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#129338 - 01/23/05 10:22 PM ph 3 wire delta to supply 3ph 4 wire y
splitzapper Offline
Junior Member

Registered: 01/21/05
Posts: 6
Loc: Davao
hello there. the electrical utility that serves our place supplies a secondary of 240/208v 3ph,4 wire Delta.will it be ok if a 4 wire, y motor be supplied by this? is it safe if i put the common wire of the motor on the ground wire of the delta supply? What would happen if i do this?

thanks again.....
Oh Yeah!

#129339 - 01/24/05 06:42 AM Re: ph 3 wire delta to supply 3ph 4 wire y
pauluk Offline

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
Is the motor designed for a wye connection to 120/208 volts?

You won't be able to connect directly to the 4-wire delta (the high leg will be 208V to neutral, and the phase angles will be wrong anyway).

#129340 - 01/24/05 06:49 AM Re: ph 3 wire delta to supply 3ph 4 wire y
JBD Offline

Registered: 07/12/01
Posts: 599
Loc: WI, USA
The utility supply voltage is probably 240/120 3 phase 4 wire delta.

The internal construction (winding arragnement) of a motor is not a factor. all you need to worry about is what external connections (leads) are provided.

If you only have 3 voltage leads (one per phase) then your motor will work fine. If you need 4 wires to your motor (extremely rare) it will not work on your 4 wire delta service.


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