Wanted to start a discussion on temporary power hook-ups, like those for shows and other events where a feeder is connected into a building's wiring system to feed a portable breaker box ("Distro" in showspeak.)

But any temporary where you've wondered how someone didn't get fried or buildings/equipment torched is fair game!

In my high school days, I actually put together a feeder system which worked, but was not one I would ever do again. It was for lighting of a small portable stage some friends built. The feeder was some salvaged 8/3NM Aluminum cable, one end of which terminated in a 6-position GE breaker box. The feed end was lugged to the neutral and ground busses, the phase connections were (everyone cringe here)200-amp rated battery jumper clamps!! [Linked Image] How I never managed to kill someone or burn up some feed lugs I'll never know. Ahh, the stupidity of youth!! At least I did have some common sense. I wore rated rubber gloves and had a safety observer (out of harm's way) when I hooked up / disconnected. Oh yeah, and how about the 65' of unprotected feeder strung across the floor? I obviously had the electrical gods watching over me...

A few years later, I saw another crew with a similar set-up, but no clamps. No, thier phase connections were always done hot by loosening the panel's feeder [under load!] and double-lugging. Always good for a fireworks show. That clown never wore gloves, just used a taped-up screwdriver or ratchet.

When I worked for a sound company in Nor. Cali, I was introduced to cam-loks. A wonderful device, made hookups fast and relatively safe. As long as you did them with no load on and in the right sequence. The only real problem was there seemed to be no standard for the gender of the line side feeds installed, so you had to carry a set of "turn-arounds" (or "he-he's" and "she-she's") to get your feeder to fit. The connectors were (and still are) bloody expensive though.
The idea was to make temp power safe and relatively foolproof.

But as the saying goes, make something foolproof and along comes a better fool....to illustrate:

The safe, proper proceedure to hookup is:
All distro breakers OFF [i.e., no load on feeder]
Cam-lok disconnect switch/breaker OFF [where installed, some venues didn't have disconnecting means AT the cam-lok location]
Connect feeder in sequence:
Ground;Neutral;Blue;Red;Black
Ensure all cams are fully locked and tight;
Close disconnect/breaker;
Turn on DISTRO breakers as needed.

To disconnect:

ALL DISTRO breakers OFF;
Cam-lok breaker/switch OFF;
Pull cam-loks in sequence:
Black;Red;Blue;Neutral;Ground

Well, one fine night after a great show I look across the venue to see one of our roadies crouched over by the cam-loks. I wasn't too sure what he was up to until I noticed the ground cam-lok in his hand. He was just about to pull the neutral when I let go with a tirade that would blister the pixels of your monitors!! I then made the proclamation to everyone within the greater Sacramento area that the next person to touch that feeder without my direct supervision was going to lose the use of their hands for life!! (Actually I also threatened to remove certain other body parts as well, but this is a family-friendly forum so you get the idea.)

Why was I so upset? Because this moron was about to pull the feeder with our dimmer pack connected and live, and also my monitor mixing board was still on as well!! About $75,000+ of equipment about to get a smoke test!!

After my boss heard the ruckus and realized how serious the situation was, he backed me up.

Since then, I have built my own distro for my portable projection set-up. It uses a Crouse-Hinds 3-phase panel (My large Xenon lamp rectifier needs 3-phase power) and connects with feeder lines (#2 cable, 5 wire.) I can power my entire set-up, including sound, from this one distro. All feeder ends are bare, I lug to the ground and neutral, and pull phase power from a circuit breaker (100amp max) in the panel. So far, I've not run into situations where I've needed cam-loks or didn't have the breaker space available.

I originally built this set-up for an outdoor show I used to do, I'd rent a 55kw quiet genny to run the rig, and connect to the genny. Oh what fun to drive the ground rod for the genny, then have to pull it when we were done!

I would bond the neutral and ground at the genny, but it seemed that depending on who I asked, I wasn't supposed to. But the L-N voltages were always stable and I had no equipment or audio noise problems. Hmmm...that cuold make a whole 'nother thread...

So let's hear it from you folks.... [Linked Image]


Stupid should be painful.