Re: [CAD_CAM_EDM_DRO] Stepper resistance reading question

I don't think that the current is directly related to the winding
resistance, due to the inductance of the winding. However, it is probably a
significant factor at low speeds. You might try using a Wheatstone Bridge
to zero in on that resistance. Unfortunately, I've forgotten how to set one
up... Somebody???

RayHex

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> From: Jeff Goldberg <jeff@...>

> I've been identifying my steppers (unmarked NEMA 42's mounted on my
> Bridgeport 2J) by comparing the winding resistance to the Sigma

Instrument

> spec sheet I got a hold of. Because in two cases, the resistance was too
> small for my meter to pick up, I've been wiring the windings in series,
> taking the total reading and dividing by four. I just noticed that a

least

> in one case this is not working out (reading across one winding: .2-.3

ohm,

> reading across four windings: 1.2 ohm). I'm using a Fluke digital meter.
> Since this is the only way I have to identify the motors (and use the
> correct current setting), its pretty critical that I understand what's

going

> on.