motor missing nameplate 1

[skipr5]

Some guy from Sweeden opened up a shop in California. He brought some of his machine tools with him. I was asked how to get his Pullmax machine to work. The motor has no information at all. Its been painted several times, the plate is gone but the rivets remain. I tried to cross reference the frame size in NEMA and IEC. No matches. The way this motor mounts has to be exact match to the rigid frame mounts. All I can guess by opening motor is that its 3 phase, 6 poles. It only has 6 leads with no markings. I'm guessing 380 volt 50 hz. The system he is trying to run it on is 120/208 volt 60 hz. The motor worked fine in Sweenden (he claims). Any ideas on what I could do since I have to use this frame?

 

[waross]

That is a reasonable assumption, but I may be corrected by one of our IEC experts. In delta, at 60 Hz, the rated voltage will be 264 volts. In star, at 60 Hz the rated voltage will be
456. In the old days this would be transformer time.
But first, have you evaluated the performance of the machine at 60 Hz? The machine-motor combination may not be suitable at the increased speed.
These days, go for a VFD. I see many machines with oversized motors so it should run on the slightly lower voltage.
If not, try this;
A 240:12 Volt boost rated transformer will jack 208 volts up to 218 volts. Connect two transformers in open delta. One fro "A" to "B" and the other from "A" to "C". This is called an open delta autotransformer configuration. I have used the circuit many times running 460 volt motors on 600 Volts and 550 Volt motors on 480 volts.
Sizing;
The 12 volt winding of each transformer must be capable of passing full phase current of the VFD.
It's that simple.

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

 

[zlatkodo]

If the motor power is low, best solution is rewinding on new voltage and frequency . Of course, you must be sure for what speed is motor intended.. Take a look:

http://www.youtube.com/watch?v=guPfSCPNiZI

Zlatkodo

 

[ScottyUK]

You might want to contact Pullmax over on your side of the pond to get their input:

Pullmax Inc.
2255 Lois Drive, Unit # 1
Rolling Meadows
IL 60008

Phone. (847) 952 9977
Fax. (847) 952 9988
Toll-free: (800) 255 0502
E-mail: info@pullmaxinc.com


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