Re: [CAD_CAM_EDM_DRO] stepper motor winding testing

At 14:12 30/04/2003 +0000, you wrote:

>Hello group. I have an unmarked stepper motor, I believe to be a pac
>sci p22. It has 8 pin connector on top, and I would like to verify
>the windings are good or bad. Does anyone have any suggested
>procedures?

8 wire motor, therefore there should be four electrically independent
windings, each with closely similar electrical resistance. So:

- Work out which pairs are which (simple continuity tester will do this).
If you haven't got 4 distinct pairs, then there is a problem (for example,
3 pairs + 2 wires apparently unconnected would lead you to believe that one
coil has gone open circuit; 3 or more wires that have a measurable
resistance between any chosen pair would lead you to believe that two or
more coils are shorted together).

- If you have 4 separate pairs, measure the electrical resistance of each
coil. For this you will need a resistance meter that will potentially
measure sub-1 Ohm resistances. The coil resistances should be very similar
(and not zero!). If they are not similar, one or more coils could have
shorted turns. If you have a spec for the motor, the measured resistance
should of course be close to the spec value.

If these tests pass, you probably (but not certainly!) have a working motor.


Regards,
Tony