Dimmer racks are a specialist device used to control the brightness level of lighting fixtures. Also known as dimmers, these light dimming systems adjust brightness by increasing or decreasing the voltage to the light, affecting how much actual power the lamp receives. By doing this, the light outputâ??s intensity can be adjusted.

Dimmer racks are often used in theatres and concert venues (where they are known as a touring dimmer rack), and specifically controls halogen, resistive incandescent and compact fluorescent lights. For dimming mercury vapor, solid state, fluorescent and other specialist types of lighting, more specialized equipment than a dimmer rack module is needed.

There are several different types of dimmer racks available, starting with the smaller light switch size boxes that are used in homes, all the way up to large consoles which are used in concert venues, theater etc. Such professional dimmer racks are too large to be controlled directly like the ones at home, and so a DMX or DALI control system is used instead.

When dimmer racks used in professional situations, changing the intensity or dimming the lights is known as â??fading upâ? or â??fading downâ?. Itâ??s recommended that lights are not â??fadedâ?? too quickly, as doing so can damage the life expectancy of the lamp in question, although this is less of an issue with more advanced dimmer rack module units.