# DMX wiring



## ship (Apr 4, 2009)

I know the Backstage handbook says for XLR cable white on pin two and black for pin three. One would assume that's going to be the same for DMX cable but it constantly amazes me how it's not the case in no standard.

How do you wire or see your DMX cable? Black or blue to pin three or pin two?


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## porkchop (Apr 4, 2009)

The cable we buy is a black insulated wire, a white insulated wire, and loose wire that winds around both of those insulated wires for the ground pin. Personally I hate it, I think that it makes our cable more prone to poor grounding and that we should buy cable with 3 individually insulated wires. None the less our consistent wiring is loose wire to pin one, white to pin two, and black to pin three. Anyone else have this loose wire in their cables?


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## David Ashton (Apr 4, 2009)

We all have this "loose" wire, it's the screening wire and if you just used 3 core you would have no screen and get interference, it is not a ground wire and should not ever be connected to the shell of the xlr as this will give ground loop problems as in audio but you will see the problems, not hear them.


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## derekleffew (Apr 4, 2009)

1-shield
2-white
3-black
4-red
5-green


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## ship (Apr 6, 2009)

porkchop said:


> The cable we buy is a black insulated wire, a white insulated wire, and loose wire that winds around both of those insulated wires for the ground pin. Personally I hate it, I think that it makes our cable more prone to poor grounding and that we should buy cable with 3 individually insulated wires. None the less our consistent wiring is loose wire to pin one, white to pin two, and black to pin three. Anyone else have this loose wire in their cables?



That cable you get in your data lines is called shielded or insulated cable with pin 1 going to the drain or index wire on the plug. Sounds proper to me in if it were not there, you would get a lot of interference onto the drain or index return for the data before or after talking with your computer chips for interference. Only "un-shielded" microphone cable and some LED light fixtures don't need an insulated braided or foil or both shield over the data lines in preventing other magnetic fields about the system from interfering with the data line pin 2&3 communication.

White to pin 2 and black to pin three with this hopefull insulalted "ground" though it isn't really one insulated within the plug from touching either of them, is similar to what I observe in some kind of black or blue to pin three. Not a ground, index and shield for the other conductors. Hope it helps in not confounding them but in understanding what it's purpose is.


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## ship (Apr 6, 2009)

Hmm, Red, Green... seen that and what I use but seen it in reverse also.


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## derekleffew (Apr 7, 2009)

ship said:


> Hmm, Red, Green... seen that and what I use but seen it in reverse also.


I guess the moral of the story is CHECK BOTH ENDS, and never assume, even/especially with 2 conductor + ground AC cables. The wires don't care what color they are, but standards exist for a reason.


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## Mayhem (Apr 14, 2009)

ship said:


> …"un-shielded" microphone cable…



Surely such a beast does not exist? All signal cable requires shielding or it is nothing more than power cable!

For what it is worth – there are a variety of colour combinations of shielded cable available, so I don’t think it really matters which colour goes to which pin. What is important is that pin 1 connects to pin 1, pin 2 to pin2 etc. Electrical conventions on the other hand are there for safety. This is why power cable only comes with specific coloured wires. No one is going to get killed if they wire their DMX up differently. I have DMX cable that is white/black, red/blue red/black and yellow/black.


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