DMX BASICS:
• DMX is short for “digital multiplexer”, which is a universal protocol designed for the entertainment industry.
It allows control of intelligent fixtures like scanners, moving heads, LED par cans, dimmer packs & effects
machines etc.
• DMX allows you to control many fixture channels, normally up to 512, with varying channels from 0-255 (0-
100%).
• This will give control of channels such as gobo selection, movement, colours, dimming and timing to name
just a few.
• DMX is a very good system, as all this information can be sent down one cable. Used in conjunction with a
DMX controller with memory, all of your channel settings can be saved and recalled easily.
• DMX was designed so that all manufacturers can use the same protocol/language to control their fixtures,
allowing the end user to use any make of fixture from their DMX controller as long as both are DMX
compatible, and the controller has enough channels to control the fixture that is attached.
• Fixtures have an input and output DMX socket, allowing you to connect from the controller to the first
fixture then from that fixture to the next (this is often referred to as “daisy chaining”).
• Sockets are normally 3 pin XLR but can be 5 pin XLR.
DMX fixtures need to have a DMX address set, this is so they can then decode the correct information from
the controller. This is normally done by a digital display panel, where the address can be changed by simple
up and down buttons; the address ranges from 1-512. Alternatively it may be controlled by a row of small
switches, called dip switches; on this type system, the required address is then converted to a binary number.
DMX Connector Wiring
3 Pin wiring is more common, but the 5 pin configuration is often used on larger equipment. With the 5 pin
configuration, not all pins are used, though it is worth checking the fixture manual, as some equipment use
the extra pins for low voltage control. 5 Pin connectors are ideal so there is no confusion over mixer leads and
DMX leads in larger rigs. Sending a mixers 48v phantom power down a DMX cable could damage the DMX
light or fixture.
If making cables, always use suitable DMX cable and do not connect pin 1 GND to the outer casing of the
connector as you might do with audio cables, as this may cause erratic behaviour from your fixture.
Do not make “Y” leads to split cables to fixtures; always use the in and out sockets or a DMX splitter, as again
this may cause erratic behaviour from your fixture.
We recommend you to plug a DMX terminator into any fixture that hasn’t got a DMX lead connected from the
output socket to another fixture; This again is to reduce unexpected behaviour. A DMX terminator is simply a
male XLR plug with 120 ohm, ¼ watt resistor soldered across pin 2 & 3.
3 PIN
5 PIN
PIN 1 GND
PIN 1 GND
PIN 2 -
PIN 2 -
PIN 3 +
PIN 3 +
PIN 4 NOT USED
PIN 5 NOT USED
