DMX cable-path issue

Another thing you can try is if you have tie lines or mic sends anywhere nearby, you can always patch DMX to a 3-pin XLR and run it through the audio wiring.
 
Another thing you can try is if you have tie lines or mic sends anywhere nearby, you can always patch DMX to a 3-pin XLR and run it through the audio wiring.

Keep in mind depending on the cable run in your facility, microphone cable has a different capacitance than DMX cable. Some newer installations have lines that are certified for digital as well as analog signals, but it is not commonplace yet. Depending on a lot of factors, this may or may not work reliably.

I personally would not borrow a mic run for DMX. I'd use a Cat5e/6 based solution, as it meets the required specifications for DMX [1], and is cheaper per foot than DMX cable you'd get from a supplier. Cat5e/6 is easy to pull, easy to terminate. I'd pull these cables home run between a control location (backstage rack, booth) into a patch panel.

Instead of soldering to XLRs I'd suggest terminating in the standard RJ45 (or EtherCon to ruggedize it), and using a proper adaptor as needed [2]. This way, the line can be used for a variety of purposes (DMX, video, audio, ethernet, etc).

If you are picking your brain to find a pathway to where you need to be, you should really speak to a qualified electrician or data communications installer. They will be able to tell you what type of cable you may run where and how. Factors like conduit, plenum rated vs non, etc. If it's a temporary run (doesn't sound like it), and if it was possible to do it safely, I'd string up the Cat5e and remove it immediately after (like most stage cabling). Ideally though, you'd start building your Cat5e/6 distribution system, home run to your booth, to allow for a lot of flexibility and future use. It's also way significantly cheaper to have an installer pull say, 6 lines at once, rather than have repeated visits over the years.

Using High Voltage rated Cat5e/6 cable was suggested. I've never seen this product, nor would I ever recommend putting HV and LV in the same run. It violates so many cabling standards and makes it a real pain to maintain. Not to mention you need an HV qualified person (read: licensed electrician) to perform any of the work on it legally. Low voltage systems you can maintain yourself, I would suggest under the guidance/suggestion/education of a certified cabler. Seriously, you're better for lashing a Cat5e cable on the outside of a power conduit than getting cable rated to go IN it. And as a reminder, never lash cable onto any fire detection or control systems, and always abide by your local codes.

I'm sure there is bound to be a low-voltage pathway you can utilize into the existing floor pockets. Otherwise you should have a sleeve of EMT (4" if possible) installed in a corner to facilitate passing cables from above deck to below. They'll probably require you to install fireproof pillows in it per code, which can be temporarily removed for adding or subtracting cables.

Sorry if this sounded too stringent, I know a lot of things in the theater just get done as easily as possible -- as the show must go on, but they should always be done safely, and if possible with a long range plan in mind. I had spent 4 years of my life as a data communications technician at a large public university (with about 50k heads roaming around the campuses). There are people who can look at your situation (physically) and solve your problem in a heart beat, and extensive knowledge/training in the codes and standards (local, NEC, BICSI, etc). Take advantage of them.

[1] ESTA Working Groups - DMX over Cat5e
[2] C-Point XLRJ45 Adapters
 

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