How to detect PLC failure

Ignition
7

Hi All,

Thanks for the reply.
I am using a bit of code in PLC to go 1,0 every sec when the PLC is healthy.

PLC_HeartBeat%20logic
PLC_HeartBeat%20logic1449×348 6.92 KB
.

Then I am using an expression tag with the following expression -

if(hasChanged({[.]PLC_Heartbeat}),1,0)

This tag is set as an alarm to flag up when the heartbeat is not healthy and I have set it to a 'clock' scan class.

I have tested it and this seems to be working fine with following errors -

  1. Any minor/major PLC faults.
  2. PLC network/comms error.
  3. Connecting/Disconnecting Device status in Ignition.

I guess its a round about way of getting it working. But seems to be giving me the result that I want. :slight_smile:

Thank you all for help and direction.