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[Steve Cook]

Clint,
I saw the title and knew this would be an interesting read. Try not to be insulted by a group of people whose interests are to protect and educate a community, which now includes you.

This forum has been such an asset to myself and my band, the main one being the vigilance that I have towards safety at our gigs.  And it's come from threads like these.  I may have upset some people in my band over a frantic 'NO!' and have gotten into heated arguments over things at gigs in previous bands, but I will continue to make certain we practice a top level of safety at all of our events. 

I really like the fact that in my current band, we're all on the same page and focused on doing things the right way.  And it's all due to the helpful warnings from this forum.

Thanks guys.

[Chuck Simon]

[quote author=Charlie Zureki link=topic=135184.msg1265763#msg1265763 date=1323993197

   If these Bars/Clubs/Pubs were anywhere near being interested in taking pride and care of the entertainment that they host...they'd provide a stage with safe and ample Electrical Service.

   But, I NEVER met a Bar owner that wasn't an a-hole.
[/quote]

After 30 years in this business, I'm sorry to say that I could not agree more with that opinion!  Sad but true.

[Michael Ardai, N1IST]

The other hazard with the dual-edison setup is that as soon as you plug one in, the other male plug ends up with exposed energized pins if you have any load connected to the distro.
/mike

[TJ (Tom) Cornish]

So to be clear, the problems with my distro are:

Shared neutral and my unconventional tapping technique by summing two Edison plugs to achieve 220 volts.

I never need more than 30amps 220 volts, so my main breaker and 10/4 SOOW feeder is sufficient and there's no need to upgrade it.

I'm not sure why the shared neutral is a problem... My home and the shop where I work both have shared neutrals. It's a rather common practice. If it is illegal, I'll find another way. Incidentally I have two 15 amp breakers in the breakout box, so its redundant protection. The only issue I've encountered is with GFCI circuits. I've researched it but it can't make it work; save removing them temporarily, during which time, they're not available to anyone else. This was the original motivation for my question.

I thought it was a safe solution to a real problem that causes a lot of trouble, i.e. blown breakers that interrupt shows, overdrawing circuits, etc...

Here are some pointers.  This is a non-exhaustive list and is not necessarily specific direction to a complete, legal, safe system.  If you're in the USA, the general governing body is the NEC, and everything you do is subject to the official having jurisdiction at your venue -  a city inspector, state inspector, etc.

- Direct tie-in:
Unless you're a licensed electrician with legal permission to do work on the electrical service at your venue - you can't do it.  Period.  It's incredibly dangerous to work on a live panel - especially the main lugs side where there's a ton of current available.  200A 120/208/240 volts will melt any screwdriver or wrench that gets shorted, and can ionize the air around the main lugs, causing an arc flash.  Do a YouTube search for arc flash if you need any more discouragement for this. 

Apart from the very real physical dangers, there are a ton of liability issues as well.  There's a saying:  "Whoever touched it last, owns it."  Any future electrical problem the venue may have, up to and including a building fire, will likely be blamed on anyone who the lawyers can find.  If an unqualified person did work in the building, they're shark bait.

This leaves basically 2 options:  Use the venue's available service, whether one or more Edison outlets, or a high current plug designed for that purpose, such as a NEMA 14-50, or hire an electrician to do the hard-wire service connection and disconnection.

-Edison circuits:
For Edison circuits, you can get many of the benefits of a distro with the "Poor Man's Distro" principle - which is really nothing more than shorting all the grounds together from your supply circuits.  This solves most of the ground loop issues you will have, and does not open you up to legal liability, as you are using building equipment "as-is".  Any other attempted combination of Edison circuits into either higher current (paralleling same phase circuits) or higher voltage (cross phase) is dangerous, and really doesn't accomplish anything anyway, unless you have 208/240 volt only devices.  You're still limited to the power available from the sum of the Edison circuits, so you might as well just plug in directly.

- Higher-current outlets:
The NEMA 14-50R is a popular receptacle for stage power purposes as it gives basically 6 20A 120V circuits on a 4-wire plug with 4/4 SOOW cord supplying your distro.  Anything smaller than this borders on a waste of time as a 14-20 is only 2 circuits, and a 14-30 is only 4 15A circuts.  The cost difference to the venue between a 14-50 and something smaller is very little, so if you decide to ask your regular venues to install heavier power for you, this is what you want.

- Partial energization:
All supply wires must be energized or de-energized simultaneously via a multi-pole breaker or disconnect.  Bonding Edison circuits together breaks this rule and is dangerous.  Someone could turn off what they thought was the supply, and work on your system, only to find that it's still energized through another source.

- Shared neutrals:
Shared neutrals are acceptable in some circumstances when the supply wires sharing the neutral are simultaneously switched.  There are some caveats here, depending on load type and neutral wire sizing.

- Overcurrent protection:
Circuit breakers are there to protect the supply wiring.  Any time you're stepping down the ampacity of the cabling (going from a 200A company switch to #4 tails to your 50A distro for example), you need to have appropriate overcurrent protection for the wire size.  This almost always means you need a master breaker rated to protect your feeder cable, and downstream breakers to protect the Edison circuits and L14 or L21 breakout circuits.

- GFCI circuits:
If they're there, they need to stay there.  If you're having trouble with these, your gear is damaged - failing MOVs in surge supressors, etc.  Get your gear fixed.  There's no reason you can't use GFCI circuits.  If you're using a distro with a generator or outside, GFCI protection may be required.  Be prepared for that.


- Inspection/listing:
It is completely possible to build an up to code home made distro, with the right knowledge.  The problem is, even if you do, how does the world know you did it right?  Who inspected and certified it?  Is it really worth it in the end compared to using a pre-fabbed product such as the Peavey distro, or MotionLabs stuff?  Even if you're never "inspected", how do you go from "I think it's right." to "I know it's right."? The devil is in the details, and while it's not generally hard to get it "working", it's quite another matter to get it "safe and correct".

-Inadequate/wrong/unsafe building wiring:
If something looks bad, don't use it.  It's far better to downsize your gig to fit on a safe supply than to risk personal injury or property damage.  There can be a "The show must go on" attitude, which sounds admirable, but if that means putting your band and your audience in a proverbial (or God forbid, acutal) burning building, it's not admirable.  If it's the situation really can't meet your needs, either get better venues, or if you really must play there, get venue permission, then hire an electrician yourself to install the NEMA 14-50R plug mentioned above.

- Testing:
Always test everything for appropriate voltage and wiring.  Even fairly new construction in "nice" buildings can have problems.  If it's wrong, notify the venue and don't use it.  Don't try to fix it yourself, or you may "own it".

- The Ego principle:
It's really fun to bring a huge pile of gear to your gig.  It's fun to turn it up to 11 and have 40,000 watts of light blasting the stage and/or dance area.  The economic reality is that if you can't get adequate power to run your 12/side line array over 12/side double 18" PA in the 75-cap bar, you've brought too much stuff.  Trying to bend the rules perpetuates unsafe expectiations, and eventually someone will lose.  Don't let that be you.

[Clint Miller]

The other hazard with the dual-edison setup is that as soon as you plug one in, the other male plug ends up with exposed energized pins if you have any load connected to the distro.
/mike

I don't think so...  There would have to be faulty wiring for that to happen.  I always make sure the polarity AND ground is working before using them.

Not all bar owners are goobers.  I've even gotten one to install an L14-30 recepticle outside so I don't have to remove the GFCI outlets.

I'm in Northeast Ohio, by the way.  I work from Cleveland to Columbus to Ashtabula.

When I can afford it, I'm going to get a 10K generator, so this will be a moot issue!

For all of the excessive electrical regulations, you would think that this would be something that was standardized by now.  I'm amazed there is not some code that dictates the wiring of audio systems like the wiring of a stove...

My system in very efficient and draws little power compared to the old days.  All of my lights are LED, my amps are digital... Back in the day, my par cans alone tripped every breaker/fuse that I could find!  When I run my whole system for festivals (sound & lights), I can do so with a 5000 watt generator and not blow anything.

I stand by my system.  I still think it is a much safer system than a bunch of extension cords that could end up on the same circuit anyway!  That's not to say there isn't room for improvement.  But until someone can show me WHY my method is dangerous, I'm leaving it alone.

I will post a schematic later to demonstrate what I'm doing.  I should also make it clear that none of my equipment is running 220 volts.  My crown aps could be run 220, but I haven't done that.  Essentially, all I'm doing is creating my own sub-panel off the main panel to allow me to protect everyone AND my equipment.  If there is some potential fo back feed from one of the 110v lines, that would be a definate concern...

I like having spirited debates.  I like learning from guys who have been doing this a lot longer than me.  I have a lot of respect for experience.  But there can be new things too.  I have one tech who works for me and swears that digital is a fad, which will pass.  THAT is what I have no patience for... 

[TJ (Tom) Cornish]

I don't think so...  There would have to be faulty wiring for that to happen.  I always make sure the polarity AND ground is working before using them.

You don't know that there isn't faulty wiring in the building, and it's not always possible to test for it - loose neutrals, neutral/ground reverse, etc.

Not all bar owners are goobers.  I've even gotten one to install an L14-30 recepticle outside so I don't have to remove the GFCI outlets.

I'm assuming you haven't read my other reply yet, so I won't beat you up too badly, but DON'T DO THIS!!! DO NOT MODIFY BUILDING POWER!!!

When I can afford it, I'm going to get a 10K generator, so this will be a moot issue!

The generator you want if you want 10KW is $15,000.  Construction generators are garbage and not suitable for event power.

For all of the excessive electrical regulations, you would think that this would be something that was standardized by now.  I'm amazed there is not some code that dictates the wiring of audio systems like the wiring of a stove...

It is.  What's not standard that you're referring to?  In addition to the general NEC, there are specific sections that relate to entertainment power.  There are venues that are not up to code/don't have your particular needs in mind, but that doesn't mean there aren't standard methods and regulations.

My system in very efficient and draws little power compared to the old days.  All of my lights are LED, my amps are digital... Back in the day, my par cans alone tripped every breaker/fuse that I could find!  When I run my whole system for festivals (sound & lights), I can do so with a 5000 watt generator and not blow anything.

I stand by my system.  I still think it is a much safer system than a bunch of extension cords that could end up on the same circuit anyway!  That's not to say there isn't room for improvement.  But until someone can show me WHY my method is dangerous, I'm leaving it alone.

It's illegal - that's clear.  If you still don't care, that's telling.

I will post a schematic later to demonstrate what I'm doing.  I should also make it clear that none of my equipment is running 220 volts. 

Which means you have absolutely no reason to try to bond Edison circuits together - it gains you nothing, and is dangerous and illegal.

My crown aps could be run 220, but I haven't done that.  Essentially, all I'm doing is creating my own sub-panel off the main panel to allow me to protect everyone AND my equipment. 

Essentially what you're doing is shortcutting for wiring convenice (specifically the bonding Edison thing) without regards to safety ramifications.  The fact that you don't understand/don't believe that this is not OK doesn't change the reality.

I like having spirited debates.  I like learning from guys who have been doing this a lot longer than me.  I have a lot of respect for experience.  But there can be new things too.  I have one tech who works for me and swears that digital is a fad, which will pass.  THAT is what I have no patience for...

I like having people not die.  Is that a fad?

[Charlie Zureki]

OK... Per your last post..... Even after all of the good advice that you've been given, per your request, you are apparently going to ignore it....

  It is Illegal to circumvent, or alter any safety device such as a GFCI outlet.

  Your homebuilt distro does not conform to the NEC codes..for many reasons, including energized circuit indicators.

  Do it you way, you are apparently willing to accept the liability. As other's have pointed out that now, you've made your case public via the web. 

  By the way...whatever Amps you were referring to...they are not Digital, they're analogue, just like ALL of the other Amplifiers by ALL of the other Manufacturers in the World. Don't let Marketing Hype teach you!

  This site is a great place to learn about Sound Systems, its components and the Arts and Science of Audio. General inquirys about related subjects are always welcome.

   Good Luck, Good Bye...I'm done
  Hammer
   

   

[Clint Miller]

So, alright... I’ll acquiesce.

You have pointed out a serious problem I overlooked when tying the edison plugs together, and then someone working on the subsequent circuit...

My honest question is this: Why is it OK to run common neutrals that are on seperate circuits in a panel?  I have several of them in my house, where they ran 14/3 romex...  The Red is on 15 amp circuit and the Black is another.  Those breakers are not tied together. One can be turned off while the other is still live.  If the neutral was removed, that would be a burner.  In my system, that wouldn't be a problem, because there's another neutral and ground, which are all bonded in the panel.  just sayin'...  I WELCOME the flaws to be exposed. 

Please understand, I'm not trying to defend my system.  I'm trying to make it as safe as I can. Legal would be good too.  That's why I asked. 

I'm going back to the drawing board and when I reinvent the wheel, I'll see what you guys think.  My wounds should be healed by then!   

OK... my amps are not digital...  but they're marketed as such.  They're MUCH more efficient than my old Peavey CS amps, which allows me to have a bigger system with less power.

Hammer, how old are you???  I have this vision that you're 88 years old and really grumpy.  I bet I'm wrong...  Don't hate me because I'm a young whipper-snapper! (Which I'm not)

[TJ (Tom) Cornish]

So, alright... I’ll acquiesce.

You have pointed out a serious problem I overlooked when tying the edison plugs together, and then someone working on the subsequent circuit...

My honest question is this: Why is it OK to run common neutrals that are on seperate circuits in a panel?  I have several of them in my house, where they ran 14/3 romex...  The Red is on 15 amp circuit and the Black is another.  Those breakers are not tied together. One can be turned off while the other is still live.  If the neutral was removed, that would be a burner.  In my system, that wouldn't be a problem, because there's another neutral and ground, which are all bonded in the panel.  just sayin'...  I WELCOME the flaws to be exposed. 

The short answer is that it's not OK anymore. NEC article 210.4B "Disconnecting Means. Each multiwire branch circuit shall be provided with a means that will simultaneously disconnect all ungrounded conductors at the point where the branch circuit originates."

http://www.nfpa.org/assets/files/pdf/rop/70-a2010-ropdraft.pdf

Please understand, I'm not trying to defend my system.  I'm trying to make it as safe as I can. Legal would be good too.  That's why I asked. 

I'm going back to the drawing board and when I reinvent the wheel, I'll see what you guys think.  My wounds should be healed by then!   

I understand the desire to exercise knowledge and build something, but I would suggest not reinventing the wheel - the existing legal wheels out there aren't really that much money, and will be less likely to be problematic.

Once again - combining multiple Edison circuits into a "distro" offers no benefit and lots of downside over using them separately.  Whatever your future power plans may be, please don't do this.

Edit:  Shpelign

[Bob Leonard]

Tom,
I'm afraid your years of wisdom and desire to be more than helpful have been overlooked and are unappreciated by the OP.

I have worked many venues of all sizes and types over the past 45 years. I may have seen the worst, and I may have seen the best, but one thing that stands out in my mind is that smaller venues, those up to 5-600 people, seldom if ever need a distro for stage power.

I have not seen, played in, or worked sound in any small venue where 2-3 20A circuits were not enough to power the equipment required to do the job. And by equipment I mean sound, backline, and lighting. I have worked many outdoor "concerts on the common" in this area where all that has been available are 20A outlets centrally located 50 to 100 feet from the stage. In every one of those cases I have been forced to revert to using extension cords.

But here's where I'm headed.

There is absolutely nothing wrong with using quality #12 extesion cords if the need calls for them. And by quality I mean cords that are used in construction and cost $180 for a 50 foot cord. You can usually find these at any good hardware store and they are easily found because they are almost always yellow. The cords I use in these instances are #12 with power indicators built into the receptical end and range in length from 25' to 100'.

Let's not overlook the "distribution" either. You don't need a fancy box to spread power and in the cases I mention above the norm is to use plug strips attached to the ends of the quality extension cables. In my case I have a number of 20A computer grade 1U strips mounted in a small rack mount case. This get's the job done, and it's safe.

For larger venues then I will utilize the site electricians, stage hands and other people who are properly equipped and trained to tap the house circuits.

And even though I have worked with and around high voltages since age 12 (building amplifiers), and even though I can wire a home for 200A, I am still not qualified to distribute AC directly from the venues panel.

Boston and this state adhere to the strictest code and laws in the country. The were written and implimented for a reason.

We as a group are powerless to prevent the OP from following his path to self destruction. We, and especially you have done all that we can within this thread. I can only suggest that if the OP feels that having a distro makes him more valualable in some manner, gives him a certain amount of penashe, then I suggest he re-evaluate his needs. A poor mans distro and yellow extension cords does not indicate a lack of skill. 

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