## Can a 500v/3ph motor be rewired for 220v/3ph?

### Can a 500v/3ph motor be rewired for 220v/3ph?

I have just bought an ancient Robot Machine Company (NY) surface grinder.
It has a large GE motor rated at 500v 3 phase.   I would like to be able to
run it on my 220 volt 3 phase VFD.   Is it possible that I can locate the
star point in the winding and bring out the other 3 leads to set it up in
delta, or is it most likely already wired in delta, for 500 volts?

What would I look for on the windings?   I have had a quick glance, and
nothing obvious leaps out.   Would the star point (if there is one) be on
the opposite side to the leads that come out of the motor?

Any help would be appreciated.

Regards,
Nick Alexander

### Can a 500v/3ph motor be rewired for 220v/3ph?

nope, once past 440v your stuck.

Quote:
> I have just bought an ancient Robot Machine Company (NY) surface grinder.
> It has a large GE motor rated at 500v 3 phase.   I would like to be able
to
> run it on my 220 volt 3 phase VFD.   Is it possible that I can locate the
> star point in the winding and bring out the other 3 leads to set it up in
> delta, or is it most likely already wired in delta, for 500 volts?

> What would I look for on the windings?   I have had a quick glance, and
> nothing obvious leaps out.   Would the star point (if there is one) be on
> the opposite side to the leads that come out of the motor?

> Any help would be appreciated.

> Regards,
> Nick Alexander

### Can a 500v/3ph motor be rewired for 220v/3ph?

500 volts, 3 Phase, 60 Hz is an odd voltage.  460 or 575 would be standards.
500 volts is a standard DC voltage, however.  I am assuming you do have an AC
motor.  In my experience, the chances are a lot better than 50:50 that the
motor is already Wye or star connected.If you could reconnect it to Delta, that
would make the equivalent line voltage 288 -- perhaps close enough to run on
230 volts without a significant loss of torque.  Even for an experienced motor
winder, reconnecting an old motor is "iffy" since the insulation components
tend to be hard and brittle.  If you don't know what you are doing, I would not
suggest trying it.  If you take it to a motor rewind shop, they may be able to
reconnect it -- or they can certainly rewind it to the voltage you want.
Personally, I would look for a transformer.

Mill

Quote:
>Subject: Can a 500v/3ph motor be rewired for 220v/3ph?

>Date: 18/11/2001 16:11 Eastern Standard Time

>I have just bought an ancient Robot Machine Company (NY) surface grinder.
>It has a large GE motor rated at 500v 3 phase.   I would like to be able to
>run it on my 220 volt 3 phase VFD.   Is it possible that I can locate the
>star point in the winding and bring out the other 3 leads to set it up in
>delta, or is it most likely already wired in delta, for 500 volts?

>What would I look for on the windings?   I have had a quick glance, and
>nothing obvious leaps out.   Would the star point (if there is one) be on
>the opposite side to the leads that come out of the motor?

>Any help would be appreciated.

>Regards,
>Nick Alexander