TigerWeb automatically logs you out after 30 minutes of inactivity. While you are working in eLearn, TigerWeb doesn't know you are still "active" and may time you out.
After you log into eLearn through TigerWeb, go back to the TigerWeb browser window or tab and close it. This will keep TigerWeb from logging you out of eLearn.
Be sure to do this if you will be taking a test or exam in eLearn.