Electrician's F-Up Fries Gear - ARRGH!

jaywa · #1 06-27-2011, 07:48 AM

Was going to put this in the Gig Stories forum but there's really nothing humerous about it so it's going here instead...

Two days ago, setting up for a street dance and we've got our P.A. up and running the break music, everything good. All the sudden there's there's some really bad noises coming out of the system and when we power everything down there's that unmistakable smell of burnt-up electrical gear.

Gear put out of commission included a 4,000-watt Crown power amp as well as at least three of our IEM sending units, our guitarist's POD and his vintage Fender combo amp.

After at least an hour's worth of troubleshooting we took apart an electrical adapter we were using for the first time and found it had been miswired internally, sending hot current down a neutral line. The guy who built the adapter is an electrician we've used before (he built our distro) and he knows what he's doing but this was a pretty major f**k-up by anyone's standards.

Today the BL is doing inventory on our gear to assess the damage. If we're lucky and the only things that blew were AC converter packs and fuses, we may escape for $100 or less. OTOH if the components themselves are fried, obviously the final tab will be much higher. Thankfully we had enough backup gear we could still go on with the show, but it caused a whole lot of unnecessary stress and expense.

Not sure there's a moral to this story or if this is just a rant. You wouldn't think we shouldn't have had to take the adapter apart and verify everything was correct before we used it, but apparently we should have.

**BullHorn** · #2 06-27-2011, 08:22 AM

Moral of the store: Bring your own electricity? :x

That sucks man, I hope get to escape it...

Vinny D · #3 06-27-2011, 08:23 AM

Quote:

Originally Posted by jaywa

After at least an hour's worth of troubleshooting we took apart an electrical adapter we were using for the first time and found it had been miswired internally, sending hot current down a neutral line. The guy who built the adapter is an electrician we've used before (he built our distro) and he knows what he's doing but this was a pretty major f**k-up by anyone's standards.

.

So was there just the hot and the neutral switched?
Or was there 120v being delivered on the hot & neutral?
And what is this adapter that was made?

Just curious as I am trying to understand what happened.

TinIndian · #4 06-27-2011, 08:25 AM

Wow! I guess anyone can make a mistake, but that sucks. Good Luck!

jaywa · #5 06-27-2011, 09:00 AM

Quote:

Originally Posted by Vinny D

So was there just the hot and the neutral switched?
Or was there 120v being delivered on the hot & neutral?
And what is this adapter that was made?

Just curious as I am trying to understand what happened.

I will try to answer these questions but I'm possibly the least techie guy in the entire band. The last question first:

We have a distro that rides in a stand-up Anvil-style case with the circuit breaker box and 5 or 6 120v quad boxes all hard-wired in. There is also a long heavy master cord wrapped up on a drum, which terminates in a four-prong "dryer" type plug for 220. Since we still frequently encounter 220 outlets that are three prong (especially in the summer when we do a lot of small-town street dances), this guy made us an adapter with a male three prong plug and a female 4-prong outlet. So the 3-prong gets plugged into the 220 outlet and then the 4-prong from our distro gets plugged into the outlet on the adapter.

So was there just the hot and the neutral switched?
Or was there 120v being delivered on the hot & neutral?

I don't know which of the two scenarios you describe is what happened, but the adapter is where they traced the problem back to. Based on the chatter I heard I think it was the 2nd situation but I couldn't swear to that. Sorry I can't be more specific... I was just watching this all unfold from a distance cause everyone else was stressing plenty and I figured I couldn't contribute anything to the solution so I just stayed out of the way.

Thankfully none of my personal gear was damaged but our show still suffered because we had to go without one of our sub cabinets due to the power amp going down.

modulusman · #6 06-27-2011, 09:02 AM

This is why I always use an outlet tester at any place I havn't played before. Jaywa sorry to hear about the accident hopefully it isn't too expensive.

jaywa · #7 06-27-2011, 09:09 AM

Quote:

Originally Posted by modulusman

This is why I always use an outlet tester at any place I havn't played before. Jaywa sorry to hear about the accident hopefully it isn't too expensive.

Yes, and we have made this same resolution after this last weekend's incident.

We carry an outlet tester with us, but didn't think to test the adapter before using it the first time.

Vinny D · #8 06-27-2011, 10:08 AM

Quote:

Originally Posted by jaywa

Or was there 120v being delivered on the hot & neutral?[/i]

I don't know which of the two scenarios you describe is what happened, but the adapter is where they traced the problem back to. Based on the chatter I heard I think it was the 2nd situation but I couldn't swear to that. .

It seems like this was the case after your explanation, sucks either way though...

jaywa · #9 06-27-2011, 10:58 AM

Yeah... I suppose if the repair tab gets too high we could go after the electrician to pay for it but I have a feeling we're gonna just wind up eating it.

Never_grew_up · #10 06-27-2011, 01:19 PM

240 3 prong to 4 prong won't work. 3 prong is 2 hots + ground. 4 prong is 2 hots + neutral + ground. No neutral means no single phase 120v.

jaywa · #11 06-27-2011, 01:25 PM

Quote:

Originally Posted by Never_grew_up

240 3 prong to 4 prong won't work. 3 prong is 2 hots + ground. 4 prong is 2 hots + neutral + ground. No neutral means no single phase 120v.

So are you saying we need to get rid of that adapter because there's no way it can be wired to work?

Clark Dark · #12 06-27-2011, 04:06 PM

Quote:

Originally Posted by jaywa

Yeah... I suppose if the repair tab gets too high we could go after the electrician to pay for it but I have a feeling we're gonna just wind up eating it.

who knows, the electrician may be bonded and insured in which case you may be made whole again without any problems.

jaywa · #13 06-28-2011, 07:42 AM

Quote:

Originally Posted by Clark Dark

who knows, the electrician may be bonded and insured in which case you may be made whole again without any problems.

Well, the electrician is a friend of our guitarist (our other guitarist, not the one who lost his gear), and our guitarist was really pissed this happened. And he's usually pretty pro-active about this stuff so we'll see if he takes it any further.

WalterBush · #14 06-28-2011, 07:53 AM

Quote:

Originally Posted by Never_grew_up

240 3 prong to 4 prong won't work. 3 prong is 2 hots + ground. 4 prong is 2 hots + neutral + ground. No neutral means no single phase 120v.

That's not accurate; depending on the internal wiring of the distro box, they could very easily get single phase 120 from 240 with no existing neutral wire. Neutral and ground are bonded at any venue's distribution, anyway. It's very common for installers and electricians to bond the neutral and ground in a four-wire setup to fit in an existing three-prong 240 outlet.

Of course, in this case, it obviously didn't work. But anything posted on the internet without details on the electrical will be pure speculation. The bottom line is, power should be tested, always. Especially when using new distribution equipment, if for no other reason that even the best built distribution box on the planet will not be able to do its job if the venue has faulty wiring or a generator isn't hooked up properly.

jaywa · #15 06-28-2011, 08:19 AM

Basically I need to know if I need to tell my band to never use that F***ing adapter again, or if it can still be made to work.

In the past we've just traveled with a "pigtail" 3-prong outlet that we wire-in when we encounter those situations. I'm really thinking we need to just go back to that and this is a case of fixing something that wasn't broken... and breaking more stuff in the process.

bassmeknik · #16 06-28-2011, 09:48 AM

Quote:

Originally Posted by WalterBush

That's not accurate; depending on the internal wiring of the distro box, they could very easily get single phase 120 from 240 with no existing neutral wire. Neutral and ground are bonded at any venue's distribution, anyway. It's very common for installers and electricians to bond the neutral and ground in a four-wire setup to fit in an existing three-prong 240 outlet.

Of course, in this case, it obviously didn't work. But anything posted on the internet without details on the electrical will be pure speculation. The bottom line is, power should be tested, always. Especially when using new distribution equipment, if for no other reason that even the best built distribution box on the planet will not be able to do its job if the venue has faulty wiring or a generator isn't hooked up properly.

1+ any new power adapter should have been tested, and IMO tested by the builder....

I am that guy in most of the bands I have worked in. I am trained but not licensed. I am a lifer diy electrical hobbyist that seldom has had the money to accomplish my musical goals. This has driven my interest to learn and my desire to build items that improve the sound and saleability of my band(s). I would have tested it at home immediately after completion to verify safe and proper operation. A volt/ohm meter (DVOM) is all that is required.

That said when ever I am faced with using a facilities power for the first time I want to check out those facilities (panel box, etc.) and a new custom adapter like you mentioned I would have to verify proper polarity to ensure the safety of myself and fellow performers. Translated I would be there with a meter making SURE it was right...

A cheap meter will do the necessary tests and they are easy, quick and safe to perform if you follow proper testing procedures. learn learn learn

bassmeknik · #17 06-28-2011, 09:24 PM

Quote:

Originally Posted by jaywa

Basically I need to know if I need to tell my band to never use that F***ing adapter again, or if it can still be made to work.

Most likely two of the wires (two IMPORTANT wires) are simply switched by mistake, find the mistake and correct it and you should be good to go.

bassmeknik · #18 06-28-2011, 09:25 PM

just be sure to test it at the venue with a volt meter prior to first use...

bassmeknik · #19 06-28-2011, 11:05 PM

thinking about this I see you are in the US so I assume this adapter has standard 110 volt power receptacles??? If so go to Home Depot, Lowes, or your local builders/electrical supply and get an outlet tester for about $10 (your electrician probably owns one) and test EVERY receptacle you use from now on, the life you save or injury you prevent could be your own...........

http://www.homedepot.com/Electrical/...atalogId=10053

To use this just plug in and look for the proper indicator lights to be on, takes 2 seconds to use. WORTH IT

btbraden · #20 06-28-2011, 11:18 PM

Fwiw u should never use a bare ground wire in a 3 wire 240 plug as a neutral even if does somehow give u 120 this could be very dangerous as u don't know if that ground does make it all the way back to the main service or not, if it doesn't u or someone else had the potential to be the ground or path of least resistance to ground, just wanted to put that out there as I am a electrician and don't want to see any one or anything hurt or destroyed
Brian