Huawei AP4030DN Hardware Installation And Maintenance Manual page 76

Huawei AP4030DN
Hardware Installation and Maintenance Guide
Item
equipped with a
surge arrester
Grounding of
DC power
distribution
Equipotential
connection
General
requirements for
grounding
Grounding
resistance
Routing of
signal cable
Issue 02 (2015-05-18)
Requirements
For the equipment room in the city, install the power supply arrester

with the nominal discharging current no less than 20 kA. For the
equipment room built in the suburbs subject to lightning strike,
install the power supply arrester with the nominal discharging
current larger than 60 kA. For the equipment room in the mountain
areas easily subject to lightning strike, or in the separate high-rise
buildings in the city, install the power supply arrester with the
nominal discharging current larger than 100 kA.
The ground cable of the surge arrester should be a maximum of 1 m

(3.28 ft) long.
Connect the DC working ground (positive pole of the -48 V DC

power supply or the negative pole of the 24 V DC power supply)
with the indoor collective ground cable nearby. The total ground
cable should meet the maximum load of the equipment.
The power equipment must have the DC working ground cable,

which can connect the power equipment to the collective ground
cable of the telecommunication site (or the protection ground bar of
the equipment room).
Ground the devices and auxiliary devices in the room such as

mobile base station, transmission, switching equipment, power
supply equipment, and cable distribution frame properly. Connect
all PGND cables to the collective protection ground bar. Connect all
PGND cables in one equipment room to one protection ground bar.
Apply joint grounding to the working ground and protection ground

of devices, which means the two share one grounding network.
The cable tray, rack or shell, metal ventilation pipe, metal door or

window of the equipment should be grounded for protection.
Do not connect the neutral line of the AC power cable with the

protection ground of any telecom equipment in the equipment room.
Do not install the fuse or switch on the ground cable.

All ground cables should be as short as possible, and arranged

directly.
The grounding resistance must be lower than 1 ohm.

The upper end of the grounding body should be at least 0.7 m (2.30

ft) over the ground. In cold areas, bury the grounding body below
the frozen ground.
Measure the grounding resistance periodically to ensure effective

grounding.
Do not arrange the signal cables overhead in the equipment room.

All signal cables must be led into the site underground.
Use the cables with metal jacket or place them into the metal pipe if

they come out/in the equipment room.
Ground the idle lines inside the cable in the equipment room.

Signal cables should be deployed on internal walls. Do not deploy

outdoor aerial cables.
Keep signal cables away from power cables and surge protection

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5 Appendix
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