Audit Companion Alarm Reference Alarm times are entered in 24 hour format. AC also allows you to use the plus and minus keys to increment and decrement the time which allows a user to set "relative alarms" in macros. There are two ways to use alarms. For a standard alarm you enter a message and a time. At your selected time AC will beep and display this message. If you start quiet mode after entering an alarm time, AC will exit after the alarm.