clear work space

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ray tieman

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we have a 1000 amp main switch board (nema 3r) , in an outdoor concrete enclosed area with no ceiling. The lockable doors open 90-180 degrees,with them open we meet art 110.26 (151-600 volt ) condition 2 , (we have 48" to the deadfront). The nema 3r portion of the enclosure is 9". With the doors closed we have 39" to the concrete wall behind, would the n3r portion count ? The doors have to be open to service.
 
The measurements should be taken from the front of the switchboard/ panelboard and not from the doors to the enclosure IMHO.

Chris
 
If with the doors open, you have adequate working clearances, then you meet the code requirements. There is no need to also have clearances with the doors closed.
 
Let me backtrack a moment. Perhaps I don't understand your description. What doors are you talking about, when you say "lockable doors"? The doors to the equipment, or the doors to the room?

I had thought you meant doors to the room. Chris' response makes me wonder. If you mean doors to the equipment, and if the room has only 39 inches from the front face of the equipment to the wall, and if you are saying that you have 48 inches from the concrete wall to the back of the equipment, then I agree with Chris: you have a violation on your hands.
 
Charlie I think what he is discribing is a Nema 3R exterior switchgear in an enclosure with doors that must be opened to access the switchgear inside.

Chris
 
the lockable doors are the nema 3r part of the enclosure. concrete wall behind to these doors = 39", concrete wall to the dead front within the enclosure = 48" .
 
In my opinion, as long as you have the proper working space clearance between the deadfront and the concrete wall you are OK.

Chris
 
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