Three phase panel used for single phase service. Violation?

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kwired said:
So is labor, knowing what to use and how to use it is expensive:happyyes:
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I'd have to tend to agree with that in another aspect also.

I can opt to do a panel change out for free if I want to.

The supply house is not going to let me leave the building without charging me for the material.

JAP>
 
Back Feed Circuit Breakers.

Back Feed Circuit Breakers.

Note that not many circuit breakers are U.L. listed for use as power being fed to the breaker's LOAD terminals.

This may likely also void the manufacturer's warrantee unless the breakers are rated by the MFR. as being suitable for being back fed.
 
Skokian said:
Note that not many circuit breakers are U.L. listed for use as power being fed to the breaker's LOAD terminals.

This may likely also void the manufacturer's warrantee unless the breakers are rated by the MFR. as being suitable for being back fed.
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Not sure they have to be listed that way, not a standard thermal-magnetic breaker anyway. GFCI, AFCI, and other electronic controlled units will likely have a definite line and load side that you must connect properly or they won't necessarily work properly.

Approved hold down devices likely wouldn't even be made if there were no breakers listed to use with them. Often there are limitations in the loadcenter as to where such hold down device can be installed as well. There are also certain loadcenters with a factory installed back fed main breaker.
 
Skokian said:
Note that not many circuit breakers are U.L. listed for use as power being fed to the breaker's LOAD terminals.

This may likely also void the manufacturer's warrantee unless the breakers are rated by the MFR. as being suitable for being back fed.
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Not sure where you're getting your information. I think the opposite is true, except for breakers with additional functions (GFCI, ACFI, GFP). Ever since I've known the code, 690 and 705 have had informational notes that say that breakers not marked 'line' and 'load' are suitable for backfeed. I've never seen a simple thermal magnetic breaker that was marked that way from the factory.

And as for the panelboards that have explicit instructions for installing a backfed breaker, well, clearly those breakers are listed for that.
 
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If I were an inspector, I wouldn't pass it. I would cite the Code reference that says products need to be used for their intended purposes. The panel in question was intended to be used on a 3-phase service. In this case, it clearly is not being used in that manner.
 
jeff48356 said:
If I were an inspector, I wouldn't pass it. I would cite the Code reference that says products need to be used for their intended purposes. The panel in question was intended to be used on a 3-phase service. In this case, it clearly is not being used in that manner.
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Are single-phase panels "intended to be used" as 120V panels with both buses in parallel?
 
jap said:
Actually that section requires it to be marked for the number of "Phases" not the number of "Buses".

There is not 3 phase inside the panel as the cover would suggest, therefore I would consider it a violation of this rule.

JAP>
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just because it is rated and marked for 3 phase does not mean you have to use all 3 phases. otherwise you would not be allowed to install a 2 pole breaker in a 3 phase panel.
 
jeff48356 said:
If I were an inspector, I wouldn't pass it. I would cite the Code reference that says products need to be used for their intended purposes. The panel in question was intended to be used on a 3-phase service. In this case, it clearly is not being used in that manner.
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the code does not say that.
 
MAC702 said:
If you were an inspector, would you also not approve them being used in such a way?
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I'm trying to figure out what you mean by the panel being used as a 120v panel with both busses in parallel?

JAP>
 
jap said:
I'm trying to figure out what you mean by the panel being used as a 120v panel with both busses in parallel?
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We started discussing it on post 30, but you then made the good point that the number of phases on the label is more notable than how the buses are used. I forgot about that.
 
GoldDigger said:
:thumbsup:
The closest it comes is that the use must be consistent with (not conflict with) any manufacturer's instructions which are part of the listing process.
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I don't see how a 3 phase interior, and, a cover that states that what's inside the panel is 3 phase, when opened up, is actually not 3 phase,but a jury rigged single phase setup, would not be consistent, or a conflict with what the manufacturer's label indicates on the outside of the panel.

JAP>
 
To me, a panel labeled 3 phase on the outside, but, being wired as single phase distribution on the inside, is both a conflict, and, not consistent with what the panel cover says it is.

JAP>
 
jap said:
To me, a panel labeled 3 phase on the outside, but, being wired as single phase distribution on the inside, is both a conflict, and, not consistent with what the panel cover says it is.

JAP>
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Sure, it's inconsistent. I don't believe "inconsistent" means Code violation.
 
jap said:
Is the wording in Post #52 actually in the code book or not?

I didn't look.

JAP>
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Not exactly. But the relevant words in Post #52 are "Manufacturer's Instructions." A label which says that the panel is three phase is not an "instruction."
 
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