panelboards

[davidselectrical]

I am installing a CNC router for a customer which draws 140 amps at 240 volts 3 phase. (At 480 volt 3 phase it draws 70 amps)

We need to install a sub-panel to feed the new machine and for additional future equipment.

The customer is planing to upgrade their existing 120/240 volt 3 Phase service to 277/480 volt 3 phase.

No wanting to purchase equipment that will not be compatible to the new voltages I would like to install a 277/480 volt rated sub-panel.

Would there be any reason that the 277/480 volt panel could not be used at 120/240 volt 3 phase?

 

[infinity]

So you want to use the 480Y/277 volt panel with a 120/240, 3?, 4W Delta system?
Take look at this recent thread:

http://forums.mikeholt.com/showthread.php?t=142660

 

[jim dungar]

Fast answer: most manufacturers allow their 480Y/277 panels to be used on 240/120 delta systems, but the breakers will have different AIC ratings.

 

[davidselectrical]

thank you...

that's is what I figured would be the case.

(as long as the panel is clearly marked that it is wired at a lower voltage)