Please follow the steps below and change the mentioned file.
1. Shut down the application.
2. Navigate into <Supportcenter>/conf directory.
3. Open the file web.xml in an editor.
4. Search for the following line :
PS: 360 timeout (in minutes)
Change 360 into 20 or 30 or according to your requirement.
5. Save the file and close.
6. Start the application.
Now any Support reps who is idle for more than the mentioned time, then he will be logged out automatically.