OPC quick client subscription time inaccurate (wrong)

Hello All!

I am currently testing Ignistion software to find out if it fits our needs. So far the software is pretty straight forward and does what it is intended to do.

I do however run into 1 issue.

I am connecting to a PLC TAG using a OPC-UA gateway. This tag when subscribed to in UAexpert updates at my set update interval of 100ms.

However, when I subscribe to a TAG in the Ignition gateway dashboard, it does not update according to my 100ms minimum interval time. For some reason it always increments in time units of 1000ms.

So the PLC and my gateway are fast enough as displayed in UAexpert. But my Ignition gateway dashboard and Ignition designer do not follow suit.

Thnk you kindly for any input.


There’s a couple reasons for what you’re seeing.

Rest assured, if you subscribe at 100ms then you will get data changes every 100ms as long as the server is actually publishing them that fast.

In the web Quick Client the actual table only refreshes every 1 second, regardless of the speed of the subscription.

In the Designer and Vision Clients you’re bound by the Client Poll Rate project property: https://docs.inductiveautomation.com/display/DOC80/Project+Properties

By default this is 250ms. This doesn’t mean data doesn’t arrive at the gateway any faster, just that the designer or client doesn’t poll the gateway for changes any faster. You can change this to 100ms or faster and then you should see your 100ms updates if they’re actually changing every 100ms. This does increase the load each client or designer places on the gateway though.

(and I think there was a bug in 8.0.x that caused this to be ignored and it was only fixed recently, so you may need to be on the latest nightly release to see it in action)

I never got to thank you,

So, thanks for your answer!

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