Delaware CDL DMV Air Brakes 1

The total stopping distance for vehicles equipped with air brakes is made up of four factors: perception distance, reaction distance, brake lag distance, and braking distance. When braking at a speed of 55 mph while driving on dry pavement, the brake lag can add around 32 feet to the vehicle's total stopping distance.

Before driving a vehicle with a dual air system, allow time for the air compressor to build up a minimum pressure of 100 psi in both the primary and secondary systems.

The purpose of an Anti-Lock Braking System (ABS) is to prevent a vehicle's wheels from locking up when the driver brakes hard on a slippery surface.

When performing a static leakage test on a double combination vehicle with air brakes, the leakage rate should be no more than 3 psi in one minute. If the air leaks from the air brake system at a quicker rate, the vehicle should not be driven because something likely needs to be repaired.

Vehicles with air brakes are required to be equipped with a low pressure warning device. A wig wag is a type of low air pressure warning device. This device drops a mechanical arm into the driver's view if the pressure in the tanks drops to a level between 55 and 75 psi.

Truck tractors with air brakes built on or after March 1, 1997, and other vehicles with air brakes built on or after March 1, 1998, must be equipped with anti-lock brakes.

Truck tractors with air brakes built on or after March 1, 1997 must be equipped with Anti-Lock Braking Systems (ABS).

Because air pressure can eventually leak away, the emergency brakes in an air brake system must be held on by mechanical force.

On long and/or steep downgrades, you should primarily use engine braking to control the speed of your vehicle. Use your brakes only as a supplement to this effect.

The stab braking method for emergency stops involves fully applying the brakes until they lock up. The brakes are then released until the wheels start rolling, then the process is repeated.

In a vehicle with dual parking control valves, there is a separate air tank that can be used to temporarily release the spring brakes if they have been activated due to low air pressure. Pushing in the proper control will release the spring brakes for a short period of time, allowing the driver to move the vehicle in an emergency.

Brakes heat up with use. If they are overused and become too hot, expansion and chemical changes will make them less effective and eventually cause them to stop working altogether. This is known as "brake fade."

In a vehicle with air brakes, the brake lights are activated when the brake pedal is pushed and air pressure moves an electric switch. With the application of air pressure, the switch will then turn on the brake lights.

Air brakes are really three different braking systems: the service brake, the parking brake, and the emergency brake. Emergency and parking brakes are applied with mechanical force.

An air compressor governor will stop the compressor from pumping air once the air tanks are at an air pressure level of 125 psi. This air pressure level is referred to as the "cut-out" level.

Vehicles with Anti-Lock Braking Systems (ABS) have yellow malfunction lamps.

Before driving, you should always verify that your service brakes are in good working order. Testing the brakes before a trip allows you to locate any problems before you need to brake while on the road.

It is essential that your low pressure warning light functions properly. After allowing the system to charge, you can test the warning signal by rapidly applying and releasing the brake pedal. This will release air from the braking system and the warning signal should come on when pressure drops to a dangerous level.

A one-way check valve is required to be between an air compressor and the first main reservoir. This valve prevents air from escaping the system if the air compressor develops a leak.

Friction inside a brake drum is caused when the brake shoes and linings push against the inside of the drum. The friction in the drums will slow and stop the vehicle.

A modulating control valve allows a driver to gradually apply spring brakes. In equipped vehicles, the valve is controlled by a lever located on the dashboard.

Pressing and releasing the brake pedal unnecessarily can let air out faster than the compressor can replace it, reducing the available air pressure. If the air pressure in an air brake system gets too low, the brakes will no longer work.

Compressed air in an air brake system usually contains a certain amount of water and compressor oil. The water and oil can damage the brakes if left to accumulate in the system. Tanks must be drained regularly to remove this build-up.

Because air takes time to flow through the air lines to the brakes, air brakes cannot begin working instantly. There is often a brake lag of at least one-half of a second between the moment the brake pedal is pressed and the moment the brakes begin to work.

In an air brake system, the air compressor pumps air into the air storage tanks. The air compressor is controlled by the air compressor governor.