Use the fields in the Error Handling section of the Calculation tab to specify what should happen if ClearSCADA detects an anomalous condition when it evaluates the calculation expression. Example anomalous conditions could be: a divide by zero condition or a type mismatch condition.
- Action—Specify the action that ClearSCADA should take if it detects an anomalous condition when it evaluates the calculation expression. Select a combo box option from the following:
- Don't Update—Select this option if ClearSCADA should not update the Calculation Point.
- Update Quality Only—Select this option if ClearSCADA should only update the quality of the Calculation Point. ClearSCADA will set the quality to Sub-Normal.
- Update with Last Value—Select this option if you want ClearSCADA to update the Calculation Point with the current value. ClearSCADA will set the quality of the Calculation Point to Sub-Normal, and the timestamp to the time that ClearSCADA executed the calculation expression.
- Update with Defined Value—Select this option if you want ClearSCADA to update the Calculation Point with a Value that you define (see below). ClearSCADA will set the quality of the Calculation Point to Sub-Normal, and the timestamp to the time that ClearSCADA executed the calculation expression.
NOTE: This option is not available on Time Calculation points.
- Value—Use this field if you selected the Update with Defined Value combo box option. Specify the value with which ClearSCADA should update the point if an abnormal condition occurs when it evaluates the expression.