Installation Instructions

Outdoor Grounding Guidelines Summary
DEC 2000
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SCt300 BTS Hardware Installation, ATP and FRU Procedures
PRELIMINARY
General
This is a summary of the outdoor grounding guidelines. Outdoor
installations should be based on this summary and site specific
documentation. Motorola publication 68P81150E62 should also be
followed to ground an antenna tower.
This guideline assumes that auxiliary equipment is co–located at the
installation site. All of the equipment referenced may not be present at
every site.
Because outdoor MicroCell/PicoCell installations will involve a variety
of methods, this information is not meant to represent actual physical
layout. It is meant to act as an aid to understanding an effective ground
system.
Chassis Isolation
Regardless of the type of installation (wall, frame, pole), the grounding
plan must have a single point ground to prevent surge/transient currents
from passing through the BTS and auxiliary equipment. The BTS
includes insulation hardware to insure that the chassis will be grounded
by the intended ground path and not through the mounting structure
(frame, pole, or wall).
Master Ground Plate
The Master Ground Plate (MGP) is the key to the outdoor grounding
scheme. The MGP is the single grounding point for all BTS input and
output and provides a uniform ground potential through out the site.
Although the MGP may be implemented differently at each installation,
it must be a plate that is big enough to attach to all the lightning arrestors
and have a ground stud.
The MGP ground stud is the only connection to earth ground for the
BTS hardware.
Main AC Power
The AC power input is single–phase and connects to the BTS by a three
conductor cable. The cable is insulated and connects to the BTS on one
end and the AC source on the other end. The AC power source should
be ground referenced to the MGP at a point closest to the access point.
The line and neutral conductors must be protected by lightning arrestors.
The lightning arrestors connect to the MGP at the same point as the AC
ground reference.
If an external circuit breaker or an uninterruptible power supply are used,
install them between the AC power lightning arrestor and the BTS.
Antenna
Coaxial cables are used to connect to the antenna(s). The ground
conductor (shield) of the coaxial cable must be ground referenced to the
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