Example 4: Analyzing a Logged Temperature Signal

The following procedure describes how to analyze a logged temperature signal to determine the maximum, minimum, and mean values of the signal. This example uses the project you created in Example 1: Logging a Temperature Signal and modified in Example 2: Logging a Temperature Signal with Start and Stop Conditions and Example 3: Displaying Alarms when a Temperature Signal Meets a Specified Value.

Complete the following steps to analyze the logged temperature signal and determine the maximum, minimum, and mean values of the signal.

1. Open the project you saved in Example 3: Displaying Alarms when a Temperature Signal Meets a Specified Value.
2. In the work areas pull-down menu that appears above the Project View, select Playback to switch to a Playback work area. The Playback work area is similar to the Monitor/Record work area in which you logged the signal except that the Data View tab appears with a time bar and various buttons you can use to navigate a logged signal. You also can use logged signals as step inputs in a Playback work area.
3. In the Logged Data window, right-click the last log you created and select Make Active Log from the shortcut menu. The name of the active log appears in bold.
4. Drag the log from the Logged Data window to the Data View tab.
5. Click the Run button to play back the log. You also can drag the slider in the time bar to navigate the log, or you can use the buttons and the pull-down menu on the time bar to adjust how LabVIEW SignalExpress plays back the logged signal. For example, you can adjust the playback speed.
6. Select Add Step»Analysis»Time-Domain Measurements»Statistics to add the Statistics step to the Project View. The Step Setup tab for the Statistics step appears, and LabVIEW SignalExpress selects the logged signal as the step input signal automatically.
7. On the Configuration And Results page of the Step Setup tab, place checkmarks in the Max, Min, and Mean checkboxes to specify that the step returns the maximum, minimum, and mean values of the temperature signal as outputs.
8. Drag the new step outputs to the Data View tab and click the Run button to run the project and display the maximum, minimum, and mean values of the temperature signal on the Data View tab.
9. Select File»Save Project to save the project.