This standard specifies the limits and measurement methods for emissions from diesel vehicles under free acceleration and lugdown cycle as well as the methods and judgment bases for appearance inspection and OBD inspection of diesel vehicles.
This standard is applicable to the inspection for new produced diesel vehicle at end of production line, inspection for register vehicle, and inspection for in-use vehicle, and it is also applicable to other vehicles equipped with compression ignition engine. This standard is not applicable to low speed trucks and three-wheeled vehicles.
2 Normative references
The following standards contain provisions which, through reference in this text, constitute provisions of this standard. For undated references, the valid versions shall apply.
GB/T 5181-2001 Automotive emission - Terms and definitions
GB 7258 Technical specifications for safety of power-driven vehicles operating on roads
GB 17691 Limits and measurement methods for exhaust pollutants from compression ignition and gas fueled positive ignition engines of vehicles
GB 17691-2018 Limits and measurement methods for emissions from diesel fueled heavy-duty vehicles (China VI)
GB/T 17692 Measurement methods of net power for automotive engines
GB 18352 Limits and measurement methods for emissions from light-duty vehicles
GB 19147 Automobile diesel fuels
HJ 437 Technical specification for on-board diagnostic (OBD) system of compression ignition and gas fueled positive ignition engines of vehicles
HJ 845-2017 Measurement method and specifications for exhaust pollutants from in-use diesel vehicles by remote sensing method
3 Terms and definitions
For the purpose of this standard, the following terms and definitions apply.
3.1
net power
net power of engine measured according to GB/T 17692
3.2
compression ignition engine
engine operating according to compression ignition principle (e.g., diesel engine)
3.3
opacity meter
instrument used for continuous measurement of optical absorption coefficient of exhaust gas, as specified in Appendix C
3.4
maximum rated engine speed
the maximum full-load speed allowed by the diesel engine
3.5
minimum rated engine speed
——the maximum of the followings: 45% of the maximum rated engine speed; 1000r/min; the minimum idle speed; or
——lower speed required by the manufacturer
3.6
wheel power
actually measured output power of the drive wheel when the vehicle is operating on the chassis dynamometer
3.7
maximum wheel power, MaxHP
the maximum wheel power measured using the method specified in this standard
3.8
optical absorption coefficient, k
coefficient indicating the attenuation of light beam by smoke exhaust per unit length, which is the product of the number (n) of particles per unit volume, the mean projected area (a) of particles and the extinction coefficient (Q) of particles
