Ericsson RBS 2106 Hardware Reference Manual page 382

4(6)
2 Function Description
Figure 1 Block diagram
The TMA-CM supplies up to six TMAs with 15 V DC and maximum 500 mA to
each TMA. The power output is a 15-pole d-sub connector on the front of the
TMA-CM. A TMA consumes in general 70 − 200 mA.
The TMAs can be individually switched on and off by commands from the
DXU.
The current and voltage to each TMA is measured, and an alarm is generated
if the values are outside specified values, indicating that a TMA is not working
properly. The alarm is transmitted to the DXU on the IOM bus.
The TMA is always used together with its connection cable and connection
plate for bias injectors. The connection plate contains filtering equipment.
An indicator on the front panel is illuminated for each TMA in operational
mode. Whether an indicator is illuminated depends also on the actual
configuration, see Chapter Radio Configurations, RBS 2106 and RBS 2206.
If the TMA or the feeder cable short-circuites, the TMA-CM limits the current to
500 mA.
EN/LZT 720 0250 R1A
IOM Bus
Indicator
Control
TMA
Support
Measurement
+24V DC
x Fault
Indicators
x Oper.
TMA1
x
x TMA2
x TMA3
TMA4
x
x TMA5
x TMA6
DC/DC
TMA1
Converter
TMA2
TMA3
TMA4
TMA5
TMA6
P008456B