Back feed breaker

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A student backfed a breaker to use it as a main breaker in a panel. He used an approved clip to mechanically hold the breaker in place. The electrical inspector told him he could not use the breaker spaces across from the breaker he used for the main for any branch circuits. I checked in the code book but could not find anything to support the inspectors ruling. The panel also did not have any listing on it to support the ruling. The panel was a 200 amp Cutler hammer BR and the breaker was 100 amp. Is the inspector correct?
 

roger

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You are correct that if it is not stated in the listing and labeling information and manufacturers instructions there is nothing in the NEC prohibbiting it. The inspector needs to provide substantiation to his claim.

Roger
 

raider1

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I agree with Roger, unless the panel manufacturer has information in the listing and labeling of the panel prohibiting installing breakers opposite from the back fed breaker the inspector is incorrect.

Chris
 

don_resqcapt19

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Most panles have instructions that limit the total breaker rating on a single set of fingers. In this case that does not seem to be an issue, but as I recall there is a panel that limits you to a total of 100 amps on any bus finger. The following is from Eaton and applies to their BR panels.
The sum of the handle ratings connected to any stab is limited to 150A maximum on the 100 and 125A loadcenters, and 200A on loadcenters with 150A or higher main bus.
 
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Dennis Alwon

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Most panles have instructions that limit the total breaker rating on a single set of fingers. In this case that does not seem to be an issue, but as I recall there is a panel that limits you to a total of 100 amps on any bus finger. The following is from Eaton and applies to their BR panels.
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All the 200 amp resi panel boards I know allow 125 amp on the fingers. Well they accept 125 amp breakers-- I will have to check that. I assume they are talking actual load and not breaker size when they say 100 amps.
 

Joethemechanic

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Hazleton Pa
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Electro-Mechanical Technician. Industrial machinery
That's funny, I just came across a Siemens panel the other day that had a pair of 100 amp breakers on the same set of stabs but they were interlocked. One was the main, and the other was for the standby generator. I thought about it for a minute, but considering they were interlocked I didn't worry too much about it.
 

dhalleron

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Location
Louisville, KY
I've always been told not to use the spaces across from a main breaker, but never really looked into it.

Yesterday I was working on an estimate and looked inside a Siemens sub panel. It was feed with one of those main lug kits that plug in like a breaker. The name escapes me now. Anyway, someone had wrote on the label for the spaces across from it DO NOT USE.
 

Cow

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Eastern Oregon
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Electrician
All the 200 amp resi panel boards I know allow 125 amp on the fingers. Well they accept 125 amp breakers-- I will have to check that. I assume they are talking actual load and not breaker size when they say 100 amps.

I would think the manufacturers don't want more than 125 amps of load from each stab. But if one breaker was FEEDING the panel and not pulling a load, why would it matter if the breakers added up to more than 125 amps, from a practical standpoint?
 

don_resqcapt19

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I would think the manufacturers don't want more than 125 amps of load from each stab. But if one breaker was FEEDING the panel and not pulling a load, why would it matter if the breakers added up to more than 125 amps, from a practical standpoint?
Part of the stab or finger would see the total of the current on both breakers.
 

the blur

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cyberspace
where can one find the clip to secure a "main breaker" in an old GE panel board? It's a sub panel with a back fed main, and I'm tired of seeing this oversight on the hack that installed it. I asked in 3 supply houses, and it's not too common.
 

norcal

Senior Member
where can one find the clip to secure a "main breaker" in an old GE panel board? It's a sub panel with a back fed main, and I'm tired of seeing this oversight on the hack that installed it. I asked in 3 supply houses, and it's not too common.

How old is the panel? If it predates the requirement for a hold down bracket there may not be one avail. for it.
 

summitville

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Ohio
Part of the stab or finger would see the total of the current on both breakers.

Given that the original poster stated that a 100 Amp breaker was used to backfeed the Service Panel. So, let's assume that 100 amps is actually being backfed IN. I then suggest that all bus components and all other breakers must have 100 or less amps flowing OUT. After the 100 amps flows into the stab from the Backfed Breaker it SPLITS into amperage flowing to the opposite breaker and amperage flowing down the main bus bar to the other breakers. If a 60 amp breaker was directly across from the backfeed breaker then 60 amps would immediately flow across the stab and the remaining 40 amps flows down the stab to the bus to the other breakers. At no point was there any current higher then 100 amps.

Please explain how there can be more than 100 amps flowing through any part of the stab.
 
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