Tag History Sample Rate

Is there a way to change the history sample rate based on a BOOL tag? If our plant is running we want to sample a pressure transmitter at 1sec but when not running only sample at 5 min.

You’re after a ‘driven’ tag group:


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The first question before you start working on this is: do you really need this?

The historian has a deadband. So when the plant isn’t running, if the pressure remains pretty stable, it should remain within a deadband and not register new values.

When the deadband is configured correctly, it works pretty good at storing only the interesting changes.

A driven tag group (as suggested by @BenKearney), is indeed your other option.
I certainly wouldn’t change the historian configuration programatically, since every change like that also produces DB results, and will in some cases even slow down your historical data tables.

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Thanks for that, I am new to ignition so am used to using periodic sample rates.
I think you 100% correct and I don’t need to worry about changing the rate and use the deadband.