iBT21
Using the
3
P8
Replacing & Installing Clock Backup Batteries
The iBT21 uses 2 AA batteries (included) for backup to provide continuous alarm operation and clock
settings in the event of a power failure. If the backup batteries have been installed and a power failure
occurs or the AC adaptor is accidentally disconnected, the display backlight will not remain lit, but current
time and alarm time settings will be temporarily maintained. Otherwise, you must reset the time and alarm
settings.
Note: You should replace backup batteries when the Battery Low Indicator appears on the display.
1. Please make sure the AC adaptor is connected. Otherwise all settings may be lost during battery
replacement.
2. Open backup battery compartment door located on the bottom
of the unit.
3. Insert two “AA” batteries, checking the + and – ends of the
batteries match the diagram inside the compartment. We
recommend to use alkaline battery for longer life. Do not mix
alkaline, standard (carbon-zinc) or rechargeable (nickel-cadmium)
batteries.
4. Close the compartment cover.
Note: Make sure you dispose of batteries properly (see your local
regulations).
Battery Low Indicator
The Battery Low Indicator is located at the top left of the display.
When it blinks it is time to replace backup batteries.
