Huawei BTS3900 V200R010 Site Maintenance Manual page 25

5 Replacing Components of the BTS3900
The DCDU-01, installed under the BBU, supplies DC power for the cabinet and has the function
of surge protection. Replacing the DCDU-01 disrupts the services carried on the corresponding
cabinet. It takes about 20 minutes to replace the DCDU-01.
5.8 Replacing the FAN Unit
The FAN unit works with the air inlet box in the cabinet to form a ventilation path. The FAN
unit provides forced ventilation and dissipation for the BBU and RFU. Replacing the FAN unit
may result in over-temperature alarms due to interruption of heat dissipation for the cabinet but
has no negative effect on services of the BTS. It takes about 20 minutes to replace a FAN unit.
5.9 Replacing the PMU
When the PMU is faulty and cannot be repaired in time, you must replace it.
5.10 Replacing a PSU
When a PSU is faulty and cannot be repaired in time, you must replace it.
5.11 Replacing a WRFU Module
This describes how to replace WRFU. The WRFU is located on the top of the BTS3900 cabinet.
The WRFU provides the following functions: modulation and demodulation of baseband or RF
signals, data processing, and signal combination and division. The replacement of the WRFU
disrupts the services carried on it. It takes about 10 minutes to replace a RFU module.
5.12 Replacing the Power Supply Subrack of the BTS3900
The power supply subrack is located in the lower cabinet of the BTS3900. It can be installed
with the PSU and PMU to provide the power input and output ports. It takes about 25 minutes
to replace the power supply subrack.
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BTS3900 WCDMA
Site Maintenance Guide
Issue 07 (2009-08-30)