Stepper Motor using PLC

Hi!

I am doing my thesis right now and I need some help. =)

I have a linear positioner/actuator ball screw type which is powered by a stepper motor 2phase, 2.5V, 3A.

Now I want the stepper motor connected to PLC (Siemens: S200), can that be directly connected or do you still need a driver? Sorry Im new with stepper motors.

Thanks =)

Hi,

Ideally you would require one of these:

https://www.automation.siemens.com/...er/s7-200/function-modules/Pages/Default.aspx

I have driven a stepper motor from an S7-300 plc but the performance was not terrific. Regular transistor / fet outputs are restricted in the current capability (about 100mA I think) and they will supply +24V DC. I made a mosfet dual H-bridge and connected that to the PLC so that it could drive my +12V / 400ma per phase stepper. Regular PLC digital output cards have fairly slow switching times and this limits the frequency at which you can drive your H-Bridge / stepper.

You could use relay outputs provided your particular S7-200 has that capability, this would allow you to drive the stepper directly at lower voltage and higher current but relays are probably not the best way to be switching highly inductive stepper windings anyway. And the switching frequency will still be poor, probably slower than the transistor output version.




AB