Ericsson RBS 2106 Hardware Reference Manual page 277

1 Product Overview
The BFU-22 supplies battery back-up system voltage to the RBS and
disconnects the battery when it has reached its lower discharge limit. The
contactor can disconnect and connect the battery with a control signal from
the Supervision Module (SM).
1.1 Main Functions
The BFU can supply priority power to transmission equipment. Power to
transmission equipment can be distributed even if a battery is not present. The
relay can select the power source with a control signal from the SM.
The BFU communicates on the EPC bus (opto cable) with the DXU. If the
EPC bus is not present, the BFU operates at its default values. The battery
voltage, current and temperature are monitored and alarms are sent on the
EPC bus.
The BFU disconnects the battery, if the current is too low or the temperature is
too high. When the temperature returns to normal, the battery is reconnected.
If the battery temperature sensor is faulty, a "Battery temperature sensor fault"
message is sent to the DXU.
Battery back-up can also be manually disconnected or disconnected by
control signals on the EPC bus.
The SM provides self-detection of internal faults and stores them in non-
volatile memory.
2 Dimensions
Table 1
Height
267 mm
Size and weight
Width
82 mm
Depth Weight
226 mm 5 kg
3(6)
EN/LZT 720 0276 R1A