Reference Manual

Self Test and Supervision
Preconditions and Initiation
Initiates automatically at application software start.
Description
All BTS have inbuilt fans, which may run at four different speeds full,
middle, low and stop. The main task of the fans is to circulate the air in
the BTS and replace old, warm air with new, cooler air. The RBS 2102
and 2101 has a climate system with a control unit that controls the
temperature and the humidity of the RBS. The control unit is divided
into three units:
ECU The ECU supervises the climate unit,
handles the alarms and controls the FCU.
CCU The CCU controls the climate unit
independently, but in case of abnormal
function the ECU can disconnect the
climate unit and override the CCU,
(emergency stop).
FCU The FCU is a speed control of the
magazine fans and a distributor of their
alarms.
The climate unit consists of among other things a heater, temperature-
and humidity sensors, a compressor and a condenser. The compressor
will start at an initial temperature of 32

C and will stop when the
temperature falls to 25

C. If the enclosure temperature falls below 10

C,
the heating unit will be switched on and it will be switched off when
the temperature rises above 15

C.
The cabinet heating up time to > 0

C depends on the ambient
temperature and the time the cabinet has been shut down. However, the
heating up time shall not exceed 2 hours under any circumstances.
40.4.11 Power Conditions
Purpose
Supervises the units used for energy control and the power level of the
AC and DC power.
Preconditions and Initiation
Initiates automatically at activation of the application software.
Description
Supervises the units used for energy control. Detects faults in those
units for example power supplies, internal or external batteries, fans,
cooler, heater or climate sensors. Supervises the power level for AC
power and DC power. AC mains failure is detected.
312 (421)
EN/LZT 720 0008 R1A
2001-06-26
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