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[TJ (Tom) Cornish]

The show I ran last week involved using both my distro equipment and the venue's distro panel which had just a few issues:
- 4/4 SOOW cord with cams directly connected to the #4 wire (issue 1)
- the outer jacket cut off at the load end of the 4/4 cable with no strain relief to the panel (issue 2)
- no main breaker (BIG issue 3)
- 24 20A breakers feeding receptacles on the distro board (BIG issue 4 related to no main breaker)
- several damaged or miswired receptacles that tested with no ground (issue 5 - I taped over these and labeled their condition)
- The house tech had patched this into their 400A company switch (HUGE issue 6)

There must be some manual out there on how to (incorrectly) build a "hotel distro".  Nearly all of these I see use 4/4 cord for north of 100A (rating for 4/4 SOOW is 55A), some like in this case with no main breaker, but the potential to pull 240A per leg via the massive number of branch circuits hanging off this thing.

I asked the guy to move it to their 100A switch and educated him a bit about the potential issues. 

[frank kayser]

And I bet it cost an arm and a leg to rent...
One could swallow the cost if the equipment were up to par.
frank

[TJ (Tom) Cornish]

And I bet it cost an arm and a leg to rent...
One could swallow the cost if the equipment were up to par.
frank

Thankfully it was included in the room rental, so the only issue was the risk of a fiery death for hundreds of people.

[Ted Christensen]

The show I ran last week involved using both my distro equipment and the venue's distro panel which had just a few issues:
- 4/4 SOOW cord with cams directly connected to the #4 wire (issue 1)
- the outer jacket cut off at the load end of the 4/4 cable with no strain relief to the panel (issue 2)
- no main breaker (BIG issue 3)
- 24 20A breakers feeding receptacles on the distro board (BIG issue 4 related to no main breaker)
- several damaged or miswired receptacles that tested with no ground (issue 5 - I taped over these and labeled their condition)
- The house tech had patched this into their 400A company switch (HUGE issue 6)

There must be some manual out there on how to (incorrectly) build a "hotel distro".  Nearly all of these I see use 4/4 cord for north of 100A (rating for 4/4 SOOW is 55A), some like in this case with no main breaker, but the potential to pull 240A per leg via the massive number of branch circuits hanging off this thing.

I asked the guy to move it to their 100A switch and educated him a bit about the potential issues.

This scares me a bit. Thats in my neck of the woods.

[TJ (Tom) Cornish]

This scares me a bit. Thats in my neck of the woods.

Hey Ted - this one was out-state, but I've done several hotels in MPLS that have alarmingly similar gear.

It can be a "darned if you do, darned if you don't" situation - usually you get in bigger trouble trying to fix someone else's equipment than if you use it as is as safely as you can (within reason - there is definitely a point at which you need to turn down something that can't be used safely).  In my particular case, I load tested and labeled every circuit so I knew what leg they were on and which receptacles were safe, and taped over the ones that weren't.  I kept my usage to 4 20A circuits - two per leg, so I knew I would be under the rating of the feeder cable.  That plus a little education of the venue folks on why it was dangerous and a strong suggestion to only plug this guy into the 100A switch was the best I could do in the circumstances.

[Rob Spence]

Hmm, reading the thread title I wanted to complete the sentence with
", shock hazard, fire hazard, sharp edges, and expensive"

I did a gig last weekend in a Boston hotel. We needed at least 3 circuits for the rig. The rooms have all (well, I did find one) duplexes disabled but have 20a 2phase twist connectors in many places. In fact there was one at each rear corner of the stage on support pillars. They supplied cords with 4" boxes and duplexes split across the phases. One measured fine but the other showed a missing ground on the 3 light tester. I asked engineering to check it. They replaced the cord set but still no ground. Must be broken in the wall ! They were not the least bothered by this.
 No other power close by. Sigh...


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[frank kayser]

Thankfully it was included in the room rental, so the only issue was the risk of a fiery death for hundreds of people.

Yeah.  That's a better order in levels of concern.  Big worries (people), then the little ones (dollars).

[Stephen Swaffer]

One of the odd things about electrical licensing in Iowa is that a company (factory/venue-whatever) can hire someone, deem them "qualified" and they are allowed to wire to their hearts content.  In a job market where most trained, licensed electricians are sought after, those who cannot get a license but "know how to wire"  wind up in these types of jobs-which typically offer lower pay.  Keep in mind who is maintaining the distros you are using!

People don't like inspectors running around and they balk at paying electricians and too often have the attitude that if the lights are on and nothing is smoking all is well!

[TJ (Tom) Cornish]

One of the odd things about electrical licensing in Iowa is that a company (factory/venue-whatever) can hire someone, deem them "qualified" and they are allowed to wire to their hearts content.  In a job market where most trained, licensed electricians are sought after, those who cannot get a license but "know how to wire"  wind up in these types of jobs-which typically offer lower pay.  Keep in mind who is maintaining the distros you are using!

People don't like inspectors running around and they balk at paying electricians and too often have the attitude that if the lights are on and nothing is smoking all is well!

Conversely (not disagreeing with you, BTW), licensed electricians are typically unfamiliar with the nuances of entertainment power.  The monstrosity in question was built by a licensed electrician.  I suppose there's some table somewhere that says #4 wire is OK for 100A in some goofy circumstance (it definitely isn't 100A for SOOW cord), and maybe at one time there only was a 100A switch, hence the no master breaker and undersized wire.  In any case, working to increase the knowledge of fellow production folks (and commercial electricians when possible) is a very good thing.

[Stephen Swaffer]

I would be the first to agree that a "licensed electrician" does not guarantee quality-or even correct work. (And I have learned things I overlooked from others on here.) Unfortunately, many employers do not understand how broad of a field "electrician" is-just as you would not expect a "sound tech" to be able to handle every job in every gig from bar gig to national act to stadium install.  They really should provide industry specific training.

The most likely scenario is that #4 is good for residential 100 amp services (even though ampacity is less than 100 amps-normally requiring 90 amp breaker), so people are used to using it for 100 amps.

Most "incomplete" reference materials will not include the SO tables-and if you are not a full time electrician the cost of a code book can be intimidating.  Perhaps an "Ugly'S" style reference for the entertainment industry would be useful (maybe there is already something similar).  Voltage drop tables, etc seem to be more critical in this industry-certainly more so than in a residential application.  Truss loading tables might be more useful than conduit bending guides?

[ProSoundWeb Community]