Reference Manual

Table Of Contents
Product Data
It is possible to supply external transmission equipment from the battery
cabinet. The transmission equipment is provided with power supply
longer than the RBS.
In event of mains failure, the batteries in the BBS 2000 will deliver the
necessary power to the radio cabinet as well as to the transmission
equipment, if used. This enables the radio system to operate during
mains failure.
The battery back-up can be delivered for 1, 2, 4, 6 or 8 hours back-up
time, depending on the chosen conguration of the RBS.
The BBS can feed +24 V DC or -48 V DC to the TM equipment. The
-48 V DC supply requires an internal DC/DC converter in the BBS.
It is possible to share battery back-up between RBS 2202 and
RBS 2206.
5.6.1 Converting BBS 2202
If BBS 2202 is used, a conversion kit is needed to run RBS 2206. The
battery fuse unit determines which conversion kit should be used:
BFU-21: product number BMY 201 237/5
BFU-22: product number BMY 201 237/6
5.6.2 Weights
Table 54 BBS 2000 unit weight
Unit Weight in kg Weight in lb.
Battery stand, without
batteries
170 375
Battery stand, with 2 batteries
490 1080
Battery stand, with 3 batteries
650 1433
5.6.3 Output Voltage
The voltage range to the RBS cabinet is +20.2 - 29.0 V DC.
Predened voltage +27.2 V DC
Battery low voltage limit +21.0 V DC
5.6.4 BBS Cabinet Hardware
Battery Fuse Unit
The battery fuse unit (BFU) monitors and controls the batteries. It will
cut off the load (the RBS) when any of the following conditions occur:
A mains failure lasts longer than the back-up time. When the
battery voltage drops below a preset value, the BFU disconnects
the RBS. This is to prevent damaging the batteries by over-
discharging. The BFU continues to feed the transmission
EN/LZT 720 0008 R1A
2001-06-26
97 (421)
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