Circuit breaker blanks

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bmoc76

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I just had a safety inspection on one of my panels and was told that I didn't have the correct blanks in the panel, Well, the blanks that I installed were made for this panel. There is a small gap between the circuit breaker and blank. What if anything can be done about this, any tricks?
 

roger

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Fl
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Contact the manufacturer and tell them what the inspector is having a hard time with, they can send you documentation or help you with a solution. Trying to come up with a non-listed fix might cause you more grief that where you are at now.

Roger
 

jmellc

Senior Member
Location
Durham, NC
Occupation
Facility Maintenance Tech. Licensed Electrician
Sounds like an overzealous inspector to me. Is there enough gap that a finger could get through? Is the blank in danger of falling out?

If you have the right brand and variation, such as Cutler Hammer CH or BR, what else are you supposed to do? I guess you could fire caulk the gap. Maybe you could take the cover to a welding shop and have a piece of metal plate welded in but that wouldn't be UL approved would it?
 

Cow

Senior Member
Location
Eastern Oregon
Occupation
Electrician
Maybe you could take the cover to a welding shop and have a piece of metal plate welded in but that wouldn't be UL approved would it?

If you weld a metal plate in, how will the breakers fit later when you need the spaces?

I would get the manufacturers documentation and pass it along to the inspector.
 

jmellc

Senior Member
Location
Durham, NC
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Facility Maintenance Tech. Licensed Electrician
I was being sarcastic about the BS issues some inspectors come up with but one could cut the plate out with a cutting wheel, I would think.
 

Ponchik

Senior Member
Location
CA
Occupation
Electronologist
Maybe the OP has a filler plate from a different manufacturer than what his panel is.
 

infinity

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Location
New Jersey
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Maybe the inspector was over thinking this part of the requirement:

110.12
(A) Unused Openings. Unused openings, other than those
intended for the operation of equipment, those intended for
mounting purposes, or those permitted as part of the design
for listed equipment, shall be closed to afford protection
substantially equivalent to the wall of the equipment.

Where metallic plugs or plates are used with nonmetallic
enclosures, they shall be recessed at least 6 mm ( 1 ? 4 in.)
from the outer surface of the enclosure.

I never understood how plastic blanks were substantially equivalent to metal.
 

infinity

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New Jersey
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What do you think metal blanks protect against that plastic ones do not?:?

I see nothing wrong with the plastic blanks but I don't see how you can say that they're substantially equivalent to the wall of the equipment when the equipment is metal.
 

jim dungar

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PE (Retired) - Power Systems
I see nothing wrong with the plastic blanks but I don't see how you can say that they're substantially equivalent to the wall of the equipment when the equipment is metal.

You need to read all of the words that are in the section of code you quoted
to afford protection substantially equivalent to the wall of the equipment.
What protection does a metal breaker blank, or knockout plug, provide that a non-metallic one might not? Both metal and plastic can be drilled through and both can also be pierced by a sharpen awl hit with a 5 lb hammer.
 

iwire

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Location
Massachusetts
You need to read all of the words that are in the section of code you quoted
What protection does a metal breaker blank, or knockout plug, provide that a non-metallic one might not? Both metal and plastic can be drilled through and both can also be pierced by a sharpen awl hit with a 5 lb hammer.

You are not seriously proposing that the plastic blank is as tough as the metal it is filling a hole in right?

It would be damn near impossible to drive a sharpened awl through a panel cover yet I can break out plastic blanks with a single soft shot from my pliers.
 
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infinity

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Location
New Jersey
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You are not seriously proposing that the plastic blank is as tough as the metal it is filling a hole in right?

It would be damn near impossible to drive a sharpened awl through a panel cover yet I can break out plastic blanks with a single soft shot from my pliers.


That's my point if you're comparing metal to plastic. I have no problem with using plastic blanks but find the wording of that section to be somewhat fuzzy and open to interpretation.
 

jim dungar

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Location
Wisconsin
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You are not seriously proposing that the plastic blank is as tough as the metal it is filling a hole in right?

It would be damn near impossible to drive a sharpened awl through a panel cover yet I can break out plastic blanks with a single soft shot from my pliers.
I guess the first thing to answer, is whether the protection provided by a hole enclosure is intended to be accidental contact with exposed conductors, maintaining environmental integrity, or something like damage from tools?
Listed general purpose enclosures are allowed to have holes of up to 1/8" and yet still provide protection.
Doesn't a snap-in non-metallic blank offer protection equivalent to an 'unknocked out' knockout, some of which can easily be removed without tools?
 
Would a circuit breaker be considered equipment?


110.12
(A) Unused Openings. Unused openings, other than those
intended for the operation of equipment, those intended for
mounting purposes, or those permitted as part of the design
for listed equipment, shall be closed to afford protection
substantially equivalent to the wall of the equipment.

Where metallic plugs or plates are used with nonmetallic
enclosures, they shall be recessed at least 6 mm ( 1 ? 4 in.)
from the outer surface of the enclosure.
 

sparkyrick

Senior Member
Location
Appleton, Wi
Another solution is to install spare breakers. Depending on what brand/style, (or if you have some old ones laying around), the cost may be negligible.

What will the inspector say about the gap between two breakers?:slaphead:

Walmart makes you take out any spare breaker and install blanks. The last remodel we did, a Walmart Manager took the spare breakers that were sitting in a box in one of the electrical rooms and threw them out, because the electrical rooms can't be used for storage. I can't make this stuff up.
 

roger

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Location
Fl
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Retired Electrician
The only real problem with leaving a breaker in the on position with nothing connected to it is that amps will run out of it and fill the panel up. :slaphead:

Roger
 

GoldDigger

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Location
Placerville, CA, USA
Occupation
Retired PV System Designer
The only real problem with leaving a breaker in the on position with nothing connected to it is that amps will run out of it and fill the panel up. :slaphead:

Roger
That is why you drill an insulated drain hole in the bottom of the enclosure.
In some cases the existing hole for the GEC will do the job. (Since the amps are trying to get to "ground".)
:)
 
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