How to Execute a Limited Number of Scans (GS 7.4)

You can specify that the PLC execute your program for a limited number of scans (from 1 scan to 65,535 scans). By selecting the number of scans for the PLC to run, you can monitor the program as it changes the process variables.

On the first scan, the value of SM0.1 is one (ON).

Executing a Single Scan:

1.The PLC must be in STOP mode. If it is not already in STOP mode, switch the PLC to STOP mode.

2.Choose Debug>First Scan from the menu bar.

Executing Multiple Scans:

1.The PLC must be in STOP mode. If it is not already in STOP mode, switch the PLC to STOP mode.

2.To execute multiple scans, choose Debug>Multiple Scans from the menu bar.

The Execute Scans dialog box appears.

3.Enter a value for the desired number of scans, and click "OK" to confirm your choice and dismiss the dialog box.

Note:

Be sure to change the PLC back to RUN mode (click the Run button in the toolbar or choose PLC>RUN) when you are ready to resume normal program operation.

See Also:

Overview of Debugging and Monitoring Features (GS 7.1)

How to Display Status in the Editor Windows (GS 7.2)

How to Display Status in a Status Chart (GS 7.3)

How to Download a Program (GS 6.3)

Timestamp Mismatch Error (ensuring that project in programming device matches project in PLC)

Cross Reference and Element Usage (ensuring that program edits do not cause duplicate assignments)

Program Edit in RUN Mode

PLC RUN/ STOP Mode

Writing and Forcing Outputs in STOP Mode