I'm designing a project where a 1500kw generator will be installed to provide back-up power for a 200,000 sqft office building. The xfer switch will be installed about 30' from the main gear and I want to use cable tray with single conductors so I can get the ampacity rating of open air and the electrical contractor will have fewer cables to make-up but the NEC says this type of installation is limited to industrial occupancies only per 392.3(B)(1). The electrical rooms are in a maintenance area of the building this is locked at all times and is only accessible by qualified persons. Any info on a variance and will the AHJ allow this installation?
Any help is greatly appreciated.
Any help is greatly appreciated.