CDL Air Brake Air Brake Compressor and Governor 2

Question 1

At what pressure does the safety relief valve typically open to protect the air brake system?

Accepted Answer

150 psi or more

Answer

The safety relief valve opens at 150 psi or more to prevent dangerous over-pressurization if the governor fails.

Question 2

What should you do if the safety relief valve is frequently releasing air during operation?

Accepted Answer

Have the governor and compressor inspected immediately

Answer

Frequent safety valve releases indicate a governor malfunction and require immediate inspection by a qualified mechanic.

Question 3

What must you do before manually draining the air tanks?

Accepted Answer

Bring the vehicle to a complete stop and apply the parking brake

Answer

You must bring the vehicle to a complete stop and apply the parking brake before draining air tanks to ensure safety.

Question 4

Water that accumulates in air tanks can be drained manually using what device?

Accepted Answer

The drain cock or petcock

Answer

A drain cock or petcock at the bottom of each air tank allows manual draining of water that accumulates from compressed air.

Question 5

How often should air tanks be manually drained in cold weather compared to warm weather?

Accepted Answer

More frequently, ideally daily, to prevent moisture from freezing

Answer

In cold weather, tanks should be drained more frequently (ideally daily) to prevent accumulated moisture from freezing and blocking air lines.

CDL Air Brake - Commercial Driver's License Air Brakes Test Practice Test