Control Sequence

In an ongoing control operation, the high pass filter (fast filter) is always used to prevent the controlled height from overshooting the nominal value. If a low pass filter (slow filter) were used to calculate the ride height, brief changes of ride height would be consumed. The low-pass filter is used while the vehicle is driven. This type of filtering filters out vibrations which are excited by the road surface.

The high pass filter is used to respond quickly to ride level deviations from setpoint. These take place while the vehicle is stationary in the event of large load changes.

Both sides of the vehicle are controlled individually, i.e. even the setpoint/actual value comparison for both sides is carried out individually. Exception: check for undershooting of the minimum height in Pre-mode and Curb mode: consideration of the left and right mean values in each case.

The following stipulations are applicable here:

• Raising before lowering
• Activation of all valves with control in the same direction
• Individual wheel deactivation

To ensure safe closing of the non-return valve in the air drier, the drain valve is actuated briefly for 200ms after the control operation has ended.

The permissible ON period of the components is monitored while control up operation are executed.