F1ANNEX XIIInertia dynamometer test method for brake linings
3.TEST CONDITIONS
3.1.
The dynamometer shall be set as close as possible, with ± 5 % tolerance, to the rotary inertia equivalent to that part of the total inertia of the vehicle braked by the appropriate wheel(s) according to the following formula:
where:
- I
rotary inertia (kgm2)
- R
dynamic tyre rolling radius(m)
- M
that part of the maximum mass of the vehicle braked by the appropriate wheel(s).
In the case of a single-ended dynamometer, this part shall be calculated from the design braking distribution in the case of motor vehicles when deceleration corresponds to the appropriate value given in point 2.1.1.1.1 of Annex II; in the case of trailers, the value of M shall correspond to the load on the ground for the appropriate wheel when the vehicle is stationary and loaded to its maximum mass.
3.2.
The initial rotational speed of the inertia dynamometer shall correspond to the linear speed of the vehicle as prescribed in Annex II and shall be based on the rolling radius of the tyre;
3.3.
Brake linings shall be at least 80 % bedded and shall not have exceeded a temperature of 180 °C during the bedding procedure, or alternatively, at the vehicle manufacturer's request, be bedded in accordance with his recommendations.
3.4.
Cooling air may be used, flowing over the brake in a direction perpendicular to its axis of rotation. The velocity of the cooling air flowing over the brake shall not be greater than 10 km/h. The temperature of the cooling air shall be the ambient temperature.
Substituted by Commission Directive 98/12/EC of 27 January 1998 adapting to technical progress Council Directive 71/320/EEC on the approximation of the laws of the Member States relating to the braking devices of certain categories of motor vehicles and their trailers (Text with EEA relevance).