I bought a stepper motor controller a while a go, a small simple one from Herbach, and recently tried to connect it to a new motor- the chip blew up. I then looked at the info sheet and realized I should have used load resistors (the motor I had on it before worked fine without load resistors). SO I bought a new controller, and before I connect it to the motor, can anyone help confirm what size resistors I should be using? I have two options for the motor:

1. Superior Electric slo-syn motor- 11v DC, .44 amps, 8 wire. I assume this is four coils, so using the formula I received with the controller (Rload = +V-Vcoil/ Icoil) I get (11v-2.75v/ 440) and get 18.75 ohms? is this the correct rating for the resistor? what size wattage resistor should I use?

2 (second option)- 5vdc, 3.5w motor, 8 wire. so that would be (calculating .7 amp because of the watts) 5v-1.25v/700ma= 5.35 ohms? These readings seem very small.


ALSO- on the Superior Electric, I have found the pairs in the eight wires, but how do you figure out the sequence of the coils- trial and error?

Thanks for any help anyone can give. I realize by looking over all the threads that I am asking simple, newby questions, but hopefully someone out there can spare the time.

Thanks in advance...