Duplicate alarms

Hi all,

I’ve configured some alarms points and a simple pipeline to email notifications out. About 50% of the time I get duplicate alarms for the same condition, and this includes duplicate emails as well. When I dig into it I see that the alarms have the same timestamp but different UUIDs. The alarms are just bits on the PLC and not mechanical or electrical contacts so I don’t think that the signal is bouncing or anything. Anyone have ideas of what to look into to try and remedy this?

I’ve attached an image of an alarms view. Note that the first four alarms on the list are duplicates of two alarms, and the last two on the list are duplicates as well. Also note that the UUIDs are unique between them all.

Somewhat related - when I look through old alarms I can see instances where the duplicate alarms were cleared at the same time, so it seems that Ignition knows about both instances.

Regards,
Charles


1 Like

Hi Charles,

I have seen before where an OPC value may bounce back and forth a moment before settling on the final value, even if the PLC value stays steady. Granted, this was back in the FSQL Days, but I imagine the potential is still there.

Have you tried increasing the Active Delay on the alarm?


Thanks Jordan,
I’ll have to try that, thanks for the tip. Do you know what a good range might be (or what has worked for you)? I can’t see the OPC server flip flopping around for more than a few seconds but I might be wrong.

Charles

I have set my active delays to be a multiple of the scanclass polling rate. It makes sense that 2 or 3 reads in a row of an alarm value would be confirmation of an alarm state. (Assuming of course that’s reasonable)