Question on "On Change" mode historization

Ignition
,
1

I have a question about historization in On Change mode.

When I have this mode set, the previous value is historized to the database and the current value waits in the queue until the change occurs again. What is the reason for this behavior and is it possible to configure it in such a way that if the value changes, the current value and its timestamp will be stored immediately?

Below is an example where the value is saved when changing but it is equal to the previous value the current value is different and is not saved.

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image1581×743 83.1 KB

Best regards
Michał

2

This is documented behavior of Deadband Style == "Analog", which is what you get for "Auto" when a tag's data type is float or double.

Set your tag's Deadband Style to "Discrete".

1 Like
3

What's happening is that Ignition is holding onto the current value until a value comes in that's outside the deadband. When that happens it stores that temporary value and then puts the new value in the temporary store.

1 Like
4

Thank you, now I understand this two modes. My day saved!