The dimmer is used for the infinitely variable regulation of the output from a light source. Leading edge control is applied to incandescent lamps. Low-voltage halogen lamps with electronic transformer are dimmed using trailing edge technology. Thermal radiators such as tungsten halogen lamps are easy to dim. Fluorescent lamps require special control gear, while compact fluorescent lamps require special electronic control gear units. Conventional compact fluorescent lamps cannot be dimmed. LEDs can easily be dimmed with the appropriate control gear.
In analogue 1V-10V technology, dimming is possible by using a special ECG with input for the 1V-10V control voltage and a potentiometer or a control system supplying analogue 1V-10V control voltage, such as the ERCO Area Net or KNX actuators. The dimmers are often installed in switch cabinets. The control lines are permanently connected to luminaires or groups of luminaires. The digital control protocol, DALI, on the other hand, allows for the individual control of the dimmable ECGs for all the connected luminaires.