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Schneider Electric M221 Pump Program
Problems programming analog PID

Very new to the programming side and recently was tasked with writing a basic level control vfd start/stop program. I seem to be having an issue of having the drives start when the high level has been reached in the SoMachine Basic program. The level transducer is outputting its milliamp signal to the PLC, but I am not seeing anything in the PID rung. This would seem to be the culprit for not allowing the drive to start.

First you should check VFD input that can control by external switch or not. Then check sensor output that in type 4-20 mA and it connect to PLC analog card.

I think this system PID are control by VFD not PLC, that why you don't see any PID configuration in PLC.

Check the start sequence requirements for the vfd. If there is an enable (or STO) and run input, the vfd may require enable active before run is activated to allow rotation.