Best way to detect PLC, sensor disconnection

Hello,

Is it possible to detect the disconnection of a PLC using the prosys OPC Client and Ignition OPC Server?
Is it possible to get callback when the PLC is disconnected?

What about sensor? Is it possible to detect a disconnection of a temperature sensor as example?

Thanks for your advices,

The temp sensor I am not sure about.

You could potentially look at the quality of the tags you are monitoring. You could then alarm off of that. There is also a diagnostics folder that contains a tag called “Connection State”. You could use this as well.

If it is 4-20ma, You can alarm when it is below 4ma.

Thermocouples usually read max when disconnected, can alarm on that.

Depends!