Stepper clock output not correct

[stefan]

I have a program that drives a stepper motor. it works fine on the simulation - ie generates the expected speed and direction. When I try to it on the PLC, the clock frequency is nowhere near where it should be- and the motor turns at around 30pps if set at 10 or 20 or 50 or 70 etc.. This occurs even if the motor and driver is not connected  and I measure between the positive and output 5 When asking for higher pulse rates, say around 200 + I get around 110 or so. This occurs even if the motor and driver is not connected  and I measure between the positive and output 5.

[support]

The stepper motor output on T100MD+ or T100MX+ are only an approximation. The purpose of the stepper motor output is for position control and not for performing precise frequency output. The stepper output is generated using timer interrupt and the actual pps is limited by the timer resolution.

If your purpose is for generating precise frequency output then the T100MD+ PLC is unsuitable for such purpose.

I believe the upcoming F-series PLC can generate more precise stepper motor frequency or PWM output with continuously variable frequency. It is not yet officially released but you can contact sales@tri-plc.com to inquire about availability.