Micrologix 1400 Major Error S:1/13- PID Value Invalid

I recently needed to add a feature to a program which allows the operator to limit the output percent of a VFD controlled 2 HP pump motor.

I achieved this by writing to the PID loop CVL and CVH extensions. I setup some traps to catch the rung causing the issue. However no one is on site to turn on the air compressor so the system will run. I am accessing the system remotely. I am in California, system is in Ohio.

Can someone more knowledgeable than I look at my code? It is in file LAD 10 I/O starting on rung 0026 through 0047. It is called transfer pump P01. Its job is to transfer water from one tank to another. The tank it pumps into has a pressure transmitter and this value is the process variable for the PID loop.

any input greatly appreciated.

Think I found the problem. I need to set limts in the HMI for CVH and CVL to prevent CVH value from being lower than CVL.

Thor Hammer said:

Think I found the problem. I need to set limts in the HMI for CVH and CVL to prevent CVH value from being lower than CVL.

Click to expand...

Check for limits in the PLC also. I don't trust HMI's/SCADA systems.