Newbie- Vexta PK266-01A - Are these good?

[nuclearice]

I just found a set of 4 vexta pk266-01a-c23 motors on ebay for $25 and wanted to see if they are worth it. I am building a modified jgro that is slightly smaller than the plans call for and have 1/4-20 threaded rod but want to return that and move up to 1/2-10 acme. Will these motors serve me well? The specs are:
(bipolar series)
166 oz*in
.71 A/phase
40 mH/phase

I will be driving them with the new Gecko G250's @ 48V. If any more info is needed I'll be happy to supply it. Thanks!

[Richards]

The limiting factor with the PK266-01 stepper motors is the inductance. At 40mH, you would need a power supply producing about 200 V (using the formula 32 X SQRT(inductance) = MAX voltage).

If I remember correctly, the G250 likes stepper motors that have inductance around 2.5mH.

Even if wired half-coil, you would need about a 100V power supply to get the most out of those motors. Even the full power G201/G202/G203v stepper drivers are limited to 80V and the G250 is limited to 50V.

I have used a lot of the PK268-02A stepper motors, wired half-coil with both the G202 and the G203v stepper drivers. The inductance for that motor, when wired half-coil, is 3.5mH, which gives a maximum voltage of about 59V. Running that motor at 50V or slightly less, with the G250 might be a good combination.

The PK266-02A motor is rated at 2.5mH, which would make it an ideal match for the G250 (voltage wise); however, keep in mind that it only has about 125 oz*in of holding torque.

[nuclearice]

Thanks, that was very helpful!