66 Volts from hot to ground?

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reyamkram

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Hanover park, il
I installed a new ceiling light fixture, (120 volt) and found, from the junction box (ground) to the natural wire I have 10 K ohms, from the hot wire to ground I have 66 volts, and from hot to natural I have 120 volts, , I checked the 120 volt receptacles and from ground to natural I have 3 ohms, and from hot to ground I have 120 volts, and natural to hot I have 120 volts,

To me I believe there is an open ground, so I told the customer I need to come back and start removing covers and find the open ground, and they gave me to OK,
Because I believe there could be a loss or no lock nut in that run

Question, what do you think, am I on the right path???

Thank you all for any and all information.
 
Yes, Mark,the EGC is floating where you are measuring; the high G-N resistance and the load still working tell you that.

You can also garner useful information using a low-impedance tester like a solenoid tester or an incandescent bulb.
 
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I think it is pretty obvious you have an open equipment ground conductor.

Being around the Chicago area it seems likely this thing is run using EMT. If you have both EMT and a green wire it's really strange that you would have an open circuit. You will probably just have to try and trace it back from where it starts and see what the deal is.
 
petersonra said:
I think it is pretty obvious you have an open equipment ground conductor.

Being around the Chicago area it seems likely this thing is run using EMT. If you have both EMT and a green wire it's really strange that you would have an open circuit. You will probably just have to try and trace it back from where it starts and see what the deal is.
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Yes, this is on the North side of Chicago, and there is no EGC just the EMT as the EGC. Thank you, for the information.
 
LarryFine said:
Yes, Mark,the EGC is floating where you are measuring; the high G-N resistance and the load still working tell you that.

You can also garner useful information using a low-impedance tester like a solenoid tester or an incandescent bulb.
Click to expand...
Thank you, for the information, at first I was surprised you know my name, you figured that is good, My wife is from Suffulk VA.
 
LarryFine said:
Yes, Mark,the EGC is floating where you are measuring; the high G-N resistance and the load still working tell you that.

You can also garner useful information using a low-impedance tester like a solenoid tester or an incandescent bulb.
Click to expand...
many year back I had 2 solenoid testers, 1 was Square D and the other was Ideal VOL-CON, thank you again for your replay
 
Light comes on, so whats the problem? (Sarcasm) Most homeowner and others have that feeling, deal with it most every day.

Suggestions so far will help locate, if it is only one point of failure, simple. But if you got one, likelyhood is you got more, and other circuits.

How much is HO or if multi unit owner, willing to invest in finding a safety issue when the "lights come on". We know the safety issues, but I'm interested in how you convince the customer of the labor intensive "repair" necessity.

Now we can get into the classic debate of whether to wire an EGC on EMT or not (code allows EMT as grounding conductor).
 
Fred B said:
Light comes on, so whats the problem? (Sarcasm) Most homeowner and others have that feeling, deal with it most every day.

Suggestions so far will help locate, if it is only one point of failure, simple. But if you got one, likelyhood is you got more, and other circuits.

How much is HO or if multi unit owner, willing to invest in finding a safety issue when the "lights come on". We know the safety issues, but I'm interested in how you convince the customer of the labor intensive "repair" necessity.

Now we can get into the classic debate of whether to wire an EGC on EMT or not (code allows EMT as grounding conductor).
Fred B said:
Light comes on, so whats the problem? (Sarcasm) Most homeowner and others have that feeling, deal with it most every day.

Suggestions so far will help locate, if it is only one point of failure, simple. But if you got one, likelyhood is you got more, and other circuits.

How much is HO or if multi unit owner, willing to invest in finding a safety issue when the "lights come on". We know the safety issues, but I'm interested in how you convince the customer of the labor intensive "repair" necessity.

Now we can get into the classic debate of whether to wire an EGC on EMT or not (code allows EMT as grounding conductor).
Click to expand...
It is just me, and the owner of the building, dose not want the liability, if something happened, now that I informed them, they need to repair it.
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Thank you, for your replay.
 
Fred B said:
Light comes on, so whats the problem? (Sarcasm) Most homeowner and others have that feeling, deal with it most every day.

Suggestions so far will help locate, if it is only one point of failure, simple. But if you got one, likelyhood is you got more, and other circuits.

How much is HO or if multi unit owner, willing to invest in finding a safety issue when the "lights come on". We know the safety issues, but I'm interested in how you convince the customer of the labor intensive "repair" necessity.

Now we can get into the classic debate of whether to wire an EGC on EMT or not (code allows EMT as grounding conductor).
Click to expand...
What bothers me more is how an area that is conduit only would have any open EG. Someone tried to make it fail?

3 ohms seems excessively high for intact EMT.
 
Is this a problem throughout the system or just in a particular area?

Throughout the system might mean main bonding jumper is missing back at the panel? Might not be a bad idea to check there first?
 
ptonsparky said:
What bothers me more is how an area that is conduit only would have any open EG. Someone tried to make it fail?

3 ohms seems excessively high for intact EMT.
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The three ohms covers the full length of the path from where it was measured, to the N-G bond at the service point and back.

It might also include a bit of corrosion where the Ohmmeter leads were connected.
 
kwired said:
Is this a problem throughout the system or just in a particular area?

Throughout the system might mean main bonding jumper is missing back at the panel? Might not be a bad idea to check there first?
Click to expand...
I only checked the one junction box for the light, when I go back I will now more, and I will check to see if the green screw is there,
I do thank you, for your replay.
 
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