User's Manual
Open Information
DESCRIPTION 9 ( 20 )
EAB/RWB/ZG Christina Wilson 18/1551–HRB 105 102/1 Uen
EAB/RWB/Z (Dennis Radenholt) 2003-06-16 B
Prepared (also subject responsible if other) No
Approved Checked Date Rev Reference
E
4.2 MCPA
The MCPA is a 20 W RF power amplifier with a bandwidth of 20 MHz. The
MCPA can simultaneously amplify, in RBS 3104, up to two RF carriers, by
dividing the power over the carriers.
The MCPA subrack is connected to the RF subrack through front panel cabling.
4.3 XALM
The XALM handles the customer specific alarms as well as alarms for Ericsson
equipment, such as door alarm.
4.4 Capacitor Unit
The Capacitor Unit (CU) receives the -48 V DC supply, which powers the RBS.
The CU ensures that the RBS remains in operation during short transient drop
of power. The CU smooths out irregularities in the supplied power, and the unit
is subdivided into three electrically separated sections.
4.5 Climate System
The climate system comprises the Climate Unit (CLU) in the cabinet door, a
Fan Unit in the cabinet, and a Heater in the cabinet. The CLU comprises the
two External Fans, a Heat Exchanger (H/E) and an Active Cooler (A/C).
At low ambient temperatures, only the H/E operates to cool the cabinet. The
Heater is used during start up at low ambient temperatures to ensure that the
temperature inside the cabinet rises above a certain level. The Heater and A/C
are interlocked to prevent them from operating at the same time.
At high ambient temperatures, the A/C contributes to maintain sufficiently
low cabinet temperatures.
The H/E and A/C co-operate to ensure that long time average power
consumption is minimized.
Climate Unit
The Climate Unit (CLU) is a cooling device that includes a Heat Exchanger, an
Active Cooler, a compressor control unit, and the External Fans. The speed of
the External Fans is temperature controlled.
The H/E consists of a counter-flow H/E with external air circuit fans.
The A/C consists of compressor, reducing valve, condenser and evaporator.
Heater
The Heater is DC supplied and is controlled by a thermostat to avoid
overheating.