Grounded conductor from different panelboard

[augie47]

I have an installation with two service panels and a generator panel.
The transfer switch is fed from Panel A (and of course, the generator) which then feeds the generator panel.
The neutral from Panel A and the Generator continue (unswitched) to the generator panel.
From the generator panel several branch circuits are routed back to panel A.
No neutrals are run from the generator panel.
The neutrals for these circuits remain terminated in panel A.
This seems to be a violation of 300.3(B).
In addition, several circuits from the generator panel (phase conductors only) run to the other service panel "B" and feed circuits there.
What Code sections does this violate ??
(none are MWBC to 210.4 is not involved)

 

[petersonra]

Do you really have two service panels?

 

[augie47]

Yes. Actually (3) but only (2) are involved with the generator , 3 risers, CT metered. Large house

 

[lakee911]

Large house

Wow. LOL

 

[Little Bill]

I have an installation with two service panels and a generator panel.
The transfer switch is fed from Panel A (and of course, the generator) which then feeds the generator panel.
The neutral from Panel A and the Generator continue (unswitched) to the generator panel.
From the generator panel several branch circuits are routed back to panel A.
No neutrals are run from the generator panel.
The neutrals for these circuits remain terminated in panel A.
This seems to be a violation of 300.3(B).
In addition, several circuits from the generator panel (phase conductors only) run to the other service panel "B" and feed circuits there.
What Code sections does this violate ??
(none are MWBC to 210.4 is not involved)

I'm confused as to why if you have a generator panel you have circuits routed back to a main panel?

I'm used to seeing a generator panel that has the circuits to be backed up. The generator panel is fed from the transfer switch from either utility or generator power. I'm not seeing why you would route circuits back to another panel!:?

What am I missing here?

 

[Smart $]

... I'm not seeing why you would route circuits back to another panel!:?

What am I missing here?

My guess would be the generator, transfer switch, and gen' panel were add-ons to an existing installation, where the circuits where originally run to the service panels.

As for the circuits run back to panel A, we need more details. Raceway wiring method? Circuits contained in same raceway as gen' panel feeder? That wouldn't be a violation because all circuit conductors would be essentially be switch legs. Now if the circuit conductor are in a separate raceway or cable(s), that'd be a violation of 300.3(B).

As to the circuits going to panel B, if no neutrals accompanying them and they go directly to panel B, seems obvious they are in violation of 300.3(B).

 

[augie47]

I'm confused as to why if you have a generator panel you have circuits routed back to a main panel?

I'm used to seeing a generator panel that has the circuits to be backed up. The generator panel is fed from the transfer switch from either utility or generator power. I'm not seeing why you would route circuits back to another panel!:?

What am I missing here?

As Smart$ noted, the generator was added years after the original install. The circuits originally landed in the service panel and the selected ones were lifted off those breakers and connected to the generator panel.. The neutrals were not disturbed...which is the problem I see,

My guess would be the generator, transfer switch, and gen' panel were add-ons to an existing installation, where the circuits where originally run to the service panels.

As for the circuits run back to panel A, we need more details. Raceway wiring method? Circuits contained in same raceway as gen' panel feeder? That wouldn't be a violation because all circuit conductors would be essentially be switch legs. Now if the circuit conductor are in a separate raceway or cable(s), that'd be a violation of 300.3(B).

As to the circuits going to panel B, if no neutrals accompanying them and they go directly to panel B, seems obvious they are in violation of 300.3(B).

The feeder to the transfer switch is a piece of SER from panel "A" (12) circuits (phase conductors only) from the generator panel are routed back to a j box then distributed to A and B

 

[Smart $]

...

The feeder to the transfer switch is a piece of SER from panel "A" (12) circuits (phase conductors only) from the generator panel are routed back to a j box then distributed to A and B

Code edition under which it was installed?

The SER is a good indicator of non-compliance, but not an absolute one. Still have to rule out non-ferrous wiring methods under 300.3(B)(3) for the "switch legs".

 

[Dennis Alwon]

Why would ser be non-compliant

 

[Smart $]

Why would ser be non-compliant

Not the SER itself... it means the ungrounded circuits going back to panel A are not in the same cable regarding compliance with 300.3(B) general requirement... but being SER is a nonferrous wiring method, have to rule 300.3(B)(3) out, too.

 

[augie47]

'08 Code install. SER is the feeder to the transfer switch from Panel A.
The branch circuits from the generator panel are routed in PVC conduit.
(I don't see where that makes a difference, Code-wise)

 

[Smart $]

'08 Code install. SER is the feeder to the transfer switch from Panel A.
The branch circuits from the generator panel are routed in PVC conduit.
(I don't see where that makes a difference, Code-wise)

Because 300.3(B)(3) non-ferrous wiring methods can qualify as meeting the general requirement of 300.3(B)...

(3) Nonferrous Wiring Methods. Conductors in wiring​

methods with a nonmetallic or other nonmagnetic sheath,​

where run in different raceways, auxiliary gutters, cable trays,​

trenches, cables, or cords, shall comply with the provisions of​

300.20(B).​

The thing about 300.3(B)(3) is not having any proximity requirement... but it is what it is.

 

[Smart $]

What may make the circuits routed to panel A non-compliant is 210.4 regarding multiwire branch circuits... must originate in the same panelboard. I don't know of any such requirement for non-multiwire branch circuits.

 

[Smart $]

Another possible issue is conductors of the same circuit not entering and/or exiting through the same knockout in a ferrous enclosure. May require slots between knockouts, or equivalent remedy. Forget the section offhand.

 

[iwire]

Another possible issue is conductors of the same circuit not entering and/or exiting through the same knockout in a ferrous enclosure. May require slots between knockouts, or equivalent remedy. Forget the section offhand.

300.20(B) its referenced in 300.3(B)(3)

 

[Little Bill]

My guess would be the generator, transfer switch, and gen' panel were add-ons to an existing installation, where the circuits where originally run to the service panels.

As Smart$ noted, the generator was added years after the original install. The circuits originally landed in the service panel and the selected ones were lifted off those breakers and connected to the generator panel.. The neutrals were not disturbed...which is the problem I see,

I understand about the generator being added after the initial install. I was confused over this:

From the generator panel several branch circuits are routed back to panel A.

I don't look at it as the conductors being "routed back". I just look at it as the original branch circuit being lifted off the breaker, wire-nutted to another conductor that runs TO the generator panel.

But I guess you could look at it as being "routed back" but it is the same conductor that leaves the main panel. It just gets fed from a different place.
It just didn't click with me that we were talking about the same method just worded different!

Side note:
I run the grounded conductors, but not the EGCs, to the generator panel. Usually don't have to keep the grounded conductors in any order unless they go to a GFCI/AFCI.
I might know someone who forgot to keep the grounded conductors with the ungrounded (identified) then had to sort them out because the breaker wouldn't set!:happysad: