577 volts to 480volts?

[harveytonely]

We are running 480 volt 3 pahse at our facility. We found a deal on a piece of equitment we need,but the motor is wound for 577 volts. Would it be alright to run this motor at 480 volts and expecting slightly more amp draw?

 

[dpc]

Probably not. That's a big difference in voltage.

If you are getting such a good deal, you'll be able to buy an autotransformer with all that extra money and boost the voltage up to what it should be.

 

[harveytonely]

Yea ,I could do that but I have a very small inside cabinet that is aleady loaded with no room. Besides that everything else is 480 volts so it might confuse someone after me, especially if a nameplate got to missing. If it would be a big problem I would just have the motor rewound. Thanks for the reply.

 

[dpc]

The autotransformer is a good solution - much less costly than trying to rewind the motor. But whatever you think.

Pretty sure you won't be happy running the 577 V motor at 480 V.

 

[waross]

Post the motor rated Full Load Amps at 577 Volts and we can show you a sample transformer size. The transformers may be much smaller than you suspect. I have encountered this issue a lot. I typically mount the transformers close to the motor. Is this a 60 Hz motor?

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

 

[zlatkodo]

Every time you ask something about motors, you need to write all the details from the nameplate..
Zlatkodo

 

[edison123]

It will be cheaper to rewind that motor to 480 V.

 

[waross]

Sample calculation;
Motor current = 5 Amps
Boost needed = 120 volts
KVA = 5A x 120V / 1000 = 0.6 KVA
For this example motor you would need 2 boost rated 480:120 Volt transformers connected in open delta auto-transformer boost configuration. Dry type transformers may be mounted outside a panel or control enclosure. I have mounted them on the floor beside the motor at times.


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