Hope one (or all) of you folks can give me some guidance.
Situation: I have a 'toy' cnc desk milling machine and the Z axis has always given me problems by missing steps due to friction or ?????. I hope a stronger motor will cure this.
The present motor is a Nema 23 5-wire uni-polar rated at 24 V. & 0.18 A.
I would like to replace it with a larger Nema 23 6-wire uni-polar motor rated at 24 V. & 2 A.
The motors control uses TIP-120 resistors (can handle 5 A ??) and have Ohmite Power resistors (30 W, 5.1 Ohms) which is feeding approx. 0.29 A to the motors.
Looking at some literature on the TIP-120, my understanding is resistors are used to control the voltage to it, which in turn controls the output current.
So it seems if I want to successfully use the larger motor, I need to modify the circuit to feed the motor it's rated 2 A.
My current setup uses a 28 V. transformer with 42 VDC at the rectifier outputs.
Is this sufficient info to advise what size resistors I should use to get 2 A to the motor? I trust this is possible to do?
Thanks in advance for your help, Thermo