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New Pump Connection

New Pump Connection

New Pump Connection

(OP)
I have an Emergency Panel 480/277 V 3 Ph,4 Wire,60 HZ . It has in outgoing 3ph 4 wire breakers connected. I need to purchase a new de watering motor of 1 HP & to give power from this panel.
1. Can i connect 1 phase also from the outgoing 3 ph breakers.
2. The voltage for 1 phase is 277, so will 230 V 1 ph will be suitable.

thanks

RE: New Pump Connection

Please buy a three phase, 460 volt motor.
You other option will be to purchase a 480V:240V transformer and run a 230V single phase pump.
No, 277V is not quite the same as 240V. That;s why they call one 277V and the other one 240V.
Supply voltages are multiples of 120V.
Motor voltages are multiples of 115V.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: New Pump Connection

And if it is an "emergency" panel you need to check the rules in Articles 700 and 701 in the NEC to see if you are permitted to connect that load to the "emergency" panel.

RE: New Pump Connection

I agree with previous responses.  Get a 460 V motor, or put in a step-down transformer and use a 230 V or 208 V 3-phase motor.  If this is truly an Emergency panel per NEC definition, it's no place to go with some jury-rigged solution to a non-existent problem.  

Yes, the 460 V motor will be more expensive.  Just deal with it.

 

David Castor
www.cvoes.com

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