Question:
How does a tag’s deadband (PercentDeadband property) work? Does it depend on a configured scale, or is it calculated from each value updated in the tag?
Solution:
If you have tag set up as I/O Min = 0, I/O Max = 1000, and PercentDeadband = 10, the deadband’s value is 100 (10%).
Examples:
- Tag value = 500 and device goes up to 400: the value is updated.
- Tag value = 400 and device goes up to 350: the value is NOT updated, because it has changed only 50.
- Tag value = 400 and device goes up to 300: the value is updated, because it has changed 100 from the tag’s latest value.
Therefore, it will always be 100 (10%), no matter the tag value nor the set up scale. In this case, the update will require a variation of 100 (more/less) from the value in the tag.
