User's Manual

Item Requirements
Equipotential
connection
l Properly ground the devices and auxiliary devices in the room such as
mobile base station, transmission, switching equipment, power supply
equipment, and cable distribution frame. Connect all PGND cables to
the collective protective ground bar. Connect all PGND cables in one
equipment room to one protective ground bar.
l Apply joint grounding to the working ground and protective ground
of devices, which means the two share one grounding network.
l The cable tray, rack or shell, metal ventilation pipe, metal door or
window of the equipment should be grounded for protection.
General
requirements for
grounding
l Do not connect the neutral line of the AC power cable with the
protective ground of any telecom equipment in the equipment room.
l Do not install a fuse or switch on the ground cable.
l All ground cables should be as short as possible, and arranged in a
straight line.
Grounding
resistance
l The grounding resistance must be lower than 1 ohm.
l 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.
l Measure the grounding resistance periodically to ensure effective
grounding.
Routing of signal
cable
l Do not arrange the signal cables overhead in the equipment room. All
signal cables must be led into the site underground.
l Use the cables with a metal jacket or place them into a metal pipe if
they come out/in the equipment room.
l Ground the idle lines inside the cable in the equipment room.
l Signal cables should be deployed on internal walls. Do not deploy
outdoor aerial cables.
l Keep signal cables away from power cables and surge protection
devices.
Collective
ground cable
l Use a ground ring or ground bar for the collective ground cable.
l Do not use aluminum cables as ground cables. Adopt measures to
prevent electrification corrosion when connecting different metal
parts together.
l Use a copper busbar as the collective ground cable with a cross-
sectional area of no less than 120 mm
2
(0.19 in.
2
), or use the galvanized
flat steel of the same resistance. Insulate the collective ground cable
from the reinforcing steel bars of the building.
Grounding lead-
in
The grounding lead-in should be a maximum of 30 m (98.42 ft) long. Use
the galvanized flat steel with cross-sectional area of 40 mm x 4 mm (1.58
in. x 0.158 in.) or 50 mm x 5 mm (1.97 in. x 0.197 in.).
AP3x10xN&5x10xN&5x30xN&6x10xN&7x10xN
Hardware Installation and Maintenance Guide 5 Appendix
Issue 12 (2015-08-05) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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