Document ID: chunk:federal_register_of_legislation:F2006L03061:body:0:p15
Version: federal_register_of_legislation:F2006L03061
Segment Type: other
Provision Reference: 
Character Range: 41928–44857

I is the dynamometer inertia, in kg.m2

M is the mass supported by the wheel at the 'GALR' in kg.

R is the 'Static Loaded Tyre Radius' of the tyre, as specified by the tyre manufacturer, in metres.

The ambient temperature shall be between 23.0 and 38.0° C.

38.3.8.2.                    Ambient air shall be directed continuously over the brake drum or disc at a velocity of not more than 11.2 m/s.

38.3.8.3.                    The temperature of each brake shall be measured by a single plug-type thermocouple installed in the centre of the lining surface of the most heavily loaded shoe or pad. The thermocouple shall be outside any centre groove.

38.3.8.4.                    The rate of brake drum or disc rotation on a  dynamometer corresponding to the rate of rotation on a vehicle at a given speed shall be calculated by assuming a tyre radius equal to the 'Static Loaded Tyre Radius' specified by the tyre manufacturer.

38.3.8.5.                    Burnishing, if conducted, shall consist of:

            (1) not more than 200 stops such that any instantaneous deceleration does not exceed 3.1 m/s2 from a maximum speed of 65 km/h. The initial brake temperature for each stop shall be not less than 155 and not more than 200° C;

            and

            (2)  not more than 200 additional stops from a maximum speed of 65 km/h at a deceleration not exceeding 3.1 m/s2. The initial brake temperature for each stop shall not be less than 230 and not more than 290° C.

After burnishing, the 'Brakes' will be adjusted in accordance with the 'Manufacturer's' recommendations.

38.3.8.6.                    Brake temperature shall be increased to the specified level by conducting one or more stops from not more than 65 km/h at a deceleration not exceeding 3.1 m/s2, or decreased to a specified level by rotating the drum or disc at a constant speed not exceeding 50 km/h.

38.3.8.7.                    Speeds, decelerations and time specified in clause 38.3.8 shall be achieved within the following tolerance limits:

Speeds: +5, -1 km/h

Decelerations: +0.25, -0.25 m/s2

Times:   +5, -5 seconds.

38.3.9.                          Service Brake Effectiveness - Dynamometer Test

38.3.9.1.                    The service brake effectiveness test is to be conducted with an initial brake temperature of between 50 and 95°C by conducting a series of stops from 80 km/h whilst maintaining constant brake actuator air pressure.               The average torque from the time the specified air pressure is reached until the brake stops is divided by the 'Static Loaded Tyre Radius' specified by the tyre manufacturer to determine the retardation force. The complete test procedure requires seven stops to be made, each from the specified initial temperature, with the first run pressure being 138 kPa and increasing an additional 69 kPa for each of the remaining stops.

38.3.9.2.                    If a