Another GFCI circuit breaker question

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I was just having the same thought Jason, if the white and ground are connected back at the breaker box then the problem is the opposite of what we have been saying since ground and neutral are tied together at your service entrance. If the white is disconnected from the breaker box for these tests then the problem is leakage to ground in the wiring or the fixture.
 
Jason, when I disconnected the wire from the fixture (so its open at both ends nothing connected) I read 0.F.L on each one. No longer do I see the reading from before. Should I pull each fixture and test the wire from and to each one? Can I test the fixture somehow? it has a white and black wire on it...

also 0.F.L. is the same thing my meter reads when it is not connected to anything... also same for overload (sounds odd) but I know for sure with nothing connected I see it... so I no longer get a reading on that wire... its just open. also continuity does not beep so no short to each wire as well.

thanks...
 
Then that fixture is bad (or perhaps another one that is disconnected recently if there is such a one). Any other fixtures that are still connected are alright.

Each fixture should be grounded as well as having two power wires, i.e. green/bare, white, and black wires connected to each fixture. You can test the fixtures by measuring resistance between where ground connects and where white connects.
 
Ok I think I follow now. I should see no resistance when the wire is fully disconnected or 0.f.l. In my case as well. If the wire is connected to the fixture should it also be no resistance with no bulb or what reaction there? I guess I need to be sure I am giving good feedback to you. As I see it the black was showing ofl but the white had a reading... Guessing you want me to disconnect each light till I see the white go of as well?

Also if I check the fixture (ground to white and ground to black... Should I expect ofl or resistance ?
 
I was able to just come back to this after being away from a computer all day. I think the guys are right in the fact that the resistance you are measuring is due to the neutral and ground being connected back in a breaker box. If there is a deteriorated wire in a conduit it most likely will not show up with a ohm meter reading. A wet, rotted rubber coating may only be leaking a small amount of current that the meter will not show. You indicate that the wire leading into the lights may be in a conduit. I would try to find a way to bypass that section and see what happens. Perhaps run a section of cable from the last known good point to the first light and power it that way to see what happens
 
Danpik the line I am testing is open at the junction box at the pool pad and goes into the ground ant then into the wall to the first light... Then each light is connected together in the wall (5 of them). I have disconnected the first light from the wall and it's wires now that wire from the junction box to the first light is not connected to anything and it reads no resistance. Guessing I should disconnect all fixtures and test each one the same way? Also wanted to be sure how to test the fixtures as well.
 
Focus on the single fixture you removed. Test the resistance between where the white wire used to connect and where the ground wire used to connect.

Any fixture that is still connected is good based on your earlier tests.

When you get a 0.FL reading the resistance is too high for the meter to measure. That is not "no resistance".
 
Ic thanks Jason. I want to point out that my meter reads ofl when it's not connected, also it reads ofl when it's connected without a bulb in the fixtures. I put a bulb in to have the black wire give me that reading. The white one remains in the k ohms which I thought you said was a problem too?

Pics will follow once I get back to the yard.
 

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Alright, that means that specific wire is good.

So either the fixture, or something else that wire used to be connected to, is bad.

You should be able to pin it down if you continue testing various things, fixtures, other wires, whatever might have been connected to that white wire.
 
OK, so let me tell you what my findings are and what I think.. you guys can correct me if you need to.

you saw all the info above, I apologize, I was doing most of that stuff while I was working... so each time I get a break I would run over and do some testing... sometimes rushed.

So short story... as short as I can make it.

my meter with no contact reads OFL - same as if I am testing a circuit with nothing connected or an open wire. when I tested the run from the wall to the junction box it was disconnected and gave me no continuity or resistance... so other than the shielding it was OK. When I tested the rest of the wire (the line of lights) I got a 7-8 M ohm reading on white, and OFL on the black... it was due to no bulb... I put one bulb in at a time watching the meter and it was the same reading all the way to the last bulb 7-8 M Ohms... so at that point I could see that both lines were same as far as resistance goes, I found the ground wire for the first fixture (it was hanging on by one strand) I replaced it while I was in there. Next... I connected the ground/Black/White back (the wire that runs to the junction box - from the wall) and went back to test... it now reads a consistent 7-8 (did spike up to 9 a few times) but 7-8 was average. this reading was both wires... should I assume that broken ground in the first fixture was the problem? I am not going to put it back together for a week. we have rain coming tomorrow and that will be a great chance to check the wire agn (encase water is part of the problem). after a few days if the two wires show a consistent 7-8 M ohms and my pool light hasn't tripped the breaker (still hasn't caused any trouble) I will add the wall lights back to the circuit and hope for the best...

please let me know your thoughts...

if this works out, I am pulling the fixtures and replacing the ground on them all...
 
I'm not sure. Something was causing the resistance to be in the 30 to 100 k ohm range on the white wire at some point. I don't feel like we have accounted for what that was.

The bad ground is an issue that should be fixed regardless, but it wouldn't cause the resistance to be lower. If anything it would raise the resistance. k ohm is less resistance than m ohm, while 0.FL is more resistance than either.

I'm guessing that the lower resistance was somehow related to water, and that the water has been evaporating. But who knows.

Readings in the m ohm range are promising, and might indicate that you have fixed it. Or they might just indicate that an intermittent problem has gone into hiding for now.
 
Thanks Jason I will keep as is for now, testing it for the next few days... The rain that we have coming will be helpful for testing too. I am not working this weekend so will see what happens. I would feel better if I knew what changed the resistance reading... Only other thing I can think of is that the wire ends need to bd cleaned, could be that working them over with the players helped them get better contact.

Then again the lights sometimes would work with the switch for a while... So time will tell me if it's fixed
 
while a good ground system is important, it has absolutely nothing to do with a GFCI tripping. The ground wire never comes into play in the normal function of a GFCI. A GFCI will work just fine without a ground hooked up and in fact GFCI's are allowed to be used for personal protection in the event there is no ground present. The only way a ground wire ever comes into play in a GFCI circuit is if it is the ground reference source for a current leak. At this point in your testing I think you have arrived at the point where you need to get a good piece of wire and start bypassing sections of the hidden wiring to determine where the problem lies. As I said earlier, you can have a degraded section of insulation that is leaking current. This will not show up as resistance in the wire and unless you use a megger to test it you won't be able to find it.
 
Wonder if I can buy one on eBay (Megger) cheap enough to warrant it anyway... I would like to have one for things like this just to be sure. But yes I agree with you... if I get bad readings or if the breaker trips when I hook it back up I will rewire the wall...
 
They are out there. Remember, with these tools you are dealing with voltages in the thousands range. That hurts real bad. It also can do a lot of damage if not used properly. If you get one make sure it is a good quality one (there are a lot of Chinese cheap-os out there) A good friend got knocked off of a ladder once while using a "cheap" one. Turns out the insulation on the wire leads on the unit was not rated for the voltage the unit could put out. Also make sure there is a good instruction manual with it so you know what it is telling you
 
thnx guys... I will keep an eye out. Till then I will stay on the current path. Most of the work I do is all new circuit small jobs... So I would need to hook into a pretty good deal... too bad I cant just rent one. I guess if I had everything out and ready it wouldn't be too bad to just pay someone to come out and test for me as well.

lets see what happens.. its pouring right now... later on I will check the pool light first of all... if it trips after rain... I quit. If its good, I will keep on messing with the wall. But I don't do electrical work in the rain ;) so will need to wait it out.... even though I know I killed it at the box, and I am sure its volt less at the pad... I just don't like it.

thanks for hanging in there with me... It helps to have other opinions on things I do do that often.
 
OK, I am satisfied... after all the rain, I checked the wall lights again. At the junction box, its back to like 59.9 K ohms... the other end (only checked the two) read 1.358 M Ohms. I didnt disconnect the wires or remove the bulbs, just checked as is... Best I can tell when its wet one side reads in K Ohms, and the other reads in M Ohms. You all think that mans the wire is bad? from my testing with you it looks like it.
 

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