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Function Description
Voith Turbo I Aftersales Service Manual Voith Retarder VR 115 E I Design and Function
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Function Description
Non-return valve (inlet) (1900)
When the retarder is switched on, the oil sump is
pressurized. This opens the non-return valve (inlet)
(1900) and allows oil into the working space.
Non-return valve (outlet) (2100)
In braking mode, the oil reaches the heat exchanger
from the working space via the non-return valve
(outlet) (2100), is cooled down and is fed back into the
system circuit.
Pressure control valve (2200)
In no-load operation of the retarder, the pressure
control valve (2200) regulates the lubrication.
Casing ventilation (2300)
At the beginning of the braking process, the oil expels
the air located in the system circuit from the retarder
via the casing ventilation (2300) and a de-aeration
filter (2810).
Once the system circuit is free of air, a float will rise
and seal the casing ventilation.
Proportional valve (3700)
Depending on the intensity of the electric input signal,
the proportional valve (3700) issues a pneumatic
constant-air pressure which acts on the oil tank of the
retarder.
Oil temperature sensor (5200/1) and
coolant (5200/2)
The temperature sensors are screwed into the cooling
system of the vehicle (return pipe from retarder to heat
exchanger) and in the oil duct of the retarder. The
temperature sensors pass on information on the
temperature of the coolant and oil to the controller.
Maximum values for the temperature of coolant and
oil are set in the controller for protection of the cooling
system and the retarder. To prevent the values being
exceeded, the controller adapts the braking torque of
the retarder accordingly via the constant-air
pressure p
y
.
The braking torque and the heat produced regulate
themselves until an equilibrium has been reached
between the braking force and the heat dissipated via
the vehicle cooling system.
If the temperature limit is exceeded during braking,
the braking torque is adapted to protect the cooling
system and retarder.
If the critical temperature threshold has been
exceeded, the braking torque is no longer active.
The controller also adjusts the braking torque if the
temperature of the oil increases rapidly, regardless of
the actual temperature of the oil.
During temperature adaptation or failure of the
retarder, you must use the service brake to slow down
the vehicle.
Pressure sensor (9000)
The pressure sensor (9000) measures the pneumatic
constant-air pressure. A deviation from the allowed
pressure tolerance is recognized as a fault and
displayed by the controller.
