ETC Test. During a prescribed transient cycle of warmed-up engine operating conditions, which is based closely on road-type-specific driving patterns of heavy-duty engines installed in trucks and buses, the above pollutants shall be examined either after diluting the total exhaust gas with conditioned ambient air (CVS system with double dilution for particulates) or by determining the gaseous components in the raw exhaust gas and the particulates with a partial flow dilution system. Using the engine torque and speed feedback signals of the engine dynamometer, the power shall be integrated with respect to time of the cycle resulting in the work produced by the engine over the cycle. For a CVS system, the concentration of NOx and HC shall be determined over the cycle by integration of the analyzer signal, whereas the concentration of CO, CO2, and NMHC may be determined by integration of the analyzer signal or by bag sampling. If measured in the raw exhaust gas, all gaseous components shall be determined over the cycle by integration of the analyzer signal. For particulates, a proportional sample shall be collected on a suitable filter. The raw or diluted 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 get the grams of each pollutant emitted per kilowatt hour, as described in Appendix 2 to this annex.
Appears in 3 contracts
Sources: Agreement Concerning the Adoption of Uniform Technical Prescriptions for Wheeled Vehicles, Agreement Concerning the Adoption of Uniform Technical Prescriptions for Wheeled Vehicles, Agreement Concerning the Adoption of Uniform Technical Prescriptions for Wheeled Vehicles