Panel disconnect

[Christopher Currins]

200 amp service disconnect outside at meter. Distribution panel inside fed with 3 wire at 200 amp breaker using PVC conduit. Neutrals and grounds terminated together at each bus.

Question- Isn't the panel inside a remote distribution (sub) panel, meaning the neutrals should be isolated?

Also shouldn't this be a 4 wire feed, or can neutral act as ground?

Cutler-Hammer. Pic is best I have.

[Jeffrey R. Pope]

You are correct. The disconnect is located in the service equipment. The other panel is a distribution (sub) panel and should be wired as such - four-wire feed, with isolated neutrals.

[Mark Thorman]

Is that main panel loose or is it an optical conclusion.

www.MauiHomeInspections.com

[Christopher Currins]

Originally Posted by jpope

You are correct. The disconnect is located in the service equipment. The other panel is a distribution (sub) panel and should be wired as such - four-wire feed, with isolated neutrals.

Thanks, thought I was. Been this way since home was built in 'O6, owner is a fire chief and his friend is the small town code inspector.

[Christopher Currins]

Originally Posted by Mark Thorman

Is that main panel loose or is it an optical conclusion.

www.MauiHomeInspections.com

Optical

[Robert Meier]

As stated it should be a 4 wire feeder with the neutrals and EGC's separated at the sub-panel. There also are some issues with the NM cables not being properly secured within 12" of the panelboard.

[Christopher Currins]

Originally Posted by Robert Meier

As stated it should be a 4 wire feeder with the neutrals and EGC's separated at the sub-panel. There also are some issues with the NM cables not being properly secured within 12" of the panelboard.

Thanks, I noted unsecured cables, used for finished basement. Do you know if these Cutler-Hammer breakers can be used for 2 circuits (double tapped) bottom on each side?

[Robert Meier]

Originally Posted by ccurrins

Thanks, I noted unsecured cables, used for finished basement. Do you know if these Cutler-Hammer breakers can be used for 2 circuits (double tapped) bottom on each side?

I can't say with 100% certainty, but I'm 99% sure that they're lugs are not listed for more than one conductor.

A simple splice can fix the problem.

[Christopher Currins]

Originally Posted by Robert Meier

I can't say with 100% certainty, but I'm 99% sure that they're lugs are not listed for more than one conductor.

A simple splice can fix the problem.

99% is good enough for me. That's was my take on it. They kind of appeared to have a slot for 2 conductors, but the only breakers I'm familiar with that allow that are made by Square D.

[Robert Meier]

Originally Posted by ccurrins

99% is good enough for me. That's was my take on it. They kind of appeared to have a slot for 2 conductors, but the only breakers I'm familiar with that allow that are made by Square D.

If you're so inclined you could look in the UL "white book" for the listing of that particular CB.

http://www.ul.com/global/eng/pages/o...l/newsletters/

[Christopher Currins]

Originally Posted by Robert Meier

If you're so inclined you could look in the UL "white book" for the listing of that particular CB.

http://www.ul.com/global/eng/pages/o...l/newsletters/

Thanks Robert. I did find that the breaker in question,CH BR, is not designed for 2 conductors.

[Greg Keene, CPI]

Just a thougt, but the panel inside may not be a sub panel. I have seen main disconnects at the meter where the ground and nuetral were not bonded at the shut off, but they were bonded inside the main distribution panel. If that is the case, then the inside panel is not a sub and the ground and neutral would be bonded inside. Sometime you have to remove the dead front at the disconnect to see what is happeneing.

[Christopher Currins]

Originally Posted by gkeene

Just a thougt, but the panel inside may not be a sub panel. I have seen main disconnects at the meter where the ground and nuetral were not bonded at the shut off, but they were bonded inside the main distribution panel. If that is the case, then the inside panel is not a sub and the ground and neutral would be bonded inside. Sometime you have to remove the dead front at the disconnect to see what is happeneing.

So if the neutral is not bonded to ground at service "main" disconnect and there is only a 3 wire feed, 2 hots and 1 neutral, as with this panel, with neutral connected to ground bus, where is the path to earth?

Also when the service wire from the meter connects to the disconnects, the disconnects are now considered the "main service". All grounding must be bonded together with the neutrals at this point. Any service panels after this point, whether it's the main service or not, is now considered a "sub-panel" and both the ground wires and neutral wires must be isolated from each other.

[Jeffrey R. Pope]

Originally Posted by gkeene

Just a thougt, but the panel inside may not be a sub panel. I have seen main disconnects at the meter where the ground and nuetral were not bonded at the shut off, but they were bonded inside the main distribution panel. If that is the case, then the inside panel is not a sub and the ground and neutral would be bonded inside. Sometime you have to remove the dead front at the disconnect to see what is happeneing.

I think you will find this to be incorrect.

There is "service" equipment, and there is "other" equipment. The service-disconnect is located in the service equipment. At that point, there must be a connection to earth, which must be bonded to the service neutral. Refer to NEC 250.24(A) & 250.24(A)(1)

Any panels/equipment on the load-side of the service equipment must have neutrals isolated from the grounding conductors (some exceptions do apply) - Refer to NEC 250.24(A)(5)