Figure 4-2 Disconnecting Cables; Figure 4-3 Removing The Heua - Huawei BBU3900 Hardware Maintenance Manual

BBU3900
Hardware Maintenance Guide
Take proper ESD protection measures, for example, wear an ESD wrist strap or a pair of ESD
gloves, to prevent electrostatic damage to the boards, modules, or electronic components.
Step 2 Set the MCB labeled SW7 on the DCDU-03B to OFF to power off the HEUA.
Step 3 Record all the cable connections on the panel of the board to be replaced.
Step 4 Disconnect the power cable and monitoring cable from the HUEA, as shown in

Figure 4-2 Disconnecting cables

Step 5 Unscrew the cover plate, and then unscrew the HEUA, as shown in

Figure 4-3 Removing the HEUA

Step 6 Install the new board, tighten the screws on the board until the tightening torque reaches 0.55
N·m, and then reconnect the cables.
Step 7 Take off the ESD wrist strap or gloves, and then pack up all the tools.
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Postrequisite
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Issue 03 (2010-06-05)
CAUTION
Place the replaced component into the ESD box or bag. Then, place the ESD box or bag
into a carton padded with foam or into the packing box of the new component.
Fill in the fault form with the details of the replaced component.
Contact the local Huawei office to handle the faulty component.
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
4 Replacing the Components in the OMB
Figure 4-3.
Figure 4-2.
4-3