Abstract: A regulating device is for a primary braking system in the drive train of a vehicle, especially a primary retarder in a vehicle. The device includes at least one control/regulator unit, a device for detecting gear shifts transmitting at least one measuring signal, and at least one actuator enabling the braking moment of the primary braking system to be adjusted. The regulating device is characterized in that the at least one control/regulator unit controls the at least one actuator in order to adjust the braking moment of the primary braking system according to the measuring signal or measuring signals in such a way that the braking moment of the primary brake is reduced for the entire duration of a gear shift.

Abstract: A system for regulating a retarder, in particular a primary retarder in a vehicle, includes at least one control-regulator unit, a device for picking up measuring signals in order to detect gear speed settings, and at least one actuator for setting the retarder braking movement. The regulating system is characterized in that, on the basis of the measuring signals for detecting gear changes, the at least one control-regulator unit controls the at least one actuator for setting the retarder braking moment, such that the braking moment of the retarder does not exceed the maximum permissible braking moment (M.sub.maxR or M.sub.maxHA) for a given driving speed.