Arizona Air Brakes CDL Practice Test

What is the function of the governor in an air brake system?

1. It monitors the air tank pressure

2. It opens the safety valve

3. It acts as a compressor

4. It applies the service brakes

The correct answer is: It monitors the air tank pressure

The governor in an air brake system plays a crucial role in monitoring and regulating the air pressure within the system. Its primary function is to maintain the air supply at optimal levels, ensuring that the brakes operate effectively when needed. This involves controlling when the air compressor should be turned on or off based on the pressure in the air tanks. When the air pressure in the tanks reaches a specific threshold, the governor signals the compressor to stop running, preventing over-pressurization and potential damage to the system. Conversely, if the pressure drops below a designated level, the governor will activate the compressor to build the pressure back up. This function is essential for the safe and reliable operation of air brakes, as the brakes require a sufficient amount of air pressure to engage effectively. By monitoring the air tank pressure, the governor helps to ensure that the braking system is always ready for use.