Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:99:p24
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 99 (pt 24/39)
Character Range: 1220272–1223364

vehicle if either the PEMS test in dual-fuel mode or the PEMS test in Diesel mode has concluded a fail.

              10. Additional test procedures

10.1. Additional emission test procedure requirements for dual-fuel engines
              10.1.1.  Dual-fuel engines shall comply with the requirements of Appendix 4 in addition to the requirements of this Regulation (incl. Annex 4) when performing an emission test.

10.2. Additional PEMS emission test procedure requirements for dual-fuel engines
              10.2.1. When subject to a PEMS test, dual-fuel engines shall comply with the requirements of Appendix 5 in addition to the other PEMS requirements of this Regulation.

              10.2.2.  Torque correction

              When necessary, for instance because of variation of the gas fuel composition, the manufacturer may decide to correct the ECU torque signal. In that case the following requirements shall apply.

       10.2.2.1. Correction of the PEMS torque signal

              The manufacturer shall submit to the Type Approval Authority a description of the relationship permitting to extrapolate the real torque from the torques obtained during emission testing with the 2 appropriate reference fuels and from the actually retrievable torque in the ECU.

              10.2.2.1.1. In the case when the torques obtained with the two reference fuels may be considered of the same magnitude (that is within the 7 per cent considered in paragraph 9.4.2.5. of this Regulation), the use of the corrected ECU value is not necessary,

       10.2.2.2. Torque value to consider in a PEMS test

              For PEMS test (work based window) the corrected torque value shall result from that interpolation

       10.2.2.3. Conformity of the ECU torque-signal

              The "Maximum torque" method specified in Appendix 4 to Annex 8 shall be understood as demonstrating that a point between the reference maximum torque curves obtained at a certain engine speed when testing with the 2 applicable reference fuels has been reached during vehicle testing.

              The value of that point shall be estimated with the agreement of the Type Approval Authority on the basis of the actual fuel composition sampled as close as possible to the engine and the power curves obtained with each of the reference fuels during the emission certification test.

       10.3. Additional dual-fuel specific CO2 determination provisions

              Section 3.1. of Annex 12 regarding the determination of CO2 emissions in case of raw measurement is not applicable to dual-fuel engines. Instead the following provisions shall apply:

              The measured test-averaged fuel consumption according to section 4.3. of Annex 12 shall be used as the base for calculating the test averaged CO2 emissions.

              The mass of each fuel consumed shall be used to determine, according to section A.6.4. of this annex, the molar hydrogen ratio and the mass fractions of the fuel mix in the test.

              The total fuel mass shall be determined according to equations 23