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brickbob · Jun 28, 2007, 10:36 PM

I have been reading threads here but want to be sure I understand since electricity is potentially so dangerous. I have an old house. My main breaker box below the meter has two large hot legs and an uninsulated neutral. There is no ground terminal. There is no ground rod. I'm sure something is connected to a water pipe somewhere in the attic but just before my waterline enters the house there is a PVC repair. I have a metal lightstand on the patio that will shock you if you are barefoot and it is damp out. I put my voltmeter between a metal lightswitch box and my chainlink fence and found around 60 volts. Shouldn't I have a ground rod installed at my main breaker and don't I have to connect it to the neutral since there is no equipment ground?
Thanks, Robert

PS The guy with the electric shower is freaking me out!:eek:

tkrussell · Jun 29, 2007, 07:34 AM

Without getting into all the variables of grounding, and considering the fact that you have a serious ground fault issue, I need to suggest that you have an electrician look at your system ASAP, first to find the fault causing the exposed shock hazard, and two, correct any grounding issues.

What you can and should do is to trace and shut off the circuit breaker that is feeding the switchbox that is energized.

brickbob · Jun 29, 2007, 08:00 AM

I intend to get an electrician with the next paycheck. Meanwhile, is it a bad idea to install a ground rod at my main breaker connecting to the neutral? Thanks again, Robert

tkrussell · Jun 29, 2007, 12:44 PM

Does the panel have the first Main breaker in it? If so, then there can be a grounding wire to a rod connected there. There may be a grounding wire at the meter.

Keep in mind, there is already, or should be, a grounding wire at the utility transformer.This grounding wire to a rod is not the reason there is a ground fault at the switch, and while installing one at the enclosure that contains the Main Breaker will not hurt, it will not solve the fault problem.

Be sure to have the water line with the PVC repair looked at to determine if it needs to be or is capable to be used as the primary grounding electrode, or just bonded.

Have you shut off the circuit with the ground fault?

brickbob · Jun 29, 2007, 03:04 PM

Yes, it is shut off. No one lives in the house yet. Just me and a dog when I'm working on it. I'm in Louisiana and sometimes when it has rained the lights will not come on in the garage. The garage is on that circuit. I assume I am looking for a wire going to ground somewhere. It may be a week or so before the electrician gets here. I don't guess there is any magic trick to locating a ground fault. I have wondered if installing a GFCI at various places along the circuit would isolate and narrow down the search? Thanks for your help. I have read a number of your posts. Not only do you know your stuff, but you are quite concerned about us do it yourselfers.
Robert

tkrussell · Jun 29, 2007, 06:27 PM

Thank you for the kind words. And yes I am concerned about anyone that works with electricity. Even experienced electrical workers get hurt, we have lost several brothers by this source of power. Sometimes we pros get cocky, and we only get one chance.I have had a few close calls myself, sometimes I think I am living on borrowed time.

Current across the heart, hand to hand, hand to foot, etc 6-8 millamps or more across the heart is lethal. The wife wonders if I have a heart, having had so many serious shocks. The one that was the 277 volt wire touching my head and went through both hands that were grounded by metal was shall we say "illuminating".

Correct, looking for this fault may be difficult to locate , even for a pro. Best to leave it to a pro and don't try to locate yourself. Just leave it off, have the short located and repaired, and ask that the entire grounding system be inspected and brought up to code.

Be sure the electrician applies for a permit and has his work inspected if that applies in your area.

brickbob · Jun 30, 2007, 02:44 PM

Ok, here is what I did today. There is an old unused ground rod sticking out of the driveway on the opposite side of the house from the main box. I hooked a spool of wire to the rod and went around with my volt meter checking anything metal. 45V to 50V on the entire circuit. 90V on the frame of the patio quartz light! I took the light apart and found the wiring burned. Repaired that and detected 45V to 50V when I plugged it back in. As I said before, the garage is on the offending circuit. I shut off the circuit then opened up the light switch inside the back door. Turned the power back on and when I pulled on a greenie the garage lights went off. The garage was powered from a splice inside that wall switch. That doesn't sound like code. With the garage disconnected there was 2V to ground. I reattached the garage to another circuit bypassing 20 feet or so of the original line. In the garage I have 10 V from switch box to ground. At the back door I still have 2V.
Is this progress?

BTW, all this took 6 hours. I have probably walked a mile just between the breaker and the back door.

Thanks again, Robert the bricklayer, not electrician.:D

tkrussell · Jun 30, 2007, 04:09 PM

Actually sounds like your doing OK. The 2 volts is OK, the 10 is questionable, may or may not be just a normal ground fault, or stray or induce voltage. Is there a certain breaker than makes the 10 volts go to zero?

brickbob · Jun 30, 2007, 05:14 PM

Yes, the 220 breaker at the main box. I tapped into one leg of the dryer outlet to get some light in there.

On the subject of the ground rod... I know I have seen some sort of ground on a water pipe in the attic. However, the water line is interrupted at the corner of the house with a PVC repair. Does grounding the neutral at the main box require that the neutral be attached to the box? Remember, no ground bar. Am I making something of nothing concerning the non-existant ground rod. The ground at the utility pole does appear to be
Intact.

One other question. Could a ground fault like we have been talking about make your electric bill go up?

Thanks again, Robert The Rabid LSU Tiger Fan

tkrussell · Jul 1, 2007, 01:07 PM

This is why an electrician needs to review the grounding system. "Grounding" to a utility water system is not allowed beyond 5 feet of the point of entry into the building.

"Bonding" the metal water system in the building must be done, and can be connected anywhere in the building.

As you noted, the utility pole has a "ground", which is grounding the grounded conductor. Therefore your neutral is grounded. It does need an additional connection to ground, which must be the utility water system if this exits, and must have one additional ground rod.

If the water system is not a utility, then there must be at least one ground rod connected to the neutral at the box that contains the main disconnect.

Since there is no separate ground bar in your panelboard ,and the main breaker is in this box, there is no need for a separate ground bar, the neutral bar acts as both, as they must be connected here together.

This neutral bar is where a grounding electrode conductor to either the utuility water and/or ground rod can connect. The neutral is also allowed to be grounded at the meter.

As I mentioned there are several variables to grounding and bonding. Each has it's own purpose, and can be done in various methods. There is on one answer that covers everyone. There are certain things that must be done, and can be done in various methods, and there are certain things that may be done, again in various methods.

No a ground fault does not affect the utility bill.

brickbob · Jul 1, 2007, 01:26 PM

Thanks again. Got to leave town for a couple of weeks. This is one trouble I have had in meeting the electrician. I work out of town 170 to 200 days a year!

Thanks again, Robert

LSU National Champs this year!