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Sam Morris
05-22-2019, 05:34 PM
Is this panel still a AKA sub-panel ?? (panel on right) Because the Bus bars are bonded together with jumper and bonding screw is still on the neutral side, but the neutrals are on the neutrals side and grounds are on ground side (separated). There is 200 main disconnect beside this panel (see pictures) Thanks In Advance

Gunnar Alquist
05-22-2019, 05:44 PM
Is this panel still a AKA sub-panel ?? (panel on right) Because the Bus bars are bonded together with jumper and bonding screw is still on the neutral side, but the neutrals are on the neutrals side and grounds are on ground side (separated). There is 200 main disconnect beside this panel (see pictures) Thanks In Advance

Sam,

Man, those are some teeny pics. I can't see much going on there. Also, it would be helpful if you got your terminology correct so I could understand you a bit better.

As JP regularly says, the service equipment is the only place where neutral and equipment ground should be bonded (well... ok, not entirely true. Bonded at the transformer as well, but we don't inspect transformers, so...).

As a result, I will take a stab (hopefully) in the right direction. If neutral is bonded to the equipment ground in any fashion or at any other location other than the service equipment, then it is incorrect.

Except... :cool:

Sam Morris
05-22-2019, 06:07 PM
Sam,

Man, those are some teeny pics. I can't see much going on there. Also, it would be helpful if you got your terminology correct so I could understand you a bit better.

As JP regularly says, the service equipment is the only place where neutral and equipment ground should be bonded (well... ok, not entirely true. Bonded at the transformer as well, but we don't inspect transformers, so...).

As a result, I will take a stab (hopefully) in the right direction. If neutral is bonded to the equipment ground in any fashion or at any other location other than the service equipment, then it is incorrect.

Except... :cool:

Thanks for your help, I've got all that down, Im sorry about those pictures, my Nikon battery died on me after taking 330 pictures today.

Jerry Peck
05-22-2019, 06:44 PM
An answer in the form of a question:

You said there was a panel with a main service disconnect in it, correct?

If so, THAT panel (with the first service disconnect in it), whether inside or outside, is "the" "service equipment panel".

All other panels "are not service equipment panels" (keeping in mind that one could have up to six "service equipment panels grouped together in one location where each panel had a main service disconnect in it).

Being as you describe "one" panel with "the" service disconnect in it, then the exception I mentioned for the 'up to six' doesn't apply, meaning that you only have one service equipment panel with one main service disconnect.

The others should not have the neutral conductor bonded to ground, and a separate grounding conductor is required (which could be metallic conduit with the proper connections).

Sam Morris
05-22-2019, 07:10 PM
An answer in the form of a question:

You said there was a panel with a main service disconnect in it, correct?

If so, THAT panel (with the first service disconnect in it), whether inside or outside, is "the" "service equipment panel".

All other panels "are not service equipment panels" (keeping in mind that one could have up to six "service equipment panels grouped together in one location where each panel had a main service disconnect in it).

Being as you describe "one" panel with "the" service disconnect in it, then the exception I mentioned for the 'up to six' doesn't apply, meaning that you only have one service equipment panel with one main service disconnect.

The others should not have the neutral conductor bonded to ground, and a separate grounding conductor is required (which could be metallic conduit with the proper connections).

I've got it, ALL other panels down stream from the service disconnect are secondary distribution panels

Ben Jacks
05-23-2019, 02:01 AM
I've got it, ALL other panels down stream from the service disconnect are secondary distribution panels

The Main Service Disconnect panel on the left is considered the main service panel for feeders, whereas the panel on the right is being used for BC distribution. I know from many years back how some scholarly contributors frowned on the terminology 'sub-panel' so I have avoided it's usage here mainly due to the fact that the inner grounded conductor terminal bar and the grounding conductor terminal bar are transposed and bonded together. The 4 wire cabling from the disconnect box on the left must have the Neutral Circuit grounded cable to be terminated on the left side terminal bar and the EGC bare grounding cable terminated on the right bar.
The split phase ungrounded conductors Leg A and Leg B are terminated to Bus Bars as the correct secret hand shake electrician's terminology. All four cables are isolated from each other in this four-wire panelboard. The green main bonding screw is bonded only in the MAIN service panel and the main jumper bus in the right panel only bonded to the grounding strip from the metal chassis enclosure. I hope this helps. Note that there must be a conductive bond between both electrical enclosures. rbj

david shapiro
05-23-2019, 03:49 AM
Sometimes we'll find a panel with the neutral bonded to the cabinet where this used to be the service panel and was converted to a subpanel. These can be a mess, with the need to separate grounds and neutrals that have lived together in cozy consanguinity--which has been downgraded to miscegenation. They still need to be separated, and the system bonding jumper removed to float the neutral.