GF43.30-W-3002A | Braking torque limitation, function |
MODEL 375.4, 944, 950, 952, 953, 954 with CODE (BA9) Voith R115 secondary retarder
During a brake application the deceleration energy is converted into thermal energy.
In order to prevent the maximum coolant and oil temperature which is specified in the retarder control unit from being exceeded and to exploit the cooling capacity of the engine cooling system to the maximum, the retarder braking torque is reduced accordingly as a protection of the engine cooling system and of the retarder. The actuating pressure is limited.
To do this, the retarder control unit is supplied continuously with information from the temperature sensors regarding the coolant temperature and oil temperature.
The retarder braking torque is reduced in the case of:
excessively high coolant temperature,
excessively high retarder oil temperature,
excessive rise in the retarder oil temperature.
As soon as the braking torque is limited, a message with information about why this occurred is relayed onto the vehicle CAN bus.
Each measure is evaluated individually in the retarder control unit and a so-called adaptation factor is determined. The maximum factor of all the measures determines the limit, through to the retarder being switched off completely.