Circuit breaker height in a panel

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dannyrzk

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During a site visit to a project, I noticed an MLO panel (PB) to have some circuit breakers above 6'-7", some up to +91". This panel is connected to the MDP in the same room, which has the panel PB disconnect at a proper height.
My question: Is IMG_E0626.JPGpanel PB violating the code? (section 404.8)
 
Side question: why place multi-pole breakers head-to-head? (Yes, I admit I don't know the amperages)
 
dannyrzk said:
During a site visit to a project, I noticed an MLO panel (PB) to have some circuit breakers above 6'-7", some up to +91". This panel is connected to the MDP in the same room, which has the panel PB disconnect at a proper height.
My question: Is View attachment 2552553panel PB violating the code? (section 404.8)
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Absolutely yes


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LarryFine said:
Side question: why place multi-pole breakers head-to-head? (Yes, I admit I don't know the amperages)
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In my installations, it’s because that’s how the engineer drew it, so that’s how Square D built it.

I’ve always thought head-to-head wasn’t an issue in a bolt on bus. Adjacent breakers can still be an issue.

Typically in my restaurant work, the engineers will draw out fryer and grill panels to have an empty space between all of the 50/3 breakers.


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Jon456 said:
Since the OP's question has been answered, may I go off-topic and ask what would the issues be with head-to-head multi-pole breakers?
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There is absolutely no problem if they're within the size range permitted by the manufacturer of the panel. Since they're connected to the same bus stabs the current on those stabs would be additive for both breakers. The stab may be only rated to carry 100 amps so installing 2-100 amp circuit breaker opposite each other could overload that stab. If that same stab had two opposite 50 amp breakers there would be no issues.
 
infinity said:
There is absolutely no problem if they're within the size range permitted by the manufacturer of the panel. Since they're connected to the same bus stabs the current on those stabs would be additive for both breakers. The stab may be only rated to carry 100 amps so installing 2-100 amp circuit breaker opposite each other could overload that stab. If that same stab had two opposite 50 amp breakers there would be no issues.
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Thank you. That makes sense. So the issue is not that they're multi-pole breakers per se, but that multi-pole breakers tend to have higher current ratings than single-pole breakers?
 
Jon456 said:
Thank you. That makes sense. So the issue is not that they're multi-pole breakers per se, but that multi-pole breakers tend to have higher current ratings than single-pole breakers?
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Exactly. (y)

We did a job where we had a large 3Ø panel with several 100 amp, 3-pole CB's. From the factory they came installed all on the left side of the panel. The guy who tied the panel in decided it would be neater if he moved 1/2 of them to the right side opposite the CB's on the left. The bus stabs were only rated for 125 amps creating a potential hazard.
 
infinity said:
Exactly. (y)

We did a job where we had a large 3Ø panel with several 100 amp, 3-pole CB's. From the factory they came installed all on the left side of the panel. The guy who tied the panel in decided it would be neater if he moved 1/2 of them to the right side opposite the CB's on the left. The bus stabs were only rated for 125 amps creating a potential hazard.
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If they actually are loaded to near capacity then you won't be seeing that many in a typical QO panel as it won't take many to exceed the capacity of the panel anyway. Next step up in Square D equipment is I line panel, where the breaker plugs directly to the main bus and not to a link from the main bus. I have installed I line panels with nothing less than a 100 amp breaker installed in the entire panel.
 
Dennis Alwon said:
I have never seen an 84 cir panel...
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I have installed a few.

Throw in a 400 or 600 amp main breaker and the height becomes more significant to pay attention to, especially if bottom mounted main.

Can get 84 circuits easier out of QO that is only 3/4 inch wide than others that are 1 inch wide and not get too tall.
 
Coppersmith said:
A 30x36x12 platform will solve the problem.
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dannyrzk said:
Coppersmith, can you please elaborate a little more? Thanks
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If the panel is located too high, you can raise the floor by providing a permanent sturdy platform to stand on. If it is at least 30x36 it covers the required working space. The highest breaker in the panel was 91" which is 12 inches too high. A 12" tall platform is needed. I would suggest guard rails at that height. The platform could be made of concrete, wood, metal, or any other building material.
 
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I’ve had to install RV step platforms at generators because the main was too high because of the belly tank.They have a handrail, and the inspectors were happy with it.
 
hillbilly1 said:
I’ve had to install RV step platforms at generators because the main was too high because of the belly tank.They have a handrail, and the inspectors were happy with it.
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I've had to install platforms on generators numerous times as well and most times just had the manufacturer include a platform in their pricing.

Roger
 
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