Air Brake Manual

Application Line
“T”
13 20
31
Trailer Brake Hand Valve
30
31
The purpose of the trailer brake hand valve (30) is to
allow the driver to control independently the amount
of application air pressure to be directed to the trailer
brakes. It also provides a method of applying the
trailer brakes when coupling the trailer to the tractor.
The valve, also allows the driver to apply the trailer
brakes independently of the tractor. The amount of
application air pressure delivered depends on the
amount the valve is opened by the driver. (It cannot
exceed the reservoir air pressure.) Some valves are
equipped with self returning handles.
39