Power issue at club. Plugging PA into main power box?

[TIMKEYS]

Maybe it was originally installed correctly, and pieces were taken off. Hard to tell. Don't know if the neutral is connected to an isolated lug or if it's bonded directly to ground from the photo.

 

 

It prolly would not be all that hard to figure out if you could really get a good look at it. I used to jump into all kinds of power boxes when I had the insulation company. You tapped in with rubber shielded clips. Never was much of a problem but always kept you on your toes.

[Keyrick]

It prolly would not be all that hard to figure out if you could really get a good look at it. I used to jump into all kinds of power boxes when I had the insulation company. You tapped in with rubber shielded clips. Never was much of a problem but always kept you on your toes.

 

 

It is really not a good idea nor is it safe to tap into that disconnect with any type of clip. There does not appear to be any EGC (Ground) connection, unless it is that tape wrapped conductor, who knows. And what would you tap into it with? An extension cord connected to a power strip? So many folks think that the neutral and ground are the same, and they're not.

 

It is too bad too, as for not a lot of money, the club owner could have a proper sub-panel installed with breakers feeding 6 or 8 5-20s. Less than a grand easily. I hope no one ever gets hurt by doing what you suggest.

 

Rick

[RoadRanger]

It prolly would not be all that hard to figure out if you could really get a good look at it. I used to jump into all kinds of power boxes when I had the insulation company. You tapped in with rubber shielded clips. Never was much of a problem but always kept you on your toes.

I think this falls under the classification of "crazy $%^& we did back in the bad old days that is best kept to ourselves" . Seriously we have folks stumbling upon this forum that don't know what an active crossover is or what is the best amplifier to drive a powered speaker and barely know which end of the mic to scream into . Let's not kill anybody here, eh?

[W. M. Hellinger]

I think this falls under the classification of "crazy $%^& we did back in the bad old days that is best kept to ourselves"

Ya mean like prop a ladder on the top of a box truck to gain access to vise-grip clamp welding cables for the distro onto the nuts on a transformer ???

Edit: now that I think about that stunt... as I recall: The box truck was just about 6" too short even with the propped up ladder, so we hoisted the ass-end of the box truck up with a fork lift... me on top directing the operation.

[RoadRanger]

"Momma, don't let your babies grow up to be cowboys..."

[scarecrowbob]

"me on top directing the operation."

 

Somebody got to be in charge, you know.

 

I do stupid stuff all the time. I've got melted DMM probes to prove it. But I have lived long enough to [not] post about it.

 

I was on a shoot in Jamaica and took my legs on a tour. It was neat to see Edison female plugs with bare wires inserted. I was impressed, at least.

 

Really, this stuff can kill you, but so can crossing the street. I wouldn't mess with any of it, but "the people will survive, in their environment" ( http://www.youtube.com/watch?v=qNHXvoGfEFE ).

[hobbenator]

Take the gig, then enjoy all the drugs the hospital gives you, and then sue the club, the building owner, the city building inspector, and any manufacturer in that power box.

[agedhorse]

"Momma, don't let your babies grow up to be cowboys..."

We have a saying when we are out on the road with hoe (horses) show... "Mama don't let your cowboys grow up to be crybabies...

[agedhorse]

It prolly would not be all that hard to figure out if you could really get a good look at it. I used to jump into all kinds of power boxes when I had the insulation company. You tapped in with rubber shielded clips. Never was much of a problem but always kept you on your toes.

 

 

Illegal and not safe in a public occupancy application. Who cares what you do to yourself, but when other folks are concerned, the codes are there for a very good reason.

 

there are also plenty of folks who ment well who are now disabled or dead because of dumb-ass stuff like this. The real dumb-asses are the most obvious because they are the most burned and disfigured when they discover that what their dumb asses thought was 120 volts really turned out to be 277/480. Guys, it happens more often than you might think. I get a couple of (electrical and plant engineering) trade magazines that feature forensic articles each issue, and the stuff they come up with are truely shocking (in a figurative and literal way).

[RoadRanger]

I get a couple of (electrical and plant engineering) trade magazines that feature forensic articles each issue, and the stuff they come up with are truely shocking (in a figurative and literal way).

And these folks are often "electricians" who should know better . You gotta ask yourself if you're feelin' lucky today - "Well, are yah punk?"

[agedhorse]

And these folks are often "electricians" who should know better . You gotta ask yourself if you're feelin' lucky today - "Well, are yah punk?"

Usually the death and destruction is more spectacular with non-electricians and wannabes.

[Don Burke]

While this setup is a little unsettling, I could figure out a way to make this work safely, assuming the rest of the wiring was acceptable.

The deal breaker is what the rest of the wiring must be like in order to make this the best option.

[RoadRanger]

Usually the death and destruction is more spectacular with non-electricians and wannabes.

Dunno, an electrician at one of my jobs cut through all three conductors of a live 440V three phase circuit once and vaporized half the blades of the shears - that'll teach him to trust somebody else's assurance that the circuit was switched off!

[agedhorse]

While this setup is a little unsettling, I could figure out a way to make this work safely, assuming the rest of the wiring was acceptable. The deal breaker is what the rest of the wiring must be like in order to make this the best option.

 

 

It's not unsettling, it's unsafe. There is a distinct difference. Without the proper repairs, it's not safe period.

[W. M. Hellinger]

While this setup is a little unsettling, I could figure out a way to make this work safely, assuming the rest of the wiring was acceptable. The deal breaker is what the rest of the wiring must be like in order to make this the best option.

 

Make what the best option?

 

Your wording is a bit confusing. If you personally are capable of figuring out a way to make the shown disconnect work safely, then there's no doubt in my mind that you'd also have the chops and know the necessity of confirming the viability status of the rest of the associated wiring involved with that disconnect circuit yourself. IOW: If you're capable of the feasibility study & rework of the disconnect box, you'd be capable of a feasibility study of the whole circuit... and would have done that as just part of the process of determining that you could figure out a way to make it work safely for your needs.

 

So is your question with working over the disconnect circuit so it's up to snuff? Or deciding if it's cost effective to habilitate the disconnect circuit so it's up to snuff vs. pulling power elsewhere... which begs the question of what else is available in the venue and how does it stack up to the disconnet box shown in the picture? If the other available power options in the venue are comparable to the disconnect, and assuming you still want to play that venue... hiring a licensed contractor to bring the disconnect circuit up to snuff and configure it to hook-up to your distro (if you have a distro and if you need what appears to be 50A, or possibly 60A of 220v power capacity as shown in the disconnect)... then yes, maybe hiring a licensed contractor to work the disconnect service over might be your most cost effective solution. Maybe the venue would even consider cost sharing if the end result was in their better interest (doubtful though, cause generally if it ain't broke, why fix it? "Bands play here all the time and make the available power situation work just fine, so what's the problem?").

[W. M. Hellinger]

It's not unsettling, it's unsafe. There is a distinct difference. Without the proper repairs, it's not safe period.

 

Yes. "Unsettling" is being told by an airline stewardess that your seat cushion can be used as a life preserver in the event of a "water landing". It's unsettling to picture needing to use that seat cushion as a floatation device sometime shortly after the end of the flight.

 

Unsafe is looking out the airplane window and noticing a large pool of jet fuel forming under the airplane while it's boarding passengers.

[W. M. Hellinger]

So... how big is this venue? What level of acts do they routinely book in?

The reason I ask is that a disconnect as possibly the only real available stage power is somewhat "big time"... around here anyway.

[Don Burke]

Make what the best option? Your wording is a bit confusing. If you personally are capable of figuring out a way to make the shown disconnect work safely, then there's no doubt in my mind that you'd also have the chops and know the necessity of confirming the viability status of the rest of the associated wiring involved with that disconnect circuit yourself. IOW: If you're capable of the feasibility study & rework of the disconnect box, you'd be capable of a feasibility study of the whole circuit... and would have done that as just part of the process of determining that you could figure out a way to make it work safely for your needs. So is your question with working over the disconnect circuit so it's up to snuff? Or deciding if it's cost effective to habilitate the disconnect circuit so it's up to snuff vs. pulling power elsewhere... which begs the question of what else is available in the venue and how does it stack up to the disconnet box shown in the picture? If the other available power options in the venue are comparable to the disconnect, and assuming you still want to play that venue... hiring a licensed contractor to bring the disconnect circuit up to snuff and configure it to hook-up to your distro (if you have a distro and if you need what appears to be 50A, or possibly 60A of 220v power capacity as shown in the disconnect)... then yes, maybe hiring a licensed contractor to work the disconnect service over might be your most cost effective solution. Maybe the venue would even consider cost sharing if the end result was in their better interest (doubtful though, cause generally if it ain't broke, why fix it? "Bands play here all the time and make the available power situation work just fine, so what's the problem?").

 

 

That disconnect could probably be brought up to code very quickly with only a few parts, a bit longer if the ground needs to be replaced. I would have to see the local electrical code. If it were my call, the ground wire would be the same size as the neutral even if the local code allowed the size we are seeing. (I am guessing 12 or 14 is what that wire wrapped with tape is.) That part is not something I would go drama queen over.

 

There is a big caveat regarding what is upstream of that box, which I might indeed go drama queen over and storm out of the place. I strongly suspect that would be the case.

 

I find it hard to believe very many bands need 220 at 50 amps. I would be very surprised if any that do would be asking about it on the web.

 

My guess is that the disconnect we are seeing is something that was bouncing around someone's garage as a leftover from an HVAC upgrade.

 

To state it plainly, that box can almost certainly be fixed, but I doubt the upstream wiring is any better than that, so after a short inspection, I would probably be gone.

 

I think I can make a pretty good guess at what the kitchen wiring looks like.

 

By best option I meant that all of the other ways of getting power to a PA have been deemed worse than what we are looking at. That is what concerns me more than anything I can see in that box.

[W. M. Hellinger]

By best option I meant that all of the other ways of getting power to a PA have been deemed worse than what we are looking at. That is what concerns me more than anything I can see in that box.

 

My sincere apologies: I confused your post with the OP-er. (it looks like I need to have a chat with my fact checker).

 

Never-mind the specifics of my post toward your post, but the generalities probably apply.

[agedhorse]

The NEC allows grounding conductor size reductions based purely on the ability to adequately clear fault currents and open the OCP without allowing a significant voltage rise above ground. This conductor derating is standard procedure and completely safe. Depending on the grounding scheme, it may (though not at all guaranteed) reduce noise slightly with a heavier ground (does not apply in an isolated ground installation) only because it reduces the voltage drop (potential) generated by leakage currents through a conventional grounding system.

Note that there are also high impedance grounding systems that use an unbonded (actually loosely bonded) ground and this is always accompanied by a RCCB that monitors the current in the ground and trips the breaker in the event that the leakage current it greater than normal. The reason for this kind of system is to limit the fault damage in very high capacity installations. It's unlikely that you will ever see one in your life, but it's important to understand how grounding systems work.

[Craig Vecchione]

 

That disconnect could probably be brought up to code very quickly with only a few parts, a bit longer if the ground needs to be replaced. I would have to see the local electrical code. If it were my call, the ground wire would be the same size as the neutral even if the local code allowed the size we are seeing. (I am guessing 12 or 14 is what that wire wrapped with tape is.) That part is not something I would go drama queen over. There is a big caveat regarding what is upstream of that box, which I might indeed go drama queen over and storm out of the place. I strongly suspect that would be the case. I find it hard to believe very many bands need 220 at 50 amps. I would be very surprised if any that do would be asking about it on the web. My guess is that the disconnect we are seeing is something that was bouncing around someone's garage as a leftover from an HVAC upgrade. To state it plainly, that box can almost certainly be fixed, but I doubt the upstream wiring is any better than that, so after a short inspection, I would probably be gone. I think I can make a pretty good guess at what the kitchen wiring looks like. By best option I meant that all of the other ways of getting power to a PA have been deemed worse than what we are looking at. That is what concerns me more than anything I can see in that box.

 

 

If the local code is based upon any remotely recent NEC model, then there's no way to bring this to code as a 120/240 switchbox. It's a 240v-only box. The neutral is presently connected to the grounding connection/bus. There is no provision in the box for a separate bus bar, so you can't create a separate floating neutral bus in there. Even if the neutral and ground are properly wired upstream, you have to replace this box entirely. The irony is that all that's required here is a receptacle of the right size and type for the feeder OCP and wiring.

[jasps]

FWIW, Even if a licensed electrician installed/modified the box--it doesn't mean anything. IME, some electricians will listen, nod head, and go about taking direction from whomever is paying. They are not necessarily concerned with the design or operation of the final contracted "power system."

[agedhorse]

If the local code is based upon any remotely recent NEC model, then there's no way to bring this to code as a 120/240 switchbox. It's a 240v-only box. The neutral is presently connected to the grounding connection/bus. There is no provision in the box for a separate bus bar, so you can't create a separate floating neutral bus in there. Even if the neutral and ground are properly wired upstream, you have to replace this box entirely. The irony is that all that's required here is a receptacle of the right size and type for the feeder OCP and wiring.

 

 

I agree the way it looks now. It looks like the floating neutral assy may have existed where the neutral is connected and bonded to ground, there were 2 holes in the metal plate that may have been for mounting the neutral assy. That would be something the manufacturer would have to answer.

[Craig Vecchione]

 

FWIW, Even if a licensed electrician installed/modified the box--it doesn't mean anything. IME, some electricians will listen, nod head, and go about taking direction from whomever is paying. They are not necessarily concerned with the design or operation of the final contracted "power system."

 

 

Very true. It all depends whether they have to answer for the repercussions of a trajedy. If the work is documented, they will find themselves in a world 'o hurtin', but if cash changes hands under the table, anything can happen.

[Craig Vecchione]

 

I agree the way it looks now. It looks like the floating neutral assy may have existed where the neutral is connected and bonded to ground, there were 2 holes in the metal plate that may have been for mounting the neutral assy. That would be something the manufacturer would have to answer.

 

 

Yep, the box looked as if it was raped. I see what appears to be a brass screw on that plate as well...