Automatic Transfer Switch Location Requirements

[mjaenke]

On a recent hotel Job, my electrical drawings were disapproved saying that the Automatic Transfer Switch needed double the clearance in the electrical room. Up until now i assumed that the transfer switch needed 3.5' in front to comply with NEC art. 110.26. If i'm reading art. 2002 NFPA 110 7.2.2 and 7.2.2.1 correctly, the transfer switch was allowed to be installed in the main electrical room IF double the distance was provided. The 2005 NFPA took out this exception. I cannot find any article in the NEC that talks about where to mount or clearances for transfer switches. Going with the information i have, am i forced to assume that transfer switches cannot be located in the same room as other service equipment? Why???

Thanks,

Matt Jaenke

 

[DonPhillips]

The disapproval should have quoted the code section that the ATS was not in compliance with, if the review was by a code enforcement agency. Otherise, if it was a shop drawing review by the EOR, perhaps there is something in the specifications, perhaps a reference to another standard.

Don Phillips

http://worthingtonengineering.com