Briana,
Look under "Alarm Setup", "Severities" for the check box to select the internal bell. If you have a sound card, you may use sounds other than the computer "beep",. as explained in the Help files.
Annunciation
Internal Bell
Check this box to have your computer’s internal bell sound when an alarm is triggered. The computer’s internal beep will sound If you don’t have a sound card installed in your computer, and you haven’t set up the Exclamation event in the Windows Control Panel under Sound. If you want to configure the Exclamation event, use a short sound because when an alarm occurs, the sound is repeated about once per second until the alarm is acknowledged or silenced.
External Bell
Check this box and type a tag name or click the browse button to choose a tag name, to have an external bell sound when an alarm is triggered. An external bell is a sound produced by a horn or some other audio device. The tag name you enter is the tag that is linked to the audio device. It must refer to a bit in the programmable controller.
When an alarm occurs, this bit is set and logic in the programmable controller turns on the bell. When the alarm is acknowledged or silenced, the bit in the programmable controller is reset, and logic in the programmable controller turns the bell off.