RedLion ModController Communication

Is there a way to detect active communication between a plc and a redlion mod control? I need to disable my heat controls when the communication between the mod control and plc are interrupted. Normally I would use a heart-beat timer between two PLCs, but that doesn't appear to be a viable option here.

What Redlion Controller are you using? I think all of those controllers run Crimson, so you should be able to write a script to do the heartbeat. Write a number to the Redlion, have it read the value, increment it by one and write it to a different location where the PLC can read it back.

I like to use the IsDeviceOnline() command. It works really fast.