1 Scope
This standard specifies emission limit and measurement method and technical requirements and testing method for on-board diagnostics (OBD) system of gasoline engines for heavy-duty vehicles and automotive vehicles.
This standard is applicable to type approval, manufacture conformity inspection and vehicle-engine compliance inspection of gasoline engine for motor vehicle of category M2, M3, N2 and N3 and M1 having a gross mass larger than 3500 kg, whose design vehicle speed is larger than 25 km/h, as well as vehicles equipped with them.
If category M2 vehicles equipped with gasoline engine have been applied with type approval according to the requirements of GB 18352.3-2005, the engines for the vehicles of such category may not be typed approved according to this Standard.
2 Normative References
The following standards contain provisions which, through reference in this text, constitute provisions of this standard. For undated references, the latest edition of the normative document referred to applies.
GB/T 15089-2001 Classification of power-driven vehicles and trailers
GB/T 17692-1999 Measurement methods of net power for automotive engines
GB 17930 Unleaded petrol (gasoline) for motor vehicles
GB 18285-2005 Limits and measurement methods for exhaust pollutants from vehicles equipped ignition engine under two-speed idle conditions and simple driving mode conditions
GB 18352.3-2005 Limits and measurement methods for emissions from light-duty vehicles (Ⅲ, IV China)
GB 20890-2007 Test Procedures and Requirement of Durability of Emission Control Systems for Heavy-duty Vehicles
ISO 16183 Heavy duty engines -- Measurement of gaseous emissions from raw exhaust gas and of particulate emissions using partial flow dilution systems under transient test conditions
ISO 16185 Road vehicles -- Engine families for certification of heavy-duty vehicles by Exhaust emission
3 Terms and Definitions
For the purposes of this standard, the following terms and definitions apply.
3.1 gaseous pollutant
Carbon monoxide (CO), hydrocarbon (HC), (assuming C-H ratio for gasoline engine as C1H1.85 ) and nitric oxides (NOx, expressed in NO2 equivalent)
3.2 test cycle
Program of test that the engine is tested at the required rotation rate and torsion moment runs in transient state working condition
3.3 type approval of engine (or engine series)
Approval of engine (or engine series) type by exhaust pollutant emission level
3.4 gasoline engine
Gasoline-fueled positive ignition (P.I.) engine
3.5 engine type
Engine of same category without difference in basic characteristics, listed in Appendix A
3.6 engine series
A group of engines designed by the manufacturer according to Appendix AB, which has similar exhaust emission characteristic; all engines in same series shall satisfy corresponding emission limits
3.7 source engine
The engine, selected from a engine series, which can reflect emission characteristics of this engine series in behalf
3.8 net power
The power measured at engine crankshaft end point or equivalent component by the power measurement method specified in GB/T 17692-1999 on the bedstand
3.9 maximum net power (Pmax)
The maximum net power applied in the type approval application by the manufacturer
3.10 load percentage
The maximum torsion percentage accomplished by an engine at a certain rotation rate
3.11 transient state cycle of heavy-duty gasoline engine
1830 test cycles stated in Article 7.2 of this Standard, which change working condition by second. This test cycle is to adopt the hormalized rotation rate - time and torsion moment - time date of the engines listed in Appendix BB, and convert them to the actual rotation rate - time and torsion moment - time series of the test engine by the method specified in Appendix BA
3.12 working speed range of engine
Most common engine speed range of the engine in actual work specified in Appendix B of this Standard, which ranges between maximum net-power rotation rate and idling rotation rate
3.13 maximum net-power rotation rate (nPmax)
Rotation rate of the engine when it gives the maximum net power
