Re: [CAD_CAM_EDM_DRO] 3 phase motor math

In a message dated 5/16/2004 2:49:21 PM Eastern Daylight Time,
cnc@... writes:
Hi guys,

I have a nice old 3 phase motor I want to hook up to my VFD. I've gone
through all the motions of opening it up and cleaning it a bit, and
checking the resistace between windings and ground, and it seems okay.
What I don't know however is whether it's wired right..

My VFD outputs 220V, so I'd need the motor to be in the Delta
configuration.
The motor has the following written on it:

Volts: 220/380-415
Amps: 3.45 / 2.0

I measured 25ohms between each connection point...
But the usual V=IR formulas totally don't yield me any answer.. it must
be because it's 3 phase and AC.

I Googled for 3 phase motor/resistance/amps formulas but only came up
with a lot of junk people were trying to sell me, and some other stuff.
How do I work out what voltage this motor is currently configured for?

Thanks!
-Abby


[Non-text portions of this message have been removed]
This is apparently a European motor as it has 380V on it as well as the 230
or 220. If it has a 6 terminal terminal block on it, wiring for Delta will be
easy.

Let us look at the terminal block as below:

1 2 3

4 5 6

Without removing any of the wires between this terminal block and the
windings in the motor you would simply connect 1 to 4, 2 to 5, and 3 to 6 with
jumpers. Then you can bring in the 3 phase power lines to 1,2,3 OR 4,5,6. If it
runs in reverse to what you need, simply switch any two incoming wires to
reverse it.

I hope this helps.

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.


[Non-text portions of this message have been removed]