DMX System Design — Universes, Wiring & Fixtures
Controlling color, motion, and drama in architectural and entertainment lighting.
DMX512 Basics
512 channels per universe. Each universe carries data for up to 512 parameters. An RGBW fixture uses 4 channels. So one universe controls up to 128 RGBW fixtures. Use DMX splitters (not splices) to branch the signal. Always terminate the last device on each run.
DMX Channel Allocation
| fixture type | channels | per universe |
|---|---|---|
| RGB wash light | 3 (R/G/B) | 170 fixtures |
| RGBW wash light | 4 (R/G/B/W) | 128 fixtures |
| RGBW + dimmer | 5 | 102 fixtures |
| Moving head (basic) | 16–24 | 21–32 fixtures |
| Pixel strip (per pixel) | 3 per pixel | 170 pixels |
Wiring & Signal Distribution
DMX uses a daisy-chain topology with shielded cable (5-pin XLR or Cat5e for architectural). Maximum run length: 300m from controller to last fixture. Use DMX splitters/boosters for branches — never split with Y-cables. Terminate the last fixture with a 120Ω resistor across pins 2-3.
Art-Net & sACN
For large installations (facades, stadiums), Art-Net or sACN sends multiple DMX universes over Ethernet. One Ethernet port can carry hundreds of universes. This eliminates long DMX cable runs and simplifies infrastructure. Use managed network switches for reliable distribution.