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Hand brake system
Hand brake is integral with spring
brake actuator on rear axle. Spring
brake chamber piston ram acts
directly on push rod assembly of
brake chamber.
Engine exhaust brake
Exhaust brake operation is coupled
with service brake. Whenever brake
pedal is depressed for applying
brakes, exhaust brake also gets
applied and indicator lamp (E) comes
ON instrument panel.
Stop light switch provides signals both
for rear tail lamps as well as for
exhaust brake solenoid valve.
Solenoid valve opens, allowing
compressed air to flow to exhaust
brake air cylinder, thus operating
exhaust brake butterfly valve.
Since exhaust opening is restricted,
road wheels will drive engine, which
will act as a compressor (resistor),
thus retarding vehicle speed.
Use of engine exhaust brake results
in increased life of brake linings,
brake drums & tyres.
Isolator switch (Exhaust brake)
In certain situations like starting of
vehicle on an upgradient,
simultaneous acceleration and partial
braking of vehicle are required.
Isolator switch can be used to cut off
air supply to exhaust brake air
cylinder, by putting it in off
(disengaged) position. Isolator switch
should be put ON (engaged), as soon
as isolation requirement is over.
3.2 Driving
Driving
Hand brake valve
A.
Brake released
B.
Brake applied
A to B
Gradual application
