eSpace IAD
Troubleshooting
3 Co mmon Troubleshooting Methods
Issue 02 (2012-02-29)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
93
No.
Specifications
group of ground electrodes. If the power supply and devices are in the same
equipment room, try to use the same protection ground bar for them.
4
Add lightning protection circuit for the AC power interface.
5
The positive pole of the -48 V DC power supply (or negative pole of the 24 V
DC power supply) must be grounded at the output of the DC power supply.
6
The working ground and protection ground of the DC power supply must use
the same group of ground electrodes with the protection ground of the
switches. If the power supply and devices are in the same equipment room, try
to use the same protection ground bar for them.
7
Add surge protection for the DC power interface.
Table 3-11
Signal cable ground specifications
No.
Specifications
1
If there are digital trunks that connect a transmission device directly or
indirectly to a wireless communication station, install an E1 lightning
protection device for the relative interface of the transmission device.
2
Equip the cables laid outdoors with the metal jacket whose two ends are well
grounded, or connect the cables to the protection ground bar of the equipment
room. For cables inside equipment room, install the lightning protection device
at the device interfaces. The PGND cable for the lightning protection device
should be as short as possible.
3
Both ends of the external conductor of the coaxial cable and those of the shield
layer of the shielded cable must have good electric contact with the metal shell
of the device they connect to.
4
In the incoming and outgoing signal cables to and from the office, the idle line
pair ins ide the cable must be grounded for protection.
5
The Tone & Data Access (TDA) cable will inevitably pass the Main
Distribution Frame (MDF) with security unit when going out the office. Its
shield layer must be connected to the protection ground of the MDF. The MDF
must use the same group of ground electrodes with the cabinet.
6
The signal cables within the area of the communication office and mobile
station should not be arranged aerially.
Table 3-12
Cable ground specifications
No.
Specifications
1
The ground leading cannot be arranged parallel to the signal cable, and
crossover is not allowed.
2
The ground cable cannot be led in aerially, but buried in the earth globally or