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Author Topic: Two (or three) schools of thought: life/safety issues  (Read 7218 times)

Cailen Waddell

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Re: Two (or three) schools of thought: life/safety issues
« Reply #10 on: December 05, 2013, 09:47:27 am »


Do a gig in Chicago's McCormick Place.  The Teamsters will unload your truck.  The IATSE stagehands will move and set your gear, but the IBEW electricians run and hook up all wires.  ALL wires.

I had a friend do a gig there...  He didn't play well with others.  He ended up at the end of the night with a truck of teamsters, a group of stagehands and row of gear and no forklift driver.  Everyone claimed the ramp wasn't their jurisdiction.
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Keith Humphrey

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Re: Two (or three) schools of thought: life/safety issues
« Reply #11 on: December 06, 2013, 01:35:35 pm »

Do a gig in Chicago's McCormick Place.  The Teamsters will unload your truck.  The IATSE stagehands will move and set your gear, but the IBEW electricians run and hook up all wires.  ALL wires.

I used to do trade shows there. In addition the riggers will unpack and setup anything in a crate but you needed carpenters to unpack and setup anything in a cardboard carton. I also remember installing mainframe computer systems in Cook County and not being allowed to pull or connect the interconnect cables. Instead I had to point and tell IBEW electricians how and what to hook up even though I'm an electrical engineer. 
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Jeff Bankston

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Re: Two (or three) schools of thought: life/safety issues
« Reply #12 on: December 06, 2013, 11:16:28 pm »

Qualified does not always mean competent.


Steve.
+1 , right on !
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Mike Sokol

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Re: Two (or three) schools of thought: life/safety issues
« Reply #13 on: December 07, 2013, 02:43:13 am »

Found this week on another forum with regard to a discussion about hum and ground loops. 
"I've done dozens, maybe 100s, of sound installs for churches and clubs. First thing I do is put every piece of grounded equipment on a two to three wire ground adapter (ground lift)
Equipment grounding seems to be one of the most misunderstood aspects of power distribution, not only for the music industry, but also for the RV industry. I've been answering questions on my NoShockZone blog for months about floating neutrals on portable generators because none of the generator manufacturers' help desks will tell an RV owner why their voltage/surge protector is shutting down when run from their inverter generator. Even though code offers an exception for portable generators under 5KW with a floating neutral to not require a GFCI receptacle, that's been extended to the idea that ALL portable generators NEED a floating neutral. But as any of you who have hooked up big show generators know, that neutral and ground needs to be bonded together along with an actual ground rod.

If you think that sound crews take a lot of electrical shortcuts, you should see the crazy dog-bone and extension cord adapters used by RV owners to run a 50-amp/240-volt RV shore power plug from a 15-amp/120-volt receptacle in thier garage. And the RVIA is predicting 100-amp/240-volt RVs in the near future. These RVs are hooked up by many retirees who have ZERO understanding of electrical power or safety, sometimes standing in the rain on wet ground making connections without powering down the circuit breakers, and who will accept getting shocked as something normal. They just don't know how dangerous this can be.

I hope that everyone on this forum understands that any electrical shock is cause for concern, and  something as simple as a ground-eliminator adapter on a guitar amp can cause a deadly condition at any time. We really do need to educate licensed electricians and installers about grounding safety for musicians. I hope this forum helps all of us understand the dangers as well as best practices and code requirements.
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Stephen Swaffer

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Re: Two (or three) schools of thought: life/safety issues
« Reply #14 on: December 07, 2013, 11:29:22 am »

I agree with TJ on liability-it is a huge concern for me, but at the same time I want to help people that are really wanting to learn and do things the right way-as well I like to do things myself so I know they are done the right way and often that means asking for help myself.  I just wish we could get the lawyers to put the blame for troubles where it belongs-not where they think they can get money.  An area electrician was sued recently over the drowning deaths of 2 boys in a pool he had wired-but due to an error the lights did not work (boys drowned during a night swim).  He had previously been sued over the non working lights by the owner (a municipality) and settled for failing to complete the contact.  Obviously, for him to return and fix the lights would have been trespassing and the city failed to get the lights firxed-so 3 years later an accident beyond his control and he is in court again.  Many lessons there-but you can't expect the legal system to always use common sense and place blame appropriately.

Jeff is right-I have known many "qualified" if not competent people (journeymen who can't wire a3 way, etc) as well as many competent though technically not "qualified"people.  Part of the issue is that I rarely get asked about qualifications or skill-usually the only concern is price.  What many do not consider is that the lowest price is often not the best value-but many just don't care so they keep those that are willing to take short cuts in business.  Frankly, if I have a customer that needs to save money, but wants to do it right, often they will get a better price from me than the guy that just wants to be cheap-I really don't care to work for him.

Mike, I'll put local farmers up against your RVers any day!  Perhaps that might be an interesting thread! Often my first impulse on a farm is to find the main disconnect and kill the power before touching anything-the amazing thing is that farmers are the only group to get exempted from state inspection rules.  On a more serious note, is there really any difference between grounding safety for musicians, farmers, RVers, housewives,laborers, etc?  Again it goes back to understanding and doing it right-not just "its cheap and it works-even if I don't hookup that green/bare "extra" wire."
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Steve Swaffer

Mike Sokol

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Re: Two (or three) schools of thought: life/safety issues
« Reply #15 on: December 15, 2013, 06:05:32 pm »

Mike, I'll put local farmers up against your RVers any day!  Perhaps that might be an interesting thread! Often my first impulse on a farm is to find the main disconnect and kill the power before touching anything-the amazing thing is that farmers are the only group to get exempted from state inspection rules.  On a more serious note, is there really any difference between grounding safety for musicians, farmers, RVers, housewives,laborers, etc?  Again it goes back to understanding and doing it right-not just "its cheap and it works-even if I don't hookup that green/bare "extra" wire."
I would have to agree that farms are probably near the top of the list of dangerous places to be as far as electrical safety is concerned.

Here's a case study of a dairy farmer electrocuted by an electric power washer plugged into a corroded receptacle: http://ecmweb.com/bonding-amp-grounding/case-shocking-power-washer

And here's a very sad story about a pair of 14-year old girls electrocuted on a farm while de-tasseling corn in a field. The irrigation pump had its ground burned away the month before by a lighting strike, and it wasn't fixed. The puddles in the corn field were electrified by the water in hundreds of feet of irrigation pipe. http://wcfcourier.com/news/local/detasseling-electrocution-deaths-raise-questions/article_b6d9016e-b851-11e0-8b75-001cc4c03286.html

Sadly, I have dozens of incidents just like this in my files. And yes, electric shock issues are similar across all industries. That's why I find myself on all kinds of forums discussing electrical safety issues. And here's a final one for you to consider. Diesel pickup trucks often include a block heater for easy cold weather staring. Basically it's a hot-water heater element in the water jacket of the engine block. However, when a pinhole leak develops in the heater element, there's about 1 to 2 amps of current that flows from the line to the water. This trips any GFCI it's plugged into, with the result that the driver often disconnects the GFCI outlet or breaks off the ground pin on the plug and goes without a safety ground. So now you have a pickup truck with 120-volts on it's chassis/body and at least 1 or 2 amps fault current capability. So standing on the wet ground and touching the door handle can be deadly.

This is exactly why I started www.NoShockZone.org as a place to write about electrical safety issues for everyone, and why I agreed to moderate this forum. As a musician I'm most worried about stage shocks. But my industrial electric background makes me worry about all sorts of  larger building power installations. And my time doing instrumentation for and measuring missile guidance systems components makes me worry about any appliance plugged into a wall outlet.

Education is the key to safety, and it's great to see so many thoughtful and relevant electrical safety questions on this forum.  Keep up the good work...
« Last Edit: December 15, 2013, 10:27:53 pm by Mike Sokol »
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Jonathan Johnson

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Re: Two (or three) schools of thought: life/safety issues
« Reply #16 on: December 16, 2013, 01:36:01 am »

I was afraid this thread might turn into a flame war. I didn't mean to be a troll, and I'm glad it didn't.

I stand by answering questions honestly and correctly, with caveats. Hiring an experience, knowledgable professional with liability insurance is always the best policy, but I also recognize that's not always possible. In those situations having the right information is necessary.

Instead I had to point and tell IBEW electricians how and what to hook up even though I'm an electrical engineer.

Reminds me of the time I was troubleshooting a networking issue for one of my customers, who leased space in a hospital. Working with a rep from the hospital's IT department, we traced the connection problem to an incorrectly documented patch panel. (This was during an expansion of the hospital, so some of the network wiring had been rearranged and the documentation not completed.) We located the proper jack in the proper panel, and determined what was necessary to fix the issue.

Because of his position, the fellow from the IT department was not permitted to make changes; such a change would require a requisition be filed, go through the chain of command, and a week later someone might get to fixing it. (And knowing that hospital, something would have gotten messed up in the process and there would be even more extensive troubleshooting and requisitions.) However, because I was an outside contractor, I *could* make the change. So he watched me as I unplugged a patch cable and moved it over three feet to a different patch panel. And everything worked.
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Re: Two (or three) schools of thought: life/safety issues
« Reply #16 on: December 16, 2013, 01:36:01 am »


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