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Author Topic: A (long) WWYD electrical question  (Read 2034 times)

John Neil

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A (long) WWYD electrical question
« on: March 14, 2010, 09:38:52 pm »

I've reflected on the event and the chain of responsibility. I hesitate to admit a mistake on a public forum but it wouldn't be the first time.  Learning from the situation is the bigger issue to me.  Perhaps I take my work too seriously.

I'm not a [licensed] electrician.  I am not asking for electrical advice.

I was called as local crew for a touring gymnastics/fitness act.  1000 seat room, small stage.  I was not working for the room but as an employee of a stagehand staffing outfit.  The nature of my job was not sound related, but lighting and setwork.   The setguy is a jack of all trades, master of none, but he gets the job done.  He's got this collection of cables, chains, truss, motors, electrical, etc., for his set.  Probably a half-dozen things that are well below the margin of safety...if you only counted those with failure modes involving serious bodily injury.  My degrees and experience are mechanical engineering...throws flags sometimes.

During layout, traveling setguy discovers a cable for his motor controller is too short for our stage.  Venue sound offers a piece of surplus copper to construct a longer cable plus my time to transfer connectors to the new cable.  Non-union house, operating without a licensed electrician on hand.  My job is to extend his cable.

I had concern over the application of the cable.  His equipment isn't unpacked but my first guess would indicate this cable to be undersized for the load based on motor plates.  Setguy denies this...it's the same as what he has.  My main concern is that the cable will be HIGHLY undersized for the upstream over-current protection device.  I throw the flag and put my tools away to confer with the setguy.  He ensures me that he will not be running without proper current limiting.  He explains some arrangement of switches and boxes and seems to be explaining a distro.  This cable goes between distro and motor controller.

Cool, I build cable.  I already feel bad because part of "hired crew" is to do as they say, keep mouth shut.  Here I was causing trouble and questioning direction.

Hours later I get first glimpse of motor controller arrangement.  My cable applied as I feared, not how I had been informed.  Red flag.  Bigtime NEC violation.  If a setpiece cuts the cable...breaker doesn't trip, stage in flames.  Schoolchildren, etc.  I pull sound (supplier of the cable) aside to voice concern.  I am directed to house TM and raise concern in private, paraphrasing my understanding of NEC, legality, etc.

At this point, I feel I've done everything I can do.  If an accident happens perhaps I skirt liability for the cable, but I wouldn't be able to sleep.  Three shows go fine, show packs up and leaves town.  I am not questioning any decision made by the house TM.  I told him what I knew and the buck stops there.  Right?

Next time I'll ask more questions and make sure to know the application upfront.  In this case, I'd have to respond with "I'm sorry, I'm not qualified.  Let's call an electrician."  Or, "let's call an electrician I trust and ask about this first."  I can't blame the traveling setguy.  He was clueless and I didn't realize he didn't know what he was talking about.

So I ask: if I was working on your stage or with your equipment, what would you want me to do?  

At the time of construction, when I first realized a potential issue, I could have refused to participate.  Would you expect a third-party stagehand to move away from a task over a safety concern?  

Apparently I was the most up-to-speed electrical guy on hand.  Should I have pulled the cable from use at the time I realized it's unsafe use?  If so, does that authroity come from my construction of the cable?

What authority or responsibility does a third-party stagehand have for his work?  Stop a show?  Pull the disconnect?

Furthermore, would you expect a third-party stagehand to raise issues with equipment that he did NOT supply?  Does my responsibility end when I tell my superior?  What if my superior is ill-informed about the situation at hand...electrical code in this case?  What if that superior was the one who asked me to make the cable in the first place?  Ignorance vs. negligence on their part?

I'm quick to hide behind the "third-party" role, but perhaps the labor company calls me based on knowledge and quality of work.  Does this imply additional responsibility?

Worst case scenario, this show goes everywhere, asking third-party labor to do their unsafe dirty work and never owning up to their own equipment.

Am I too uptight?

Edit: typo.
Edit: add [licensed]
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John Roberts {JR}

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Re: A (long) WWYD electrical question
« Reply #1 on: March 14, 2010, 10:15:17 pm »

When in doubt, do what's right.

JR
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Tim McCulloch

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Re: A (long) WWYD electrical question
« Reply #2 on: March 14, 2010, 10:20:36 pm »

No, you're not too uptight.  You have a better grasp of the implications and realities than most folks.

As a stagehand electrician, I don't build or maintain for others.  My job is to tie them into the company switch, patch local circuits/transfers.  The carpenter's hoist power comes from me, but my job doesn't include fixing their stuff or building cables.  They have to do that so the liability is on them.

As a stagehand carpenter, I don't build electrical anything and it's my job to report to the steward/venue anything a road show does or uses that is obviously unsafe.

If the tour carpenter/tour electrician want to do something dangerous or stupid, the venue's Technical Director should be informed, as he/she is responsible for the facility and it's users.  If that person is cool with what's going on, yes, you've done all you can do at that time.  Knowing the location of the nearest fire alarm pull box, fire extinguishers, and power disconnect might be a good thing, too.  Oh, and have your exit path planned out...

Saying "I'm not qualified to that" is the right answer to those who'd have you do things you aren't qualified to do, IMHO.

Have fun, good luck.

Tim Mc
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John Neil

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Re: A (long) WWYD electrical question
« Reply #3 on: March 14, 2010, 10:34:23 pm »

Tim,

I was hoping you'd speak to me.  Your posts regarding safety always seem on target.

Are your personal calls often defined by union nametags?  For one reason or another, we get pretty loose around here about who is "able" to do what.

I assume you speak as a licensed electrician?  You seem to cite NEC line by line around these parts.

Not aiming to qualify or disqualify your points, but perhaps it would help to explain why things get undefined sometimes around here.
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Tim McCulloch

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Re: A (long) WWYD electrical question
« Reply #4 on: March 14, 2010, 11:09:38 pm »

Hi John-

When working as a stagehand I work in venues with IATSE contracts, so "head electrician" is pretty well defined as to duties and responsibilities.  Assistant electricians run cables; mount, patch, gel & focus instruments; set booms and other mounting equipment; assemble truss and battens.  None of us are expected to build cables for road shows, nor are we expected to maintain anything wiring related other than stage pin connectors on venue cables and venue fixtures.  The venues have licensed master electricians or contractors that fix everything else.

I've been crew where we crossed departmental lines, and the level of responsibility remains the same:  crew are not expected to manufacture or repair things for the road show.  Crew report unsafe materials or practices to their superiors, and follow up to ensure someone in authority approved the variance or the unsafe condition is remedied.  

I'm not a licensed electrician.  I can't do work in your home or business, nor would I want to.  My expertise is in entertainment power, and I have lively discussions with electrical contractors and staff, as many of them really don't understand what we do on the "LOAD" side of the switch.  As a group, entertainment electricians very concerned with safety and I think it shows:  you rarely hear of fires or electrocution from properly executed entertainment power systems.

The Code's Occupancies that concern what we do have been expanded and changed over the last 20 years.  Some inspectors live in the past, some in the present and a few in la-la land.  It pays to have a working knowledge of the documented standards one is being held to.

Have fun, good luck.

Tim Mc
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James Feenstra

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Re: A (long) WWYD electrical question
« Reply #5 on: March 15, 2010, 01:42:24 am »

John Neil wrote on Sun, 14 March 2010 21:38


So I ask: if I was working on your stage or with your equipment, what would you want me to do?
as my tour package is not the responsibility of the local crew to fix and maintain i wouldn't ask you to do anything in this situation. I'd do it myself or have one of my crew do it. by asking locals to repair/modify their tour package they're deferring liability on to them and it gives them a reason to cancel the show if their gear doesn't work because of something you've done.

Quote:

At the time of construction, when I first realized a potential issue, I could have refused to participate.  Would you expect a third-party stagehand to move away from a task over a safety concern?
most definitely...if you feel something is unsafe you definitely should refuse doing it

Quote:

Apparently I was the most up-to-speed electrical guy on hand.  Should I have pulled the cable from use at the time I realized it's unsafe use?  If so, does that authroity come from my construction of the cable?
yes, as because you're the one who made it and authorized the use in your house you'd be liable in the event something occurred resulting from that piece of gear

Quote:

What authority or responsibility does a third-party stagehand have for his work?  Stop a show?  Pull the disconnect?
if someone is bringing unsafe equipment into your house, it's you're responsibility to inform them as well as the senior person at the venue that the equipment they're bringing in appears to be unsafe. let the people paying you make the ultimate decision.
Quote:

Furthermore, would you expect a third-party stagehand to raise issues with equipment that he did NOT supply?
if there's genuine concern, absolutely
Quote:

Does my responsibility end when I tell my superior?
yes
Quote:

What if my superior is ill-informed about the situation at hand...electrical code in this case?
it still ultimately comes down to their decision
Quote:

What if that superior was the one who asked me to make the cable in the first place?  Ignorance vs. negligence on their part?
it'd likely be shared liability, as you could have refused to participate in unsafe work
Quote:

Worst case scenario, this show goes everywhere, asking third-party labor to do their unsafe dirty work and never owning up to their own equipment.
i had a similar show come into my venue tonight and refused to fix/operate/troubleshoot/etc their tour package. i gave them everything from the house they needed and was on site to answer any house-related questions they had. they seemed to have a rather large problem with me not doing their work for them.
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James Feenstra
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Art Welter

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Re: A (long) WWYD electrical question
« Reply #6 on: March 15, 2010, 12:50:49 pm »

John,

I’m curious, what was the amperage rating of the motor and upstream circuit breakers, and what was the cable gauge and amperage of the connectors ?
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E. Lee Dickinson

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Re: A (long) WWYD electrical question
« Reply #7 on: March 15, 2010, 02:14:44 pm »

Also, just to be clear - were you building a motor supply cable, a motor control cable, or a combo/7pin type of cable?

I ask because the motor control cables, at least on CM motors with black pickles, only carry enough current to trip the relay, not to power the entire motor. The CM manual says you can go up to 135' on #16, 220' on #14.

Orange pickles indicate the motor does not have relays, and that the pickle carries the entire motor current.

Not sure how to tell by looking at the motor housing - I should go check the plates to see if it's indicated.
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E. Lee Dickinson
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John Neil

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Re: A (long) WWYD electrical question
« Reply #8 on: March 15, 2010, 06:29:56 pm »

Art Welter wrote on Mon, 15 March 2010 11:50

John,

I’m curious, what was the amperage rating of the motor and upstream circuit breakers, and what was the cable gauge and amperage of the connectors ?


Lee and Art,

I respectfully decline the invitation to turn this into a technical matter.  My intent was to invite advice regarding the moral/legal/responsibility issue of a situation in which I regret participation.

We're not talking about chain motors here.  Industrial drive motors with gearboxes and propeller shafts and such - three hots and a ground to every device.  Variable speed, reversable.  The cable I was asked to construct was a current carrying item - supplying grid power to the main motor controller which then distributed power to each of the motors involved.  It was not a control cable of any kind.  I am familiar with chain motor control and controller pickles.  This was a different situation beyond the realm of items typically seen on a flown sound and lighting rig.

Thus, technical issues specific to the device may not belong to this forum, but my other concerns remain relevant.

I can't recite from memory the code regarding the current capacity for various sizes of wire, nor am I well versed in the de-rating for multiple conductors in a single jacket.  I do know that these concerns exist and to watch out for them...perhaps even look them up...if setting up a rig on my own or assembling a package for a sound company that I may work for.

I don't work as an electrician, so I feel that I have a sufficient working respect for code inclusions that govern my usual activities.  I threw a flag based not on the copper's current capacity to load relationship of this situation, but on the terminal capacity relationship of the copper to the most limiting upstream circuit breaker.  The upstream breaker was very large.  The copper was very small.  Use your imagination here.  

If you are concerned that I perhaps threw a caution flag over a NEC compliant situation, let's take this to PM.  Otherwise, I allowed myself to become involved in a technical matter that I should have stepped away from and wanted advice regarding the handling of responsibility in any similar future situations.
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E. Lee Dickinson

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Re: A (long) WWYD electrical question
« Reply #9 on: March 15, 2010, 06:56:07 pm »

Understood.

I would say you're pretty well guaranteed to get named in the lawsuit when, as an independent laborer, you manufacture an item for use in the production. It then becomes a contest of who has the best lawyer - something I'd want to bet on even less than on the safety of an improperly-protected cable.

You definitely got stuck in a hard situation: You raised the correct questions and were given what you believed at the time to be satisfactory answers.

If I were the crew leader and some hand came along and unplugged something because he thought it was unsafe, I would be furious. But I would sure think twice before plugging it back in, myself, and taking the personal responsibility.
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