The Active Valve (AV) Operation Change Data dialog box is accessed by clicking on the Active Valve Operation button in Attribute Browser when you have a valve selected. This dialog box allows you to specify the curve that describes the valve's stem position with respect to time. This screen is not available until an Active Valve has been created with the Active Valve Data. Note that the different types of active valves will have different opening characteristics for similar stem positions.

Stem Change Curve

A change in the ratio of the stem position for a valve will produce a transient (a ratio of 100 means the valve is fully open, 50 indicates the stem has turned 50% of fully closed and 0 implies the valve is fully closed). Select the Stem Change Curve from the pull-down menu or use the Browse  button to open the Curve Editor to create a new curve or edit an existing curve. Create a Stem Change Curve where: X = Time of simulation and Y = Percent open (100 = 100% wide open and 0 = 0% fully closed).

Purge - Remove the current valve operation curve.

Create/Update - Save any changes and close the Operation Change dialog box.

Cancel - Discard any changes and close the Operation Change dialog box.