Hi ALL,

Discrete Alarms - while adding them -all the trigger bits are 0. 

Mr_Prof

Hi ALL,

Discrete Alarms - while adding them -all the trigger bits are 0. Why is that? See attached. Also, acknowledgement status tag - what does that mean?

To acknowledge the alarm, you need to toggle the cmd bit from 0 to 1, which can also be done through the PLC. Just keep in mind the acquisition cycle, as it may impact how quickly the acknowledgment is processed.

The status bit provides the following information:

• TRUE: Either there is no alarm or the alarm is present and has been acknowledged.
• FALSE: An alarm is present but has not yet been acknowledged.

You don't really need these words unless you have to acknowledge specific alarms. We use them to acknowledge alarms to a specific valve from a faceplate - local ack. You can use this script to acknowledge all present alarms. If you don't use this and only clear alarm on the PLC you won't see alarm acknowledged but only outgoing in the logs.

About trigger bits I don't know, you can modify them to your liking. TIA won't let you use the same bit from the same word twice anyway.