RE: [CAD_CAM_EDM_DRO] Re: Yet another NEMA 42 roadblock

You checked it with the ohm meter to determine which terminals are the
end of coils. That is your sanity check.

Now just connect a pair of coils to the drive, connect the drive to 24
vdc and set the amperage to .5 amp or so and just figure it out. The CMD
drive has a lot of self protection and at 24 V .5 amp you are not going
to damage a NEMA 42 motor, but you sure can verify that it is working
properly. You are not going to be learning anything until you put some
action into trying the motors.

I can't resist asking, are you an engineer by any chance??

Tim
[Denver, CO]
Sherline products at Deep Discount
Mach1 & DeskCNC with credit card ordering
www.KTMarketing.com/Sherline
Now selling Visual Mill

> -----Original Message-----
>
>
>
> I looked at the archives and realized that I may have a Sigma
> (rather than a Superior Electric) NEMA 42 stepper. (Someone
> told me that if the screws are in two lines, like mine,
> rather than in a circle then its likely to be a Sigma).
> Sigma's were apparently used by Bridgeport as well during the
> time my machine was made. As my motors are unmarked, this
> could account for the difference in terminal nomenclature.
> I've been unsucessful in finding any information about their
> motors on the web. Do you know where I can get this type of
> data? (I'm reasonably comfortable that I'm at lest in the
> ballpark on my voltage and current assumptions (2.1 volts and
> 8.5-9 amps based on the motor's resistance of about .28 ohms
> and a number of spec sheets from various manufacturers), but
> I'd like to do a sanity check on the windings before I
> destroy a motor because of my own stupidity.
>
> Any help would be appreciated.
>
> Regards,
> Jeff