DMX is a digital lighting control protocol, in which instead of 1 core for each channel used & a common gorund (like on the Lighting Desk), 512 channels of control are transmitted down 3 wires: Data+, Data-, Gnd, with ground usually being the sheild or braid, Data+ & Data- are a twisted pair.
Current supported devices
If you're taking out equipment with different pin numbers, remember to take some conversion cables.
YSTV runs 2 lines (one each way)down a single Cat5e cable, from the control room's Master patch panel, to the LX patch panel in the studio. Currently unused.
These are on 3 or 5 pin XLR.
DO NOT plug dmx into any sound gear - something will be unhappy!
- DMX requires a cable impedance of 120ohms.
- try not to use mic cable, however it will suffice for short runs (<40m)
- Equipment is "daisy chained" together, using each device's input and an output ports.
- Data+ and Data- must be a twisted pair.
- Multiple types of cable will do the job:
Sheilded Twisted pair:
- This is the "defacto-standard"
- You can get it almost anywhere, below are some retailers (no links because they inevitably die! - just go googling)
- Usedlighting / stagelighting (lighting Partners Ltd)
- Impedance of 110 ohms (approx) makes it suitable.
- Use any twister pair, and pick another as ground.
- Don't run DMX right next to audio cables of any kind unless completely unavoidable, even if everything is balanced. You may hear the DMX data - The sync pulses manifest as an intermittent clicks...