Automatic Levelling Devices
What is a levelling device?
A levelling device sets the car headlights level. Older Halogen headlamps use manual levelling devices which are adjusted directly at the headlamp. The adjustment of the low beam has to be completed at every headlamp change or repair. Automatic levelling devices, on the other hand, automatically adjust the beam setting based on load, to ensure the correct setting.
Problems related to poor beam setting
The risk of a bad headlamp adjustment can include:
- dazzling oncoming drivers (1% error in beam setting multiplies dazzling by 20%)
- lack of visibility for the driver (1% error in beam setting reduces lighting efficiency by 20 times at 50 metres)
Automatic levelling devices are required for Xenon lamps
Xenon systems generate such a bright light that even dipped lights can dazzle oncoming drivers. As a result, automatic levelling devices must now be fitted to vehicles with Xenon headlights to ensure that the lights are operating at the correct level, regardless of vehicle load.
Automatic levelling calls for more technology
These regulations call for technological additions such as suspension sensors and electric stepper motors. These devices identify the need for a change as well as physically making the adjustment. All of this is controlled by a lighting ECU.
A headlight’s low beam must be aimed between -0.5% and -2.5%, and current legislation requires 6 different positions (depending on the load of the vehicle).