Re: [CAD_CAM_EDM_DRO] 3 phase motor math

In a message dated 5/16/2004 3:22:36 PM Eastern Daylight Time,
cnc@... writes:
But I was just hoping I could work from the 25 Ohms value to calculate
if it's already in delta, to save all the hassle. Do you know the
formula for this?
For starters, 25 ohms is a LOT of resisitance for motor windings. Usually
they are less than 10 ohms. That alone may help as since it is high, I would
think it is wound Y for the high voltage connection, 380V 50 Hz.

As motors differ from manufacturer to manufacturer, I don't know of any catch
all formula you can use and have only the resistance as a reference.
However, give the link below a try and see if it has anything than might be helpful.


Typical Connection Diagrams - 3 Phase Motors

I don't know if they will have anything that will help but maybe there is
something there which will. The only real way I know is to take apart the motor
so you can see how they have wired it internally. Although, based on the
resistance between leads you mentioned I would lean toward a Y or Star as they
often call it. And that would mean it is wound for 380V 50 Hz.

Randy Abernathy
4626 Old Stilesboro Road NW
Acworth, GA 30101-4066
Phone / Fax: 770-974-5295
Cell: 678-772-4113
E-mail: Cnc002@...

I furnish technical support, repair, and other related services for your
industrial woodworking machinery. My background as Senior Service Engineer for the
SCMI Group for nearly fifteen years with factory training, combines with my
extensive background in electronics, mechanics, pneumatics, electrical and CNC
machinery to offer you needed support for your machinery.


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