Document ID: chunk:federal_register_of_legislation:F2024L00446:reg:10:p21
Version: federal_register_of_legislation:F2024L00446
Segment Type: reg
Provision Reference: reg 10 (pt 21/32)
Character Range: 1328486–1331444

not be calculated individually. Instead, depending on the number of completed city cycles before the city cycle when the break-off criterion is reached, the incomplete city cycle shall be combined with previous city cycles and shall be considered as one cycle in the context of the drive trace index calculations.
               If the number of completed city cycles is even, the incomplete city cycle shall be combined with the previous two completed city cycles. See the example in Figure A7/3 below.
Figure A7/3
Example with an even number of completed city test cycles before the city cycle with the break-off criterion

              If the number of completed city cycles is odd, the incomplete city cycle shall be combined with the previous three completed city cycles. See the example in Figure A7/4 below.
              Figure A7/4
Example with an odd number of completed city test cycles before the city cycle with the break-off criterion
              If the number of cycles derived according to Figure A7/3 or Figure A7/4 is less than four, the drive trace indices IWR and RMSSE shall be calculated for each of these cycles and reported.

              If the number of cycles derived according to Figure A7/3 or Figure A7/4 is greater than or equal to four, the drive trace indices IWR and RMSSE shall be calculated for each of these cycles and reported. In this case, the average IWR and the average RMSSE for the combination of any two cycles shall be compared with the respective criteria as specified in paragraph 2.6.8.3.1. of Annex B6 and the IWR of any individual cycle shall not be less than -3.0 or greater than +5.0 per cent.

              8. Calculating n/v ratios
                  n/v ratios shall be calculated using the following equation:

                  where:
              n is engine speed, min-1;
              v is the vehicle speed, km/h;
              ri is the transmission ratio in gear i;
              raxle is the axle transmission ratio.
                  Udyn is the dynamic rolling circumference of the tyres of the drive axle and is calculated using the following equation:

                  where:
                  H/W is the tyre's aspect ratio, e.g. "45" for a 225/45 R17 tyre;
                  W is the tyre width, mm; e.g. "225" for a 225/45 R17 tyre;
                  R is the wheel diameter, inch; e.g. "17" for a 225/45 R17 tyre.
                  Udyn shall be rounded according to paragraph 6.1.8. of this Regulation to whole millimetres.
              If Udyn is different for the front and the rear axles, the value of n/v for the mainly powered axle shall be applied on a dynamometer in both 2WD and 4WD operation mode.
              Upon request, the responsible authority shall be provided with the necessary information for that selection.

Annex B8

Pure electric, hybrid electric and compressed hydrogen fuel cell hybrid vehicles
              1. General requirements
              In