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A quick guide to what you really need to know about DMX512.
- All wiring must be in a continuous run and daisy-chained. No “Tees” are permitted.
- Star wiring is only allowed in conjunction with an opto-splitter.
- Cable shield may be grounded at one end only, preferably at the control console.
- Maximum cable length is 1,800 ft when used for DMX only
- Maximum cable length for systems incorporating RDM is 1000 ft due to timing constraints
- Receiving devices have male connectors, transmitters have female.
- Wire must be Belden 9829, 9842, Cat 5 or equivalent .
- The last DMX device on the line must be terminated with a termination switch or resistor with a value of 100 to 120 ohms between pins 2 and 3.
- RJ45 connectors may be used with Cat5 cable, for permanent wiring.
- Cat5 UTP cable may be used inside metal conduit. Use Cat5 STP when installed in raceways.
DMX XLR Wiring Connections Wire color is manufacturer specific. Use connector to determine pin number for each wire.
| XLR Pin | Standard RS422/485 Wire
| | 1 | Shield/Common | | 2 | Data - (pair 1 complement)
| | 3 | Data + (pair 1 true)
| 4
| Optional Data - | 5
| Optional Data +
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DMX Wiring Connections for Cat 5 or equivalent wire This chart is based on the E1.27-2 standard for DMX cabling and is not intended for DMX-over-Ethernet wiring. Wire Color and #
| Function
| Equivalent XLR Pin #
| 1 White/Orange
| Data + (pair 1 true)
| 3 | 2 Orange
| Data - (pair 1 complement)
| 2
| 3 White/Green
| Optional Data + (pair 2)
| 5
| 6
Green
| Optional Data - (pair 2)
| 4
| 4 Blue
| Unassigned
| -
| 5 White/Blue
| Unassigned | -
| 7 White/Brown
| Common for pair 1
| 1 | 8 Brown
| Common for pair 2
| 1 |
Wires 4 and 5 are commonly used in non-DMX equipment to carry power-over-Ethernet. Best practice for DMX only wiring installers is to cap and turn back this pair to avoid accidental damage to equipment. We strongly recommend wires 7 and 8 be connected even if the optional data wires aren't used. The use of RJ45 connectors for DMX equipment should only be done with caution, and should be restricted to pathc bays in access controlled rooms. RJ45 connectors and Cat5 cable should not be used to connect portable equipment.
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