Hello..., im struggling with my three-phase WEG drive stopping before the PLC timer runs out. I am a final year electrical engineering student and my project is a PLC-based control system for a three-phase induction motor. I have to control the speed of the motor on any load condition. I have five different rpms im testing the motor on and have a timer in the program that counts down the time the drive should keep the motor on the reference setpoint value. I am using a inductive proximity switch to count the pulses per second so my program can chase the reference frequency. I think the problem is in the drive, any suggestions please?

 

Are you attempting to position a induction motor with a VFD & PLC?
More details of the operation are needed, but the mention of a reference set point indicates a positioning application?
Max.