Keep LabVIEW Front Panel Displaying Continuously When Running TestStand

When using a LabVIEW Action Step in TestStand, you may expect the VI’s front panel to open and remain visible while the test runs. However, a front panel will typically close (or the VI will complete execution) as soon as TestStand finishes calling the VI—unless the VI is configured and executed asynchronously.

If your goal is to keep a VI’s front panel open beyond the execution of a LabVIEW Action Step, ensure that the VI is not run synchronously. Instead, configure the step to run the VI asynchronously, allowing the front panel to remain open until the asynchronous VI itself stops.

Why the Front Panel Closes

By default, TestStand calls LabVIEW VIs synchronously, meaning TestStand waits for the VI to finish running before continuing. After the execution completes, LabVIEW closes the VI, which causes the front panel to close unless the VI is configured otherwise in LabVIEW.

If you want the front panel to:

• Open when the step starts, and
• Remain open until the overall test sequence or workflow is complete,

then the VI must be executed asynchronously.

Run the VI Asynchronously

To keep a front panel open (or allow a VI to continue running after the step completes), configure your LabVIEW Action Step to launch the VI asynchronously. This separates the VI’s runtime from the TestStand step’s lifetime so that TestStand does not automatically close the VI when the step ends.

NI provides guidance on this workflow in the articles below:

• Launching a LabVIEW VI Asynchronously from TestStand
• Asynchronously Starting and Stopping a VI in TestStand

These KB articles cover recommended patterns for asynchronous invocation, safe shutdown, and proper API usage.