Two doors for electrical room - 110.26(C)

[anbm]

Electrical room: we have 1,200A MLO distribution panel, this panel is protected by 1,000A CB in upstream panel.

Do we have to follow 110.26(c) rule so the room need to have two entrance doors? ... Or one entrance door if panel satisfy double clrearance requirement?

Since the panel is protected by 1,000A CB, we can consider panel rating is1,000A not 1,200A right? Then, we may need only one door for the room. I am not sure if panel is wider than 6', could be less than that. This will be another support factor?

 

[charlie b]

The relevance of the 6 foot width will depend on which code cycle applies to your project.

I had this very discussion (i.e., disagreement) with an inspector last month. He required two doors, and the space could not possibly accomodate two doors. His stance was essentially, "in this jurisdiction, our interpretation is . . . ." What made it particularly interesting is that the drawings and specs called for a 1000 amp board, and the contractor purchased the 1200 amp board. The solution: the inspector signed off on the installation after we had the manufacturer's representative come to the site and relabel the board as having a rating of 1000 amps.

 

[Pierre C Belarge]

The NEC does not specifically require DORRS.

The ENTRANCE to the work space is what is required.
There is a dramatic change to the '08 NEC in regards to the distance. So it is important as to which code cycle you are referencing in your jurisdiction.

 

[steve66]

Since the panel is protected by 1,000A CB, we can consider panel rating is1,000A not 1,200A right?

I'm not sure that is the case. I think the code says "equipment rated 1200 amps or more.." Even if you protect the equipment at 1000 amps, IMO, it is still rated at 1200 amps.

Steve

 

[charlie b]

Even if you protect the equipment at 1000 amps, IMO, it is still rated at 1200 amps.

That is why the inspector in my story allowed us to get the panel label changed to a 1000 amp rating.

 

[steve66]

That is why the inspector in my story allowed us to get the panel label changed to a 1000 amp rating.

I think he made the right call, but it sure seems weird. We all know the 1000 amp labels aren't any less dangerous than the 1200 amp labels

Steve

 

[cowboyjwc]

That is why the inspector in my story allowed us to get the panel label changed to a 1000 amp rating.

We had a contractor do the same thing.

 

[weressl]

That is why the inspector in my story allowed us to get the panel label changed to a 1000 amp rating.

Thereby voiding the UL listing.

The inspector has no authority to change the label, but he can require the posting of the sign: This panel is suitable for 100A service only as per the .........(Insert AHJ ID).

 

[skeshesh]

Label

Label

The inspector has no authority to change the label

we had the manufacturer's representative come to the site and relabel the board as having a rating of 1000 amps.

The inspector had not authority and did not change the label, but I don't see why the manufacturer's rep can't do this.

 

[cowboyjwc]

The inspector had not authority and did not change the label, but I don't see why the manufacturer's rep can't do this.

We checked with UL and as long as the rep did it, it was acceptable.

 

[charlie b]

The inspector has no authority to change the label. . .

In case I wasn't clear, the manufacturer's representative came to the site to replace the label, after which the inspector was satisifed that we no longer met the criteria for needing two exits from the working space.

 

[weressl]

In case I wasn't clear, the manufacturer's representative came to the site to replace the label, after which the inspector was satisifed that we no longer met the criteria for needing two exits from the working space.

Correct, you were not clear.

I am not certain that the manufacturere had the authority either to change a lable that was approved by a third party agency. Once that third party agency permitted his approval or listing seal to be on the label, any changes must be done with the third party's knowledge and approval. (If they had a-priory blanket approval to do so, then it would be OK.)