Question conditions

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hhsting

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I have 1600A 278/480V three phase switchboard in electric room. Their is rack which about 6 feet from that switchboard and in working space. The rack has panelboards 1000A 287/480, 200A panelboards 208/120V mounted on it

My questions are following:

1. Would the switchboard and rack fall under which of the 3 condition Table 110.26(A)(1) if it is metallic?

2. Would the switchboard and rack fall under which of the 3 condition Table 110.26(A)(1) if it is wood?
 
Trick question. The working space for equipment 151-600V to ground is only 4' in the worst case. The rack is behind the switchboard's working space.

In both scenarios, you would be at least condition 2 since you have metal panels on the rack and a metal switchboard enclosure. I would design around condition 3 since you could have exposed live parts on both sides. In all cases, 6' is more than enough space. It would not be enough space in either condition if you needed double the working space to allow for one door into the space.
 
d0nut said:
Trick question. The working space for equipment 151-600V to ground is only 4' in the worst case. The rack is behind the switchboard's working space.

In both scenarios, you would be at least condition 2 since you have metal panels on the rack and a metal switchboard enclosure. I would design around condition 3 since you could have exposed live parts on both sides. In all cases, 6' is more than enough space. It would not be enough space in either condition if you needed double the working space to allow for one door into the space.
Click to expand...

Rack is Not behind the working space. Switchboard is large equipment and so double working space is being used to get single entrance 110.26(c)(2). Now do u see?


In that event double working space would 6 ft be enough and which 3 condition table 110.36(A)(1) for both if rack is metal or wood?
 
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Assuming that the electrical equipment is mounted to the rack and the equipment on the rack is facing the large equipment, the rack has nothing to do with it.
The electrical panels facing each other is always a condition 3 installation.
 
I am kind of confuse. Please see attached picture of what i have. Panelboards on rack are facing switchboard but the piece of rack comes in the way if u have double working space condition #2 or #3 table 110.26(a)(1).
So would 6 ft be enough?

92073f3dfdc5096ade662ca4556eb91e.jpg
 
hhsting said:
I am kind of confuse. Please see attached picture of what i have. Panelboards on rack are facing switchboard but the piece of rack comes in the way if u have double working space condition #2 or #3 table 110.26(a)(1).
So would 6 ft be enough?

92073f3dfdc5096ade662ca4556eb91e.jpg
Click to expand...
Just mark the plans to require the rack to be shorter or moved to towards the bottom of the drawing so there is no issue.
 
hhsting said:
Their is 3000A trough downstream with feeder taps with disconnects 1000A, 600A, 200A etc wonder that can be also large equipment as well no?
Click to expand...
Where is that in the drawing?

Roger
 
We saw that, you were making it sound like there is something else that would change Don's answer.

Roger
 
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