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Stage electrical service for musicians


John Roesli:
Just want to make sure I have this right. Appears to be some changes in the NEC/NFPA 70 for 2020 that allows some flexibility in using SJOOW type cable, however it doesn't seem to go as far as allowing it on stage. 
I'm trying to improve/bring to code the stage electrical service on portable stages, primarily for music performance.  I'm using some hard rubber outlet boxes with double duplex 5-20 and powercon in/out. They are from OAwindsor for those familiar. One run from spider box (20amp protected circuit) along UL to UR and one run from spider box outlet (20amp protected circuit) DL to DR. Spacing and number of outlets on each run would vary depending on stage size and band requirements, but most would be 3 outlet boxes on each run spaced 10 to 15 feet apart. As I understand it this requires SOOW or equivalent type cable and most reasonable to fit the powercon connections would be 14/3, which limits the load to 18 amps. I've considered placing a Furman unit with a 15amp breaker upstream in-between the stage outlets and the spider box, but reading through the NEC/NFPA 70 I can't decipher how those Furman units are defined, any clarity on that would be greatly appreciated. SOOW 12/3 would be the proper cable, but I haven't found any with an OD of 15mm or less that will fit the powercon connectors. The other option would be to use 12/3 SJOOW and make the case that the runs are UL to UR and DL to DR where there is literally no foot traffic. Portable stages used are typically anywhere from 28" to 48" high so you can't walk over the cable downstage without falling off and upstage they are between the backline gear no mans land and the stage handrails where only a tech or the musician would access. Appreciate any advice, guidance, recommendations or directions.

John Roberts {JR}:
I am a big advocate of using GFCI protected outlets for backline stage use.


John Roesli:

--- Quote from: John Roberts {JR} on September 01, 2021, 11:43:37 AM ---I am a big advocate of using GFCI protected outlets for backline stage use.


--- End quote ---
All of the 50amp 125/240 spider boxes I have seen lately have a GFCI on each circuit.  It makes more sense to me to use the 12/3 SJOOW and run direct to the spider box with the 20amp GFCI outlet.  I'm just not sure
if it meets the  "a location that inherently prevents physical damage to the cord..." or what would be needed to do that, e.g. gaff tape, rubber mats etc.  Not sure if that's the same as your comment on GFCI or if you meant on each outlet. 

Jeff Lelko:
Hi John,

This topic was discussed at length just last week right over here.

The TL;DL:
- Use 12/3 SOOW (too many "gotchas" if going with lighter gauge or SJOOW for general use). 12/3 SOOW will fit in standard Blue/Grey PowerCon connectors.
- There is no need to use a Furman or other type of power conditioner.  Simple quad boxes and rack-mounted power distros are fine for powering generic equipment.
- Consoles and other digital equipment sensitive to power anomalies should go on an UPS.  The "online double-conversion" flavor are typically considered the best choice but are also the most expensive (and generally seen as overkill by most users here). 

Hope this helps!

Brian Jojade:
If you're going to deploy on a stage where you potentially need to 'make the argument' that your cable selection passes code, you're better off just sticking with SOOW cable.  Not worth it if you end up losing the argument during the inspection.

Now, if your usage is on stages that won't get inspected, it's up to you to deploy what you feel is up to code.


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