Delta logging records the difference between consecutive time-stamped values instead of recording the actual running total.
You can configure rollover properties on a history extension so that rollover occurs when a running total reaches a defined
maximum number and then resets to zero or another defined number.
Prerequisites: The station History space contains existing histories.
- Double-click the point extension and expand the History Config slot.
- In the
MinRollover slot, click on the Null value check box and then enter the desired minimum value.
- In the
MaxRollover slot, click on the Null value check box and then enter the desired maximum value.
- Click Save.
For example, if you are logging energy consumption with the Max Rollover Value property set to 999,999 and the Min Rollover Value set to 100, when the station detects a rollover, the delta logging bases its delta calculation on a maximum value of 999,999 and a subsequent
initial value of 100.