OPC UA Server Update Rate

What is the tag update rate on the OPC UA Server?
Does it depend on the Driver (e.g. Allen Bradley Driver)?

For a SQL bridge transaction group, what is the limit on the update rate? It seems like I can make it as fast as I wan to.

There is no fixed update rate, it depends on what the client requests.

When Ignition is the client it uses the rate of the scan class / tag group as the sampling interval for items belonging to the subscription.

There’s a lower limit to sampling intervals that depends what version of Ignition you are using but there is no limit on how fast a read or polled-mode scan class, tag group, or transaction group can attempt to read.

Thanks, Kevin.

I’m using Ignition V 8.0.14, do you know the sampling interval for this version?
Presumably if you attempted to read faster than this in a transaction group, it would just read as fast as it could?

Ignition 8+ doesn’t have a minimum sampling interval, it will let you create monitored items with as fast a sampling interval as you’d like to try.

Yeah, that’s pretty much how it works both in and out of subscription groups.

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