What is a Dimmer Pack?

A dimmer pack is a portable unit that controls how much power reaches conventional stage lights, letting a lighting desk set their brightness over DMX. Each pack has several channels, typically four to twelve, and each channel dims one light or a small group.

How a dimmer pack works

A dimmer pack sits between the power supply and the lights:

  1. Power in: the pack is connected to a suitable power supply, often a three-phase outlet for larger packs.
  2. Lights out: conventional fixtures, such as PARs, profiles and fresnels with tungsten lamps, plug into its channels.
  3. Control: the lighting desk sends DMX signals to the pack, telling each channel what level to output.
  4. Dimming: the pack varies the power to each channel, so the lamp brightens or fades smoothly.

A lighting engineer plans which lights go on which channels using the light plot. Venues often list their dimmer and power details in the technical specification sent to visiting shows, and many share those documents through Crescat.

Dimmer pack vs LED fixtures

Dimmer packs are needed for conventional lamps, which dim when their power is reduced. Most LED and moving lights take constant power and dim internally, controlled directly by DMX. Plugging them into a dimmed channel can damage them, so they go on a non-dim or relay channel instead.

What to check before using a dimmer pack

  • Number of channels against the lights in the plan
  • Maximum load per channel and for the whole pack
  • Available power supply and connectors
  • DMX start address set to match the desk
  • Non-dim mode for LEDs, moving lights and haze machines

Frequently asked questions

Can you plug LED lights into a dimmer pack?

Not into a dimmed channel, unless the fixture is specifically designed for it. Most LED fixtures need constant power and are dimmed by DMX. Set the channel to non-dim or use a separate power distribution unit.

What is DMX?

DMX is the standard control signal for stage lighting. A lighting desk sends it down a cable to dimmers and fixtures, and each device responds to its own channel numbers, called its address.

How many lights can go on one dimmer channel?

As many as the channel's power rating allows. Add up the wattage of the lamps and keep the total within the channel's rated load, leaving some headroom.

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