MCCB Enclosure

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Depends on whether it needs to be simply accessible or readily accessible. If the latter, no... IMO.
 
It is for a main circuit breaker of pad mounted transformer outside a buiding and the enclosure is beside of the transformer.

Tom
 
AFAIK, no requirement for that particular use to be readily accessible.

Are you aware an 'in sight of' disconnecting means for a transformer is not required. You can have a remote disconnect provided it is lockable. See 450.14 for details.
 
Perhaps i'm not explaining myself, this is the one line diagram:
One line diagram.jpg

Is there any code violation with 110.27??? taking into account that you have to open the enclosure to operate the MCB and there are the lugs of the breaker.

Tom
 
The NEC would not generally be against this installation. It does not specifically address the construction of equipment like this.

But seriously how much money are you saving trying to do this yourself rather than simply purchasing a standard enclosure designed specifically for this purpose?
 
jim dungar said:
The NEC would not generally be against this installation. It does not specifically address the construction of equipment like this.

But seriously how much money are you saving trying to do this yourself rather than simply purchasing a standard enclosure designed specifically for this purpose?
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None really, if it is done this way you have a lot more space inside the box for the cables, and the electrical inspector, keeps saying that there is a code violation if it is done this way, but I can't find where is the violation, hence i'm asking here.
 
tomito said:
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Is there any code violation with 110.27??? taking into account that you have to open the enclosure to operate the MCB and there are the lugs of the breaker.
...
Click to expand...
Much better explanation. :D

The answer to the quoted question is yes.

And the disconnect as depicted is required to be readily accessible [225.32 or 230.70(A)(1)].

Perhaps you should just use the enclosure that is made for that breaker. See page 76 of...
http://download.schneider-electric....=6498725276&p_File_Name=0100CT1501_SEC-07.pdf
Enclosures are a bit pricey for all the more they accomplish... but there is little alternative when it comes to wet locations.
 
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tomito said:
None really, if it is done this way you have a lot more space inside the box for the cables, and the electrical inspector, keeps saying that there is a code violation if it is done this way, but I can't find where is the violation, hence i'm asking here.
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It's not a violation until you open the enclosure when energized. ;)



And OSHA will have several thousand words for you if you do so without proper PPE. :happyyes:
 
Smart $ said:
Much better explanation. :D

The answer to the quoted question is yes.

And the disconnect as depicted is required to be readily accessible [225.32 or 230.70(A)(1)].

Perhaps you should just use the enclosure that is made for that breaker. See page 76 of...
http://download.schneider-electric....=6498725276&p_File_Name=0100CT1501_SEC-07.pdf
Enclosures are a bit pricey for all the more they accomplish... but there is little alternative when it comes to wet locations.
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230.70(A)(1) readily accessible only refers to location not to the access of the MCB or i'm interpreting the code wrong?

Smart $ said:
It's not a violation until you open the enclosure when energized. ;)



And OSHA will have several thousand words for you if you do so without proper PPE. :happyyes:
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In this case you will have the line side lugs energized no matter what, unless you shut off the transformer.
 
tomito said:
230.70(A)(1) readily accessible only refers to location not to the access of the MCB or i'm interpreting the code wrong?
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You are correct... but a little deductive reasoning reveals there is little purpose in it being located in a readily accessible location if you cannot operate it without donning PPE. See the Article 100 definition of Accessible, Readily .

In this case you will have the line side lugs energized no matter what, unless you shut off the transformer.
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But the made-for 3R can has a dead front through which the breaker handle can be operated without exposure to the line-side lugs.
 
You can get an external rotary handle for these kind of breakers for not a lot of money. Personally I think you would be better off just buying the enclosure from the circuit breaker manufacturer. They all make one are there Breakers in every time I've looked at the pricing it's cheaper to buy the breaker enclosure than it is to try and make something because I would try to make it if it was cheaper. Of course a lot of this depends on how much you are paying for some of these things and that varies so widely it's hard to to know just what might be cost-effective for you.
 
Smart $ said:
You are correct... but a little deductive reasoning reveals there is little purpose in it being located in a readily accessible location if you cannot operate it without donning PPE. See the Article 100 definition of Accessible, Readily .


But the made-for 3R can has a dead front through which the breaker handle can be operated without exposure to the line-side lugs.
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You may be right Smart $, I just wanted to know the reasoning behind the no complaint with the code, I appreciate your answer and the time you took to answer.

petersonra said:
You can get an external rotary handle for these kind of breakers for not a lot of money. Personally I think you would be better off just buying the enclosure from the circuit breaker manufacturer. They all make one are there Breakers in every time I've looked at the pricing it's cheaper to buy the breaker enclosure than it is to try and make something because I would try to make it if it was cheaper. Of course a lot of this depends on how much you are paying for some of these things and that varies so widely it's hard to to know just what might be cost-effective for you.
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Thank you petersonra for the recommendation, I'll take it into consideration.
 
Smart $ said:
But the made-for 3R can has a dead front through which the breaker handle can be operated without exposure to the line-side lugs.
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Of course the OP could fabricate his own internal deadfront. TH OP said the voltage was only 208Y/120.

Most outdoor disconnect installations, <250A, require the equipment door to be opened. Think about meter centers and AC 'pullout' style disconnects.
 
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jim dungar said:
Of course the OP could fabricate his own internal deadfront. TH OP said the voltage was only 208Y/120.

Most outdoor disconnect installations, <250A, require the equipment door to be opened. Think about meter centers and AC 'pullout' style disconnects.
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I'm not against fabricating a deadfront or installing an external operator.
http://static.schneider-electric.us...itches/Door Closing Mechanisms/9420CT9701.pdf

Opening a door is one thing. Being exposed to relatively non-finger or common tool safe energized parts is another.
 
tomito said:
Something like this is what I meant.... :blink: View attachment 17398
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I would consider using something like that only if fitted with add-on shields to cover the terminal areas and make an effective dead front device.

The only problem that would leave is that you would still be subject to arc flash hazard, depending on the voltage and fault current, and that may still make the setup impractical if anyone other than a qualified person with PPT needs to access it.
 
GoldDigger said:
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The only problem that would leave is that you would still be subject to arc flash hazard, depending on the voltage and fault current, and that may still make the setup impractical if anyone other than a qualified person with PPT needs to access it.
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A Power Point file (PPT) will do them no good... :slaphead:

(I believe you meant PPE. :D)
 
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