Help with driver and Stepper

[Bryanpl]

All:

Having trouble getting the stepper to draw more than 500ma using the Rorze driver (pdf's attached). I have tried all combinations of coil configurations, half coil, full coil, series, parallel along with different resistor sets and I can not get the motor to draw more than 500ma. Have tried as low as 0.5 ohm resistor sets but no luck.

Seems full coil in series seems to give me the best low speed torque, but not enough for my application. Need to push the driver to 1.0 -1.5 amps for it to work.

Any suuggestions, or am I doing something wrong. Have tried a L298 driver and it works, pushing the motor to 2amps, but would prefer to use the Rorze, if I could get it working properly.

[vger]

What voltage are you using on the driver? What is the resistance of the motor coil?

Steve

[Bryanpl]

Driving with a voltage of ~26v DC. Two OEM steppers, but they have slightly different windings. One has 1.7 ohms per coil the other 2.4 ohms per coil.

[vger]

Double check your dip switch settings... 1 & 2 ON, 3 OFF, 4 ON.
Did you see the little referance note at the bottom of page 11, and the function 15-1 in the middle of page 13 in the Rorze manual?
Also, I am assuming you are using at least 3 watt resistors.
The type of meter you are using to measure the current may be an issue. When measuring pulsed DC (which is what is applied to the motor) some digital meters can give bad readings.

Good luck

[Bryanpl]

Yes, the DIP switch settings are correct. I was wondering perhaps if the Rorze was somehow detecting a auto shut down condition, but would think the frequency would need to be below 3hz for that to happen.

Meter could be out, but just from the feel of the stepper it is not being driven to 2 amps as my L298 configuration easily does. Perhaps the current resistor calculations in the manual do not apply to my stepper. Going to try a 0.1 ohm resistor this weekend and see what happens.