You need to see whether the output modes of the two PLCs are the same, such as relay output, transistor output and SCR output. , and then see if their output labels are the same, and use the program to monitor whether the PLC program is running and whether the PLC output indicator light is on, which basically solves this problem! And the most important thing is to see if there is an alarm indication in the status of PLC CPU running indicator light.

I hope I can help you!