[bagnammit]

I am having a very troubling issue on my current job. I have a single phase 400A service entering a greenhouse from central metering at a pole out in the field. Off that service there are 4 x 200A and 1 x 100A sub panels. When any of those main breakers are isolated I can read 110V from any live phase to that particular breaker (which is open at both ends). Anyone ever heard or seen this before? It seems to be effecting the system downstream for the new led lights i have installed.

 

[CFL]

Can you try to explain that better. You need to tell us exactly what points you are testing from.

 

[Ol timer]

Odd voltage

By isolated, your saying "open" and testing on the load side of the "open" main, is that correct?

 

[bagnammit]

yes. that is correct, i am testing from the load side of the absolute main 400A breaker to any sub main in the same load centre. With any distribution breaker in the load centre open and their main on the panel down the line open, as well as the neutral disconnected at both points you will read around 108V between that load side of the 400A main (which is on) and any of those wires. Its like reading neutral or ground potential off a wire in thin air.

 

[CFL]

yes. that is correct, i am testing from the load side of the absolute main 400A breaker to any sub main in the same load centre. With any distribution breaker in the load centre open and their main on the panel down the line open, as well as the neutral disconnected at both points you will read around 108V between that load side of the 400A main (which is on) and any of those wires. Its like reading neutral or ground potential off a wire in thin air.

I'm still a little confused on how you are doing this, but in any case, what type of meter are you using? Are you sure it's not ghost voltage?

 

[bagnammit]

fluke, its good

 

[Wyremonkey]

You're getting a reading of 110 between the line side of your main and the load side of an, open on both sides, sub service?
Have you tried using a light bulb instead of your multimeter. Sounds fishy

 

[bagnammit]

yes wryemonkey, sub 200A breaker open on both ends, either line to line side of 400A main reads 110V. its also reads 110 to the neutral when i have pulled it off the neutral bus at both ends.

 

[Ontariojer]

When you shut off the main in the sub panel, you are picking up the 'neutral' through a connected load on any of the circuits on that panel. Turn off ALL the breakers in the panel. The voltage will vanish. Also, use a wiggy, for real.

 

[CFL]

fluke, its good

Brand doesn't matter, but sounds like you have a high impedance tester, follow?
I'm not saying that's your problem, just getting that out of the way. Just ask if you don't understand why I ask.

 

[CFL]

When you shut off the main in the sub panel, you are picking up the 'neutral' through a connected load on any of the circuits on that panel. Turn off ALL the breakers in the panel. The voltage will vanish. Also, use a wiggy, for real.

You shouldn't recommend a wiggy. He's testing at the service. A low impedance meter is what he needs, but other than a wiggy.

 

[bagnammit]

never heard of a wiggy, but i do have all breakers off and wires pulled out

 

[bagnammit]

had hydro one there today using there meter, same result

 

[hardworkingstiff]

I have no idea of what the OP is trying to communicate.

 

[CFL]

When you shut off the main in the sub panel, you are picking up the 'neutral' through a connected load on any of the circuits on that panel. Turn off ALL the breakers in the panel. The voltage will vanish. Also, use a wiggy, for real.

The way he describes it, none of the feeders are terminated, and the upstream breaker is open. The voltage would have to be coming from somewhere else.

 

[CFL]

had hydro one there today using there meter, same result

Is hydro one the POCO?

 

[Ontariojer]

The way he describes it, none of the feeders are terminated, and the upstream breaker is open. The voltage would have to be coming from somewhere else.

Ah, that's not how I was reading it. Thx.

 

[bagnammit]

they are on central metering, i have checked for something coming in from another one of services at the pole, but to no avail

 

[bagnammit]

hydro one is the local power utility provider, i called them to check there lines at the high voltage transformer.

 

[CFL]

they are on central metering, i have checked for something coming in from another one of services at the pole, but to no avail

I don't know what central metering means. Who is hydro one? Do you understand the problem with your meter?