Document ID: chunk:federal_register_of_legislation:F2024L00446:reg:16:p18
Version: federal_register_of_legislation:F2024L00446
Segment Type: reg
Provision Reference: reg 16 (pt 18/108)
Character Range: 933876–936935

belt speed control

              The belt speed shall be controlled with an accuracy of ±0.1 km/h.

              6.5.1.5. Flat belt surface

              The flat belt surface shall be clean, dry and free from foreign material that might cause tyre slippage.

              6.5.1.6. Cooling

              A current of air of variable speed shall be blown towards the vehicle. The set point of the linear velocity of the air at the blower outlet shall be equal to the corresponding dynamometer speed above measurement speeds of 5 km/h. The linear velocity of the air at the blower outlet shall be within ±5 km/h or ±10 per cent of the corresponding measurement speed, whichever is greater.

              6.5.2.  Flat belt measurement

              The measurement procedure may be performed according to either paragraph 6.5.2.2. or paragraph 6.5.2.3. of this annex.

              6.5.2.1. Preconditioning

              The vehicle shall be conditioned on the dynamometer as described in paragraphs 4.2.4.1.1. to 4.2.4.1.3. inclusive of this annex.

              The dynamometer load setting Fd for the preconditioning shall be:

              where in the case of applying paragraph 6.7.2.1:

              ad = 0

              bd = f1a;

              cd = f2a

              or, where in the case of applying paragraph 6.7.2.2.:

              ad = 0

              bd = 0

              The equivalent inertia of the dynamometer shall be the test mass.

              The aerodynamic drag used for the load setting shall be determined in accordance with paragraph 6.7.2. of this annex and may be set directly as input. Otherwise, ad, bd, and cd from this paragraph shall be used.

              At the request of the manufacturer, as an alternative to paragraph 4.2.4.1.2. of this annex, the warm-up may be conducted by driving the vehicle with the flat belt.

              In this case, the warm-up speed shall be 110 per cent of the maximum speed of the applicable WLTC. The warm up is considered complete when the vehicle has been driven for at least 1,200 seconds and the change of measured force over a period of 200 seconds is less than 5 N.

              6.5.2.2. Measurement procedure with stabilised speeds

              6.5.2.2.1. The test shall be conducted from the highest to the lowest reference speed point.

              6.5.2.2.2.  Immediately after the measurement at the previous speed point, the deceleration from the current to the next applicable reference speed point shall be performed in a smooth transition of approximately 1 m/s².

              6.5.2.2.3. The reference speed shall be stabilised for at least 4 seconds and for a maximum of 10 seconds. The measurement equipment shall ensure that the signal of the measured force is stabilised after that period.

              6.5.2.2.4. The force at each reference speed shall be measured for at least 6 seconds while the vehicle speed is kept constant. The resulting force for that reference speed point FjDyno shall be the arithmetic average of the force during