Sennheiser BW 900 - Manual (Page 19)

Basic settings
19
Changing the battery during a call
If you have a second, fully charged battery, you can replace a flat battery
even during an office phone call as follows:
Note:
Do not take the battery out of the headset during a Bluetooth device
call as this will interrupt the phone link immediately!
f Take the flat battery out of the headset.
The headset LED
ቧ goes off and the hook LED ´ lights up red indicat-
ing the headset is not received (out of transmission range).
The call is briefly interrupted, however, the call is held by the base sta-
tion for 40 seconds.
f
Take the fully charged battery out of the spare battery charging
slot
¶
and insert it into the headset.
The headset LED
ቧ
flashes blue three times indicating the headset is
switched on. Subsequently the headset LED
ቧ
flashes blue once every
5 seconds to indicate that the headset is in standby mode and a ring
tone is heard via the headset.
f
Press the headset hook button
ብ
.
The call is resumed.
f
Insert the flat battery into the spare battery charging slot
¶
.
The spare battery charging LED
¿
lights up red to indicate that the
battery is being recharged.
¿
¶
´
ቧ
ብ