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Grounding?

post #1 of 11
8/21/12 at 8:12am
Thread Starter 
I'm sure if this is the right place to post this. Ok I run Sound reinforcement system at our church and the wiring in there is basically useless (brownouts, spikes, dips, you name it). One of things I noticed is that our surge suppressor's ground light is off (yes I know it's useless), now I'm concerned about getting electrocuted. Here's why I'm concerned; Every piece of equipment has a metal chassis, I've already noticed that if I touch the mixer I'll get shocked (static electricity) but another system I've operated that was properly grounded (low impedance) never shocked me. So should I use one of those two to three prong adapter then run a wire to a water piper? Would this provide "protection"?
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post #2 of 11
8/21/12 at 11:22am
Static electricity is generated by you walking around and has nothing to do with the equipment ground.

You should have an electrician check the outlet grounds, or at least pick up a cheap plug-in tester and see what it says. Fixing a bad house (or church) ground should be more than a kludge. You might be ahead to have a new dedicated line run for the sound system.
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post #3 of 11
8/21/12 at 11:51am
Quote:
Originally Posted by kbeam418 View Post

Would this provide "protection"?

Yes, but in the case of a short, it would electrify everything attached to the pipe.

As was stated above, calling in a licensed electrician and having your system looked at is the right thing to do.
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post #4 of 11
8/21/12 at 12:03pm
Thread Starter 
Quote:
Originally Posted by BeeMan458 View Post

Yes, but in the case of a short, it would electrify everything attached to the pipe.
As was stated above, calling in a licensed electrician and having your system looked at is the right thing to do.
I'll be lucky if I can the pastor to have an electrician inspect the wiring! I'm wondering if I can ghetto fix it by running a ground cable of the adapter to the water pipe (the main one).
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post #5 of 11
8/21/12 at 12:13pm
Thread Starter 
Quote:
Originally Posted by BeeMan458 View Post

Yes, but in the case of a short, it would electrify everything attached to the pipe.
As was stated above, calling in a licensed electrician and having your system looked at is the right thing to do.
I know that it's dangerous to ground something to a water pipe but the **** up (pardon my language) who did the wiring attached the earth ground and neutral ground to the water pipe (I know because the sound system is above the main pipe, so the least of my worries is grounding the sound system to the pipe. The ground wire they used looks like cheap 24 AWG speaker wire. As far as running a dedicated line (you mean circuit right?) we have a dedicated 15-amp line running to two outlets (the sound system is plugged into one of them) but the pastor would never let anyone run a ground cable.
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post #6 of 11
8/21/12 at 12:17pm
Quote:
Originally Posted by kbeam418 View Post

I'll be lucky if I can the pastor to have an electrician inspect the wiring! I'm wondering if I can ghetto fix it by running a ground cable of the adapter to the water pipe (the main one).

P.M. sent.
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post #7 of 11
8/21/12 at 12:24pm
Thread Starter 
Quote:
Originally Posted by DonH50 View Post

Static electricity is generated by you walking around and has nothing to do with the equipment ground.
You should have an electrician check the outlet grounds, or at least pick up a cheap plug-in tester and see what it says. Fixing a bad house (or church) ground should be more than a kludge. You might be ahead to have a new dedicated line run for the sound system.
Yes but the electricity should flow to the ground. My proof of this is I have ran systems that ran on good wiring and I could rub a balloon on my hair and touch the mixer and I wouldn't get shocked. As far as running a dedicated line we already have a 15-amp breaker powering it but the wiring was installed by someone who doesn't know what he's doing. Our building was built in 1980 yet we don't even have 200-amps going in! The actual ground (the one that comes from city) is grounded to water pipe using 24AWG wiring, and when the HVAC system kicks on the voltage dips below 90v.
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post #8 of 11
8/21/12 at 12:42pm
Static electricity flows between potential differences and it does not matter if ground or not. You can get shocked touching a metal doorknob in a wooden door and few of them are grounded... The argument could as well be made that you should get a worse shock with a solid ground due to the lower impedance.

The dedicated lines (circuits, runs, whatever you prefer) should have included a good ground return (neutral) and safety ground. If the electrician did not do this he violated code.

Does the voltage dip when measured at the service (panel, breaker)? If so your main feed is inadequate (or something is wrong in the HVAC, possible but unlikely). The ground return has nothing to do with voltage sag (unless it is seriously miswired; the ground is a safety ground and should not in general carry large current). It may be as simple to fix as putting the HVAC on one side and sound system circuit on the other leg of the incoming feed.

You might consider putting the low-level stuff on an APC (or whatever) UPS to protect from power glitches. The power amps will probably ride out short ones and it would cost a fortune to gte UPS' big enough.

No way would I risk myself and a lawsuit for the church (and me) by doing it myself. Grounding the sound system, maybe, but not for the electrical circuit. I do not know code in your area, but am surprised a 24 AWG service ground passes...

Seriously, you really need to have a licensed electrician deal with this. Anything else is a huge liability for both you and the church. It sounds like you have already decided to jury-rig it so why ask?

Whatever - Don
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post #9 of 11
8/21/12 at 1:40pm
Thread Starter 
Quote:
Originally Posted by DonH50 View Post

Static electricity flows between potential differences and it does not matter if ground or not. You can get shocked touching a metal doorknob in a wooden door and few of them are grounded... The argument could as well be made that you should get a worse shock with a solid ground due to the lower impedance.
The dedicated lines (circuits, runs, whatever you prefer) should have included a good ground return (neutral) and safety ground. If the electrician did not do this he violated code.
Does the voltage dip when measured at the service (panel, breaker)? If so your main feed is inadequate (or something is wrong in the HVAC, possible but unlikely). The ground return has nothing to do with voltage sag (unless it is seriously miswired; the ground is a safety ground and should not in general carry large current). It may be as simple to fix as putting the HVAC on one side and sound system circuit on the other leg of the incoming feed.
You might consider putting the low-level stuff on an APC (or whatever) UPS to protect from power glitches. The power amps will probably ride out short ones and it would cost a fortune to gte UPS' big enough.
No way would I risk myself and a lawsuit for the church (and me) by doing it myself. Grounding the sound system, maybe, but not for the electrical circuit. I do not know code in your area, but am surprised a 24 AWG service ground passes...
Seriously, you really need to have a licensed electrician deal with this. Anything else is a huge liability for both you and the church. It sounds like you have already decided to jury-rig it so why ask?
Whatever - Don
Thanks for explaining the static electricity for me! The "electrician" was someone in the family who knew how to wire the church but simply didn't know how to do it properly. The voltage sags on our end. It's against code to use anything less 8 AWG wiring for ground, don't ask me how it passed inspection. I'm considering getting a Optiups 3000VA ups. From what the other post have said (and you) I won't jury rig it unless we start having ground loop problems. If we start having ground loop problems I'll pay my uncle (he's licensed and does great work)) to just ground that circuit (has to be cheap).
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post #10 of 11
8/21/12 at 4:00pm
No problem.

I (and many others) can tell all sorts of tales of woe when wiring was done improperly to save a few bucks. My worst-case example is a guy who added a 220 V dryer outlet that ended up causing a fire due to some really stupid installation errors. The insurance company did not pay as it was not properly installed and inspected. That's a heavy price to pay!

I used to have my license but no longer. Now, I pay someone who does or do it myself and have it inspected, making sure I have a record. I would not wire a commercial place unless forced and would still make sure it was properly inspected. The inspectors I have dealt with would not have passed that ground...

p.s. If you have to pay, donate to the church and have the church pay. That way you'll get a tax write-off. wink.gif
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post #11 of 11
8/21/12 at 6:57pm
Thread Starter 
Quote:
Originally Posted by DonH50 View Post

No problem.
I (and many others) can tell all sorts of tales of woe when wiring was done improperly to save a few bucks. My worst-case example is a guy who added a 220 V dryer outlet that ended up causing a fire due to some really stupid installation errors. The insurance company did not pay as it was not properly installed and inspected. That's a heavy price to pay!
I used to have my license but no longer. Now, I pay someone who does or do it myself and have it inspected, making sure I have a record. I would not wire a commercial place unless forced and would still make sure it was properly inspected. The inspectors I have dealt with would not have passed that ground...
p.s. If you have to pay, donate to the church and have the church pay. That way you'll get a tax write-off. wink.gif
I really don't understand what the person who wired our building was thinking! I really hate when people use a handy-man they know just because it's cheaper. I would not be surprised if we end in one of those horror stories.
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