|
| ||
| Pressure gauge
A pressure gauge mounted on the dashboard shows the available air pressure in the primary reservoir. Some units may be equipped with a gauge that has two needles; one needle indicates primary reservoir pressure and the other shows the secondary reservoir pressure. Low pressure warning device A low pressure warning device is used to visually warn the driver when the pressure within the primary reservoir falls below 414 kPa (60 PSI). The most common type of low pressure warning device is a red lamp mounted on the dash accompanied by a warning buzzer. The dual circuit foot valve (brake pedal) The dual circuit foot valve allows the driver to apply and release both the primary and secondary service brakes at the same time. The foot valve also controls the force applied by the brakes by regulating the amount of air pressure supplied to the brake chambers. Braking force is determined by the force the driver applies to the brake pedal. The brakes are released by removing the force from the brake pedal, causing air pressure in the brake chambers to exhaust to the atmosphere. | ||
The secondary brake circuit is used to apply and release the steering axle service brakes. Units equipped with steering axle brakes that work properly provide the advantage of a shorter stopping distance and greater vehicle stability. | ||
| Page 32 | ||
Alberta.ca > Transportation > Drivers and Vehicles> Driver Guides > Page 32
© 1995 - 2012 Government of Alberta Copyright and Disclaimer