The decisive advantage of our advanced OHB systems is the availability of very high brake pressures for various safety functions. This brake pressure is generated by an electronically controlled ESP pump, which means higher booster pressure without increasing the size of the booster. Nothing is of greater importance for the control and the possible functions of the OHB system than the sensors. Two sensor types are available:

The Delta-S Sensor

The Hall-effect sensor operates according to the principle of differential displacement measurement. It is used in vacuum brake boosters (tandem design).

The economical OHB system with the Delta-S sensor takes over an important safety function: it supports the braking system if the brake booster fails.

The Double Vacuum Sensor

A powerful sensor that can be used in all booster types, including standard boosters. It operates according to the principle of differential pressure measurement in both booster chambers. An OHB system with a double vacuum sensor offers the following functions:

• Failed booster support
• Cold engine start situation (in a cold start, not enough brake pressure is available due to the insufficient vacuum - in this case, an OHB with a double vacuum sensor makes the conventional vacuum pump superfluous)
• Overboost: extremely increased brake pressure for emergencies