Panel Feeder Question

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Shujinko

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What NEC code section does the feeder installation to this panel violate? The panel is fed from a 100A, 2-pole branch circuit breaker in a distribution panel (120/240V, 1ph, 3w). The feeder size to this panel is (4) #2TW....(2 hots, 1 neutral, 1 equipment ground). I see several violations but I'm looking specifically at the one where the hots land on the main lugs. What section could I refer to that tells me this is a violation? Thanks.
 

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GoldDigger

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Really quick:
Is the lug on the left rated for two conductors?
It looks like a three phase panel which is being fed from single phase 120/240 3-wire.
Instead of leaving one phase bus empty, the third phase bus is being fed in parallel to one of the other two.
This will be confusing when building MWBCs and trying to balance the load on the two ungrounded feeder conductors.
It would be all too easy to double up the allowed load on the left feeder.

Tapatalk!
 

Shujinko

Senior Member
Yes, that is one violation but not the one I'm looking for. Look at the hots and the main lugs, that's the code violation I'm specifically looking for.
 

Shujinko

Senior Member
@Golddigger, not sure if the lug on the left is rated for 2 wires...probably not. I'm wondering if the connecting of the phase A and Phase C lugs is a specific code violation? ANd yes it is a 3-phase panel fed from a 1-phase distribution panel.
 

GoldDigger

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AFAIK there is no inherent violation feeding a three phase panel from a single phase source as long as the concerns I mentioned and others are addressed.
The fact that the branch wires are colored black, red and blue gives me concern that whoever designed and ran the branch circuits may not have had single phase in mind at the time.


Tapatalk!
 

pitkas

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Location
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I dont have my book in front of me but I think its maybe 110.14? One conductor per lug unless listed otherwise. Wonder why they paralleled the grounded conductor? Thats a violation.

Looks like they have green tape on one white. I do not believe you can use white as the grounding conductor, and as said before the lugs are not rated for 2 conductors.

Is that a GE panel? Do I see two different types of breakers?
 
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augie47

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If you are only concerned with the phase terminations, the violation Golddigger referenced would be the only one I would note. I agree with his Post #3 and #7.
 
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GoldDigger

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Looks like they have green tape on one white. I do not believe you can use white as the grounding conductor, and as said before the lugs are not rated for 2 conductors.

Is that a GE panel? Do I see two different types of breakers?
Since the white and white green are both terminated at the same place, it is possible that the run of wire is configured with two hot conductors and two neutral conductors to avoid making the feeder an MWBC. and the green rings just let you identify which is which.
Maybe the wires are part of an AC or MC cable (which may not be properly terminated to the panel) which is using the sheath plus bond wire as the EGC?

OOPS. There is another violation. If the supply wires are really a feeder and not service conductors, the grounded conductors and the EGCs must be electrically isolated. The panel is configured as a service panel. A separate isolated neutral bar must be installed.
 
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norcal

Senior Member
Looks like they have green tape on one white. I do not believe you can use white as the grounding conductor, and as said before the lugs are not rated for 2 conductors.

Is that a GE panel? Do I see two different types of breakers?


The breakers are different generations of GE THQB breakers, & the panelboard seems to be GE also.
 

Shujinko

Senior Member
A wider shot. Also look at the Distribution Panel....3 hots, 1 neutral feeder. Looks like one of the hots isn't landed on a lug, maybe?
 

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augie47

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there are some mwbc that are on the same phase tooo.

This is a mess.

That's an understatement. Most of us can list a half-dozen or more violations but since the OP asked that we specifically address the one issue and it has been answered in posts 3,5,9 & 17. I am closing the thread.
 
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