Alarm Synchronization Between Two Gateways

Ignition
1

Let’s say I have two gateways with identical tag providers, getting their data from the same source. Each are looking at the same tags with the same alarm configuration.

If I ack an alarm on Gateway 1… what’s the best way to ack it on Gateway 2?

Also, if I ack’d an alarm on Gateway 1 while Gateway 2 was offline, how can I tell Gateway 2 about it when Gateway 2 comes online? (Assuming the alarm condition is still active)

I could…

  1. within alarm ack script, search through the other gateway as a remote tag provider for a tag in alarm with the same tag path and remotely ack it. and in the startup scenario i’d hold off on all alarm presentation until I go through the remote provider one by one to match my local acks (though this could be problematic with alarms that have long delays)

  2. maintain a separate centralized alarm database that both gateways check every 1 second

  3. ???

Open to suggestions.

2

I would say you’re going to have a much better time if you have a single tag provider, and ‘share’ it via remote tags to the other gateway. Is that not an option for some reason?

1 Like
3

Not allowed to have any dependencies between stations. They must operate standalone (but of course they’ll need to communicate for this kind of synchronization for seamless operation).

So 1 client = 1 gateway = 1 machine.

4

Just curious, but how do you handle writing from multiple gateways at the same time to the same source?

5

Seems to me that the common point is the PLC. Add logic for it to manage acks itself, and disable acks in Ignition. Provide one-shot triggers that Ignition can set to acknowledge alarms.

6

Well, that’s another issue… as far as I can tell, Ignition doesn’t have a good way to handle a remote ack (either accepting a remote ack, or issuing one), at least not without scripting.

I’m not sure what you mean by disable acks in Ignition… I would still need alarming in the HMI since the alarm display controls are dependent on built-in alarming logic/functionality. I guess I could build my own controls that operate from PLC tags instead…?

7

Don’t use Ignition’s acknowledgements at all. Make the PLC track acknowledgement itself. It is the only common point, so that’s the only way to not loose acks.