What is a Retarder?


A Retarder is a third independent brake system for recreational vehicles, light, medium, and heavy trucks, and mobile cranes.
A Retarder is an electromagnetic, electro-dynamic eddy current brake.
The term Retarder originates from Latin and means "holds back".


The Retarder works wear-free, it can eliminate 90% of all brake application. Thus the normal foot brake remains cold and is available with emergencies with the full braking power (no fading with hot brake linings). Cost saving, the normal brake linings last up to 8x longer, which decreases the downtime in the shop. Amortization in 1 to 2 years! Downhill higher average speeds can be driven, security and safety is increased, the comfort is improved.



    The Retarder consists of one stator and two rotors. The stator, which is necessary for the structure of the magnetic field, consists of a disk with 8 iron cores on each side, on which the field coils are fastened. This stator is fastened in the frame of the vehicle and interrupts the drive shaft. The rotors are connected on both sides of the stator with the turning drive shaft. By using the 3-6 level control lever switch, which is fastened in the proximity of the steering wheel, the Retarder brakes via the electric or electronic control box which draws current from the batteries and produces a magnetic field. The drive shaft turning rotors are going through the magnetic field and into an opposite rotating magnetic field, alternating polarities, causing a delay. This delay generates eddy currents which slow the rotors and the drive shaft. Braking power is applied  though the Retarder, without using the regular service brakes. Even when the vehicle is in neutral gear, the retarder will slow down the vehicle. The "kinetic" energy is converted into heat and transferred over the cooling fins to the surronding air.

(Wenn Sie mehr über die Wirkungsweise eines Retarder einschließlich grafischer Darstellungen erfahren möchten klicken Sie hier !)

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