Cable issue or wiring issue?

Duchey · 08-19-2008, 08:26 PM

Quote:

Originally Posted by 220/221

First, put new batteries in your meter and test it on a known live source.

Turn off ALL of your power and see if the issue goes away.

If it does not, the 120V is coming from an outside source.

If it DOES go away, turn the circuits on and off one at a time and check voltage.

If the voltage reurns on one circuit, you have begun to isolate the problem.

If the voltage returns when ANY of the breakers are turned on, you have isolated the problem to the service.

Tell me if I did this right.
I killed all the power from the breaker box (flipped all the breakers off), then tested it from house ground to the coaxi and still got 120v.
Do I need to cut the main power at the fuse box or is this test good enough?

SD515 · 08-20-2008, 08:22 AM

Quote:

Originally Posted by Duchey

Tell me if I did this right.
I killed all the power from the breaker box (flipped all the breakers off), then tested it from house ground to the coaxi and still got 120v.
Do I need to cut the main power at the fuse box or is this test good enough?

Well...turning off the main is the last one to check..so sure...might as well eliminate all the breakers. Electricity loves to do weird things when things aren't wired correctly. In the meantime, sometime today I hope...I want to do some research on a situation I ran into a couple years ago. Don't know if it'll have any bearing on this, but it involved a customer having an issue, and the cause was a loose neutral in his neighbors house...the current was getting into his house via the municipal underground water pipes, which are grounded and tied together at the street. Get back to ya later.....

jrclen · 08-20-2008, 08:27 AM

Quote:

Originally Posted by Duchey

Cant agree with you more, but I'm still going to kill all the power and do the test cuz I'm a curious bastard.

Ha ha, I can understand that. In that case, be careful.

jrclen · 08-20-2008, 08:37 AM

Quote:

Originally Posted by SD515

Well...turning off the main is the last one to check..so sure...might as well eliminate all the breakers. Electricity loves to do weird things when things aren't wired correctly. In the meantime, sometime today I hope...I want to do some research on a situation I ran into a couple years ago. Don't know if it'll have any bearing on this, but it involved a customer having an issue, and the cause was a loose neutral in his neighbors house...the current was getting into his house via the municipal underground water pipes, which are grounded and tied together at the street. Get back to ya later.....

This problem is well documented. It involves the common practice of multiple services fed from the same transformer.

Here is a link to read about it.

http://ecmweb.com/grounding/electric...uth_grounding/

Duchey · 08-20-2008, 11:58 AM

Quote:

Originally Posted by jrclen

Ha ha, I can understand that. In that case, be careful.

So, do you think that since all the breakers were off and I still got 120v from house ground to coaxi that it's coming from outside? I just want to have as much info for the electrician as I can when he shows up today.

bob22 · 08-20-2008, 01:08 PM

If you are getting the 120v from coax to house ground with breakers off, I'd say highly likely it is the cable system somehow.
Have you checked, with all breakers off, to test one or more outlets in your apt to see if you get any voltage from the ground slot to either the white or black terminals (slots) of your outlets. If so (highly unlikely), then there would be an issue inside your house.
b

theatretch85 · 08-20-2008, 01:25 PM

Quote:

Originally Posted by bob22

If you are getting the 120v from coax to house ground with breakers off, I'd say highly likely it is the cable system somehow.
Have you checked, with all breakers off, to test one or more outlets in your apt to see if you get any voltage from the ground slot to either the white or black terminals (slots) of your outlets. If so (highly unlikely), then there would be an issue inside your house.
b

Just to note, you should not have power from the wide slot to the ground, but you should have power from the smaller slot to ground.

bob22 · 08-20-2008, 03:16 PM

theatretch85:
If all breakers are off, I would think that there should not be any voltage reading between any of the outlet slots assuming no wiring issues or backfeeding through neutral. Where is this thinking wrong?
Thanks,
Bob22

Duchey · 08-20-2008, 03:30 PM

Quote:

Originally Posted by bob22

If you are getting the 120v from coax to house ground with breakers off, I'd say highly likely it is the cable system somehow.
Have you checked, with all breakers off, to test one or more outlets in your apt to see if you get any voltage from the ground slot to either the white or black terminals (slots) of your outlets. If so (highly unlikely), then there would be an issue inside your house.
b

Honestly I don't trust myself enough to go probing wires and stuff. I'll leave that to the electrician.

Here's a better question. IF they do trace the problem to the coaxi, how can I get solid proof and how can I get the cable company to fix it? They've already been out like ten times now and everytime they deny that it's there problem. Don't they have a way of checking this stuff before they put it in?

BigJimmy · 08-20-2008, 04:42 PM

Quote:

Originally Posted by jrclen

This problem is well documented. It involves the common practice of multiple services fed from the same transformer.

Here is a link to read about it.

http://ecmweb.com/grounding/electric...uth_grounding/

Very interesting article, John.

SD515 · 08-20-2008, 06:54 PM

Yes John...that was the article I thought of. Thank you for finding it.

Duchey, you may want to bookmark that article for your electrician to look at if one comes back out.

http://ecmweb.com/grounding/electric...uth_grounding/

As far as proving who's fault it is...I think that will have to be taken care of after the problem has been found.

Duchey · 08-20-2008, 07:51 PM

Quote:

Originally Posted by SD515

Yes John...that was the article I thought of. Thank you for finding it.

Duchey, you may want to bookmark that article for your electrician to look at if one comes back out.

http://ecmweb.com/grounding/electric...uth_grounding/

As far as proving who's fault it is...I think that will have to be taken care of after the problem has been found.

Bookmarked!
Well, I don't know why I didnt think about it before, but I work with some of the best engineers in the world, so I cornered one of them before I left work and told him all the symptoms and testing that's been done thus far.
After half an hour of detailed drawings on a dry erase board he told me that his conclusion would be a floating or open neutral.
So I guess I'll have the guy check that as well.

Oh, forgot to mention. This may have nothing to do with the problem, but when I touch the exposed screws on the top of my refrigerator and the steel of my kitchen sink at the same time I get a little shock. I checked it with the VM and it showed 102v.

SD515 · 08-20-2008, 08:35 PM

MAN...quit touching things!! Especially metal...

I'm going to guess your 'fridge has a 3 prong plug (all do that I know of) and you have a garbage disposal (which has a 3 pronger). It is sounding more and more like a loose/missing neutral somewhere. I wonder if you plugged an extention cord into your neighbors, and test your water meter bonding jumper (don't touch it !!) to both the ground hole and the wide (neutral slot) of the ext cord if you'ld get a reading. Just curiousity on my part.

SD515 · 08-20-2008, 08:39 PM

Duchey, you don't have to do that test on the water meter bond...I was just curious that if you did what the readings would be. That's all.

Duchey · 08-20-2008, 08:51 PM

Quote:

Originally Posted by SD515

Duchey, you don't have to do that test on the water meter bond...I was just curious that if you did what the readings would be. That's all.

Understood. I'm gonna leave this one to the pro, he should be here any second.
I'll be sure to give an update.