilution air and exhaust gas are well mixed, i.e. on
the dilution tunnel DT centre-line of the dilution systems approximately 10 tunnel diameters downstream
of the point where the exhaust enters the dilution tunnel,
–
shall be 12 mm in minimum inside diameter,
–
may be heated to no greater than 325 K (52°C) wall temperature by direct heating or by dilution air pre-
heating, provided the air temperature does not exceed 325 K (52°C) prior to the introduction of the
exhaust in the dilution tunnel,
–
may be insulated.
1.2.2.
Particulate sampling system (Figures 14 and 15)
The particulate sampling system is required for collecting the particulates on the particulate filter. In the case of total
sampling partial flow dilution, which consists of passing the entire dilute exhaust sample through the filters, dilution (section
1.2.1.1, Figures 7 and 11) and sampling system usually form an integral unit. In the case of fractional sampling partial flow
dilution or full flow dilution, which consists of passing through the filters only a portion of the diluted exhaust, the dilution
(section 1.2.1.1, Figures 4, 5, 6, 8, 9, 10 and 12 and section 1.2.1.2, Figure 13) and sampling systems usually form different
units.
In this Directive, the double dilution system DDS (Figure 15) of a full flow dilution system is considered as a specific
modification of a typical particulate sampling system as shown in Figure 14. The double dilution system includes all
important parts of the particulate sampling system, like filter holders and sampling pump, and additionally some dilution
features, like a dilution air supply and a secondary dilution tunnel.
In order to avoid any impact on the control loops, it is recommended that the sample pump be running throughout the
complete test procedure. For the single filter method, a bypass system shall be used for passing the sample through the
sampling filters at the desired times. Interference of the switching procedure on the control loops must be minimized.
Descriptions - Figures 14 and 15
–
PSP particulate sampling probe (Figures 14 and 15)
The particulate sampling probe shown in the figures is the leading section of the particulate transfer tube PTT.
The probe
–
shall be installed facing upstream at a point where the dilution air and exhaust gas are well mixed, i.e. on the
dilution tunnel DT centre-line of the dilution systems (section 1.2.1), approximately 10 tunnel diameters
downstream of the point where the exhaust enters the dilution tunnel),
–
shall be 12 mm in minimum inside diameter,
–
may be heated to no greater than 325 K (52°C) wall temperature by direct heating or by dilution air pre-heating,
provided the air temperature does not exceed 325 K (52°C) prior to the introduction of the exhaust in the dilution
tunnel,
–
may be insulated.
Figure 14
Particulate sampling system
from dilution tunnel DT
PTT
(figures 4 to 13)
FH
optional
FC3
from EGA
or
from PDP
or
from CFV
or
from GFUEL
A sample of the diluted exhaust gas is taken from the dilution tunnel DT of a partial flow or full flow dilution system
through the particulate sampling probe PSP and the particulate transfer tube PTT by means of the sampling pump P. The
sample is passed through the filter holders(s) FH that contain the particulate sampling filters. The sample flow rate is
controlled by the flow controller FC3. If electronic flow compensation EFC (Figure 13) is used, the diluted exhaust gas
flow is used as command signal for FC3.
Figure 15
Dilution system (full flow system only)
FH
FM3
P
SDT
vent
BV
PTT
FC3
from dilution BV optional
PDP
or
CFV
A sample of the diluted exhaust gas is transferred from the dilution tunnel DT of a full flow dilution system through the
particulate sampling probe PSP and the particulate transfer tube PTT to the secondary dilution tunnel SDT, where it is
diluted once more. The sample is then passed through the filter holder(s) FH that contain the particulate sampling filters.
The dilution air flow rate is usually constant whereas the sample flow rate is controlled by the flow controller FC3. If
electronic flow compensation EFC (Figure 13) is used, the total diluted exhaust gas flow is used as command signal
PTT particulate transfer tube (Figures 14 and 15)
The particulate transfer tube must not exceed 1 020 mm in length, and must be minimised in length whenever
possible.
The dimensions are valid for
the partial flow dilution fractional sampling type and the full flow single dilution system from the probe
tip to the filter holder,
the partial flow dilution total sampling type from the end of the dilution tunnel to the filter holder,
the full flow double dilution system from the probe tip to the secondary dilution tunnel.
The transfer tube
may be heated to no greater than 325 K (52°C) wall temperature by direct heating or by dilution air pre-
heating, provided the air temperature does not exceed 325 K (52°C) prior to the introduction of the
exhaust in the dilution tunnel,
may be insulated.
SDT secondary dilution tunnel (Figure 15)
The secondary dilution tunnel should have a minimum diameter of 75 mm and should be sufficient length so as to
provide a residence time of at least 0,25 seconds for the doubly-diluted sample. The primary filter holder, FH,
shall be located within 300 mm of the exit of the SDT.
The secondary dilution tunnel
may be heated to no greater than 325 K (52°C) wall temperature by direct heating or by dilution air pre-
heating, provided the air temperature does not exceed 325 K (52°C) prior to the introduction of the
exhaust in the dilution tunnel,
may be insulated.
FH filter holder(s) (Figures 14 and 15)
For primary and back-up filters one filter housing or separate filter housings may be used. The requirements of
Annex III, Appendix 1, section 1.5.1.3 have to be met.
The filter holder(s)
may be heated to no greater than 325 K (52°C) wall temperature by direct heating or by dilution air pre-
heating, provided the air temperature does not exceed 325 K (52°C),
may be insulated.
P sampling pump (Figures 14 and 15)
The particulate sampling pump shall be located sufficiently distant from the tunnel so that the inlet gas
temperature is maintained constant (± 3 K), if flow correction by FC3 is not used.
DP dilution air pump (Figure 15) (full flow double dilution only)
The dilution air pump shall be located so that the secondary dilution air is supplied at a temperature of 298 K
(25°C) ± 5 K.
FC3 flow controller (Figures 14 and 15)
A flow controller shall be used to compensate the particulate sample flow rate for temperature and backpressure
variations in the sample path, if no other means are available. The flow controller is required if electronic flow
compensation EFC (Figure 13) is used.
FM3 flow measurement device (Figures 14 and 15) (particulate sample flow)
The gas meter or flow instrumentation shall be located sufficiently distant from the sample pump so that the inlet
gas temperature remains constant (± 3 K), if flow correction by FC3 is not used.
FM4 flow measurement device (Figure 15) (dilution air, full flow double dilution only)
The gas meter or flow instrumentation shall be located so that the inlet gas temperature remains at 298 K (25°C)
± 5 K.
BV ball valve (optional)
The ball valve shall have a diameter not less than the inside diameter of the sampling tube and a switching time of
less than 0,5 seconds.
NOTE: If the ambient temperature in the vicinity of PSP, PTT, SDT, and FH is below 239 K (20°C), precautions
should be taken to avoid particle losses onto the cool wall of these parts. Therefore, heating
and/or insulating these parts within the limits given in the respective descriptions is
recommended. It is also recommended that the filter face temperature during sampling be not
below 293 K (20°C).
At high engine loads, the above parts may be cooled by a non-aggressive means such as a circulating fan, as long as the
temperature of the cooling medium is not below 293 K (20°C).
ANNEX III
"Annex XIII
PROVISIONS FOR ENGINES PLACED ON THE MARKET UNDER A "FLEXIBLE SCHEME"
On the request of an equipment manufacturer (OEM), and permission being granted by an approval authority, an engine
manufacturer may during the period between two successive stages of limit values place a limited number of engines on the market
that only comply with the previous stage of emission limit values in accordance with the following provisions
1. ACTIONS BY THE ENGINE MANUFACTURER AND THE OEM
An OEM that wishes to make use of the flexibility scheme shall request permission from any approval authority to purchase
from his engine suppliers, in the period between two emissions stages, the quantities of engines described in sections 1.2 and
1.3, that do not comply with the current emission limit values, but are approved to the nearest previous stage of emission
limits.
The number of engines placed on the market under a flexibility scheme shall, in each engine category, not exceed 20% of the
OEM's annual sales of equipment with engines in that engine category (calculated as the average of the latest 5 years sales on
the EU market). Where an OEM has marketed equipment in the EU for a period of less than 5 years the average will be
calculated based on the period for which the OEM has marketed equipment in the EU.
As an optional alternative option to section 1.2, the OEM may seek permission for his engine suppliers to place on the market
a fixed number of engines under the flexibility scheme. The number of engines in each engine category shall not exceed the
following values
Engine Category
Number of Engines
19-37kW
37-75kW
75-130kW
130-560kW
The OEM shall include in his application to an approval authority the following information
(a)
a sample of the labels to be affixed to each piece of non-road mobile machinery in which an engine placed on the
market under the flexibility scheme will be installed. The labels shall bear the following text: "MACHINE NO …
(sequence of machines) OF … (total number of machines in respective power band) WITH ENGINE No … WITH
TYPE APPROVAL (Dir. 97/68/EC) No …"; and
(b)
a sample of the supplementary label to be affixed on the engine bearing the text referred to in section 2.2 of this
Annex.
The OEM shall notify the approval authorities of each Member State of the use of the flexibility scheme.
The OEM shall provide the approval authority with any information connected with the implementation of the flexibility
scheme that the approval authority may request as necessary for the decision.
The OEM shall file a report every six months to the approval authorities of each Member State on the implementation of the
flexibility schemes he is using. The report shall include cumulative data on the number of engines and NRMM placed on the
market under the flexibility scheme, engine and NRMM serial numbers, and the Member States where the NRMM have been
placed on the market. This procedure shall be continued as long as a flexibility scheme is still in progress.
2. ACTIONS BY THE ENGINE MANUFACTURER
An engine manufacturer may place on the market engines under a flexible scheme covered by an approval in accordance with
Section 1 of this Annex.
The engine manufacturer must put a label on those engines with the following text: "Engine placed on the market under the
flexibility scheme".
3. ACTIONS BY THE APPROVAL AUTHORITY
The approval authority shall evaluate the content of the flexibility scheme request and the enclosed documents. As a
consequence it will inform the OEM of its decision as to whether or not to allow use of the flexibility scheme.
ANNEX IV
The following Annexes shall be added
"Annex XIV
CCNR stage I 1
P N
CO
HC
NOx
PT
(kW)
(g/kWh)
(g/kWh)
(g/k/Wh)
(g/kWh)
37 ≤ P N < 75
6,5
1,3
9,2
0,85
75 ≤ P N < 130
5,0
1,3
9,2
0,70
P ≥ 130
5,0
1,3
n ≥ 2800 tr/min = 9.2
0,54
500 ≤ n < 2800 tr/min = 45 x n (-0.2)
CCNR Protocol 19, Resolution of the Central Commission for the Navigation of the Rhine of 11 May 2000.
Annex XV
CCNR stage II 1
P N
CO
HC
NOx
PT
(kW)
(g/kWh)
(g/kWh)
(g/kWh)
(g/kWh)
18 ≤ P N < 37
5,5
1,5
8,0
0,8
37 ≤ P N < 75
5,0
1,3
7,0
0,4
75 ≤ P N < 130
5,0
1,0
6,0
0,3
130 ≤ P N < 560
3,5
1,0
6,0
0,2
n ≥ 3150 min -1 = 6,0
P N ≥ 560
3,5
1,0
0,2
343 ≤ n < 3150 min -1 = 45 x n (-0,2) –3
n < 343 min -1 = 11,0
CCNR Protocol 21, Resolution of the Central Commission for the Navigation of the Rhine of 31 May 2001."