We are building a small linear actuator using stepper motors. We have tried the following combinations to drive an 7/8" ACME thresded rod and nut and find them all underpowered. The device is a lever system to lift 500 lbs.
(All NEMA 34 frames)
640 oz stepper motor with 12/1 gear reduction (8 wire, wired bipolar serial)
1200 oz stepper motor mounter direst (w/o reduction) 4 wire
1800 ox stepper motor with 3/1 gear reduction (8 wire, wired bipolar)
Power supplies we have tried are 24V5A, 48V5A and 48V7.8A
range of motor RPM is 0-30, maybe 45
We have a number of drivers from Keling and Anaheim Auto (5A to 10A). and can't seem to get enough power no matter the step options set (1/2 step thru to 1/64 step).
An amp meter placed between the power supply and the volt input to the driver reads, generally, something between .8 and 1.8A. Stalling the motor provides the higher (1.8A) reading.
By all our math and torque calculations any of the above combinations should work. We are thinking of going to 80V to see if that makes a difference. Any suggestions would be helpful.