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Sam Morris
05-21-2015, 05:58 PM
The main disconnect was outside and the AKA sub-panel was inside. Actually panels were back to back. My question is, aren't the neutrals and grounds suppose to be separated (shouldn't the bonding jumper bar be disconnected ?? Was a 200 amp service with 2 hots a neutral and ground. This panel is currently be wired as a service panel ?

Jerry Peck
05-21-2015, 06:16 PM
The main disconnect was outside and the AKA sub-panel was inside. Actually panels were back to back. My question is, aren't the neutrals and grounds suppose to be separated (shouldn't the bonding jumper bar be disconnected ?? Was a 200 amp service with 2 hots a neutral and ground. This panel is currently be wired as a service panel ?

You are referring to two panels and either inter-mixing your questions or ... I'm simply not following which panel you are referring to for which question. The intentional addition of your term referencing submarine panels did not do anything to clear your questions up.

Why not try it without the intentional reference to submarine panels and clarify your questions, such as:
a) There is a service equipment panel is outside, we'll call this the Service Equipment panel (because this is the Service Equipment panel).
b) There is a panel inside, we'll call this Panel A (this is the not-service-service-equipment-panel but Panel A is less cumbersome to use).

Okay, now, from the information you provided:

- The Service Equipment panel is outside, and has a 200 amp service disconnect in it. No, the bonding jumper should not be disconnected in the Service Equipment panel, the opposite is required - the neutral (grounded conductor) is required to be bonded to ground in the Service Equipment panel.

- The other panel, Panel A, is directly inside the Service Equipment panel on the same wall but inside the house. Yes, the bonding jumper should be disconnected in Panel A, the neutral is required to be isolated from ground in Panel A.

At least that is what I am reading from your information.

Sam Morris
05-21-2015, 06:39 PM
[QUOTE=Jerry Peck;257699]You are referring to two panels and either inter-mixing your questions or ... I'm simply not following which panel you are referring to for which question. The intentional addition of your term referencing submarine panels did not do anything to clear your questions up.

Why not try it without the intentional reference to submarine panels and clarify your questions, such as:
a) There is a service equipment panel is outside, we'll call this the Service Equipment panel (because this is the Service Equipment panel).
b) There is a panel inside, we'll call this Panel A (this is the not-service-service-equipment-panel but Panel A is less cumbersome to use).

Okay, now, from the information you provided:

- The Service Equipment panel is outside, and has a 200 amp service disconnect in it. No, the bonding jumper should not be disconnected in the Service Equipment panel, the opposite is required - the neutral (grounded conductor) is required to be bonded to ground in the Service Equipment panel.

- The other panel, Panel A, is directly inside the Service Equipment panel on the same wall but inside the house. Yes, the bonding jumper should be disconnected in Panel A, the neutral is required to be isolated from ground in Panel A.

At least that is what I am reading from your information.[/QUOTE

Is there a 2 ft rule (panel can be wired as a main if it has metal conduit between the two panels) ??

Jerry Peck
05-21-2015, 07:20 PM
Is there a 2 ft rule (panel can be wired as a main if it has metal conduit between the two panels) ??

No, the code basically says 'the neutral is to be bonded to ground at the service equipment' and 'the neutral shall be isolated from ground beyond the load side of the service disconnect' (and the service disconnect is within the service equipment, so not outside the service equipment beyond the load side of the disconnect).

Panel A in your description is 'outside the service equipment and is downstream of the load side of the service disconnect.

Here is another scenario: service equipment enclosure on the left, Panel A mounted directly to the right side of the service equipment enclosure with a chase nipple (presuming the covers of both will still close and not interfere with each other) - the two are side-by-side and only about a 1/16 inch apart (if that, may even be tight to each other) ... the neutral would still be required to be isolated from ground in Panel A.

Jim Port
05-22-2015, 07:55 AM
A metallic conduit between panels could serve as the 4th conductor.

Jim Hintz
05-27-2015, 08:13 AM
Personally, when there is a disconnect under the power meter, I refer to that panel / box as the "Meter Set" and every panel downstream of the "Meter Set" is a remote / sub-panel. Most of the time you see a disconnect at a meter set around mobile homes and in condos / apartment buildings, not so much on stick-built unless you're out in the Boonies. JMO.

Jerry Peck
05-27-2015, 10:46 AM
Personally, when there is a disconnect under the power meter, I refer to that panel / box as the "Meter Set" ...

That would be the meter and the service equipment, unless in one combination enclosure, then it would be a combination meter and service equipment.

A "meter set" is when the power company goes out and sets the meter.


... and every panel downstream of the "Meter Set" is a remote / sub-panel.

Why throw all the extra terminology in there? It is simply a "panel".

There are basically two types of panels:
- a panel which is being used as service equipment
- a panel which is not being used as service equipment

So why not just call one the "service equipment panel" and just call the other a "panel"?

Not sure why it seems sooooo hard to grasp.


Most of the time you see a disconnect at a meter set around mobile homes and in condos / apartment buildings, not so much on stick-built unless you're out in the Boonies. JMO.

Every structure is required to have a disconnect (actually, up to 6 disconnects for the one service).

Mobile homes will have the service equipment mounted on a pole or a pedestal, when mounted on poles, the meter is frequently a separate enclosure from the service equipment panel, however, when pedestals are used, they contain a both and are combination meters/service equipment panel.

Apartment buildings and condos are "one" building, thus will have "one" service and one (actually allowed up to 6) service disconnects, and they will be grouped together, typically in an electrical room. From that service equipment will be feeders which feed a "main disconnect" (but not a "service disconnect) for each apartment or condo (unless there are only 6 units, then there may be 6 "service disconnects").

Townhouses and one-and two-family dwellings will be like all other structures - one service to each structure (each townhouse is its own structure) and the associated service equipment for that structure.

That is a short version, it actually can get more complicated than that, but that will typically be for large commercial, institutional, industrial settings.

david shapiro
05-30-2015, 08:17 AM
.[/QUOTE

Is there a 2 ft rule (panel can be wired as a main if it has metal conduit between the two panels) ??

[I've been trying to find it; I think it's in the same book as the 5 second rule for rescuing food dropped to the floor.]

I suspect that some jurisdictions allow no more than 2 ft of unprotected service conductors to enter a building before they enter an enclosure containing the main disconnect.

And on to your question:

The neutral and ground are jumpered at one location only. Could be a disconnect that's part of the meter stack. Could be a free-standing disconnect. Could be a disconnect that's in a service panel with branch circuits.
ANYTHING in a panel downstream of this location must keep the neutrals floating, and any grounding conductors bonded to metal enclosures.