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:
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.
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.