Document ID: chunk:federal_register_of_legislation:F2024L00446:reg:16:p7
Version: federal_register_of_legislation:F2024L00446
Segment Type: reg
Provision Reference: reg 16 (pt 7/108)
Character Range: 902919–906129

curve determination
              Reference speed points for running resistance determination shall be selected according to paragraph 2.2. of this annex.
              The reference speeds shall be measured in descending order. At the request of the manufacturer, there may be stabilization periods between measurements but the stabilization speed shall not exceed the speed of the next reference speed.
              4.4.2.2. Data collection
              Data sets consisting of actual speed vji actual torque Cji and time over a period of at least 5 seconds shall be measured for every  at a sampling frequency of at least 10 Hz. The data sets collected over one time period for a reference speed vj shall be referred to as one measurement.
              4.4.2.3. Vehicle torque meter measurement procedure
              Prior to the torque meter method test measurement, a vehicle warm-up shall be performed according to paragraph 4.2.4. of this annex.
              During test measurement, steering wheel movement shall be avoided as much as possible, and the vehicle brakes shall not be operated.
              The test shall be repeated until the running resistance data satisfy the measurement precision requirements as specified in paragraph 4.4.3.2. of this annex.
              4.4.2.4. Velocity deviation
              During a measurement at a single reference speed point, the velocity deviation from the arithmetic average velocity (vji-vjm) calculated according to paragraph 4.4.3. of this annex, shall be within the values in Table A4/6.
              Additionally, the arithmetic average velocity vjm at every reference speed point shall not deviate from the reference speed vj by more than ±1 km/h or 2 per cent of the reference speed vj, whichever is greater.
Table A4/6
    Velocity deviation

Time period, s  Velocity deviation, km/h
5 - 10          ±0.2

10 - 15         ±0.4

15 - 20         ±0.6

20 - 25         ±0.8

25 - 30         ±1.0

≥ 30            ±1.2

              4.4.2.5. Atmospheric temperature

              Tests shall be performed under the same temperature conditions as defined in paragraph 4.1.1.2. of this annex.

              4.4.3. Calculation of arithmetic average velocity and arithmetic average torque

              4.4.3.1. Calculation process

              Arithmetic average velocity vjm, km/h, and arithmetic average torque Cjm, in Nm, of each measurement shall be calculated from the data sets collected according to the requirements of paragraph 4.4.2.2. of this annex using the following equations:

               and
           where:
                   is the actual vehicle speed of the ith data set at reference speed point j, km/h;
                  k is the number of data sets in a single measurement;
                   is the actual torque of the ith data set, Nm;
                   is the compensation term for speed drift, Nm, given by the following equation:
              .
                     shall be no greater than 0.05 and may be disregarded if  is not greater than ±0.005 m/s2;
                  mst is the test vehicle mass at the start of the measurements and shall be measured immediately before the warm-up procedure