Document ID: chunk:federal_register_of_legislation:F2023C00229:reg:4:p27
Version: federal_register_of_legislation:F2023C00229
Segment Type: reg
Provision Reference: reg 4 (pt 27/42)
Character Range: 77705–80331

engine may be tested on a third fuel (fuel 3) if the λ-shift factor (Sλ) lies between 0,89 (i.e. the lower range of GR) and 1,19 (i.e. the upper range of G25) for example when fuel 3 is a market fuel. The results of this test may be used as a basis for the evaluation of the conformity of the production.

4.1.3.                        In the case of an engine fuelled with natural gas which is self-adaptive for the range of H-gases on the one hand and the range of L-gases on the other hand, and which switches between the H-range and the L-range by means of a switch, the parent engine shall be tested on the relevant reference fuel as specified in Annex IV for each range, at each position of the switch. The fuels are GR (fuel 1) and G23 (fuel 3) for the H-range of gases and G25 (fuel 2) and G23 (fuel 3) for the L-range of gases. The parent engine shall meet the requirements of this Directive at both positions of the switch without any readjustment to the fuelling between the two tests at each position of the switch. However, one adaptation run over one ETC cycle without measurement is permitted after the change of the fuel. Before testing the parent engine shall be run-in using the procedure given in paragraph 3 of Appendix 2 to Annex III.

4.1.3.1.                    At the manufacturer's request the engine may be tested on a third fuel instead of G23 (fuel 3) if the λ-shift factor (Sλ) lies between 0,89 (i.e. the lower range of GR) and 1,19 (i.e. the upper range of G25), for example when fuel 3 is a market fuel. The results of this test may be used as a basis for the evaluation of the conformity of the production.

4.1.4.                        In the case of natural gas engines, the ratio of the emission results 'r' shall be determined for each pollutant as follows:

         or,

              and,

4.1.5.                        In the case of LPG the parent engine should demonstrate its capability to adapt to any fuel composition that may occur across the market. In the case of LPG there are variations in C3/C4 composition. These variations are reflected in the reference fuels. The parent engine should meet the emission requirements on the reference fuels A and B as specified in Annex IV without any readjustment to the fuelling between the two tests. However, one adaptation run over one ETC cycle without measurement is permitted after the change of the fuel. Before testing, the parent engine shall be run-in using the procedure defined in paragraph 3 of Appendix 2 to Annex III.

               4.1.5.1.                    The ratio of emission results 'r' shall be determined for