Re: [CAD_CAM_EDM_DRO] Stepper motor questions

On Sun, 17 Aug 2003 07:47:49 -0000, you wrote:

>I recently purchased a few of these steppers:
>
>http://www.brigarelectronics.com/Merchant2/merchant.mv?Screen=PROD&Store_Code=BE&Product_Code=100SR
>
>The steppers have no labelling at all on them. From the gummy spot, a
>small label seems to have been removed from all of them. The coils are
>3 ohms each (with ohmmeter lead resistance subtracted). Although the
>claim is made in the ad that they require 6 amps, they are quite small
>(the cube part of the body measures 1.53 x 1.53 x 1.24 inches), and
>when I run these over about 2 amps, they start to overheat. The face
>of the mounting 'diamond' is machined very flat, so heat sinking
>appears to be intended in the design, I guess.
>
>Does anyone know what current these are designed for? Or the actual
>specs on them?

I'm going to go out on a limb and suggest 3.2 volts is fine, but 0.68
amps is probably the actual rating.

I have some 130 in-oz steppers, roughly 4.5 volts at 1.4 amps (Nema
34). These are much smaller. However, dropping the voltage down to
3.2 would give you a roughly 2 amp current rating at 130 in-oz, and
then going to 75 in-oz would about halve that, assuming the same
efficiency.

If all these assumptions prove correct, I'd say no more than 1 amp per
coil. 0.68 sounds like it might be the thing.

Harvey

>
>TIA,
>Grant
>
>