Lucent Technologies MERLIN LEGEND Release 5.0 Installation Manual page 62

MERLIN LEGEND Communications System Release 5.0
Installation 555-650-140
Installing the Control Unit
AC Power and Grounding
!
!
WARNING:
An improper ground can cause equipment failures, service
outages, and electrical shock. Verify that the AC power uses an
approved ground for its primary ground, that all voltage-limiting
devices are grounded to an approved ground, and that the ground
is one of the approved grounds listed below.
Approved Grounds
Approved grounds are listed below, in order of preference:
Building Steel. The most preferred ground.
Acceptable Water Pipe. Must be a metal, not plastic or vinyl,
underground water pipe at least
contact with the earth for at least 10 ft. (3 m).
It must be electrically continuous so that the protector ground is
uninterrupted. (Check for insulated joints, plastic pipe, and plastic water
meters that might interrupt electrical continuity.)
A metallic underground water pipe must be supplemented by the metal
frame of the building, a concrete-encased ground, or a ground ring. If
these grounds are not available, the water pipe ground can be
supplemented by one of the following types of grounds:
— Other local metal underground systems or structures, such as
— Rod and pipe electrodes, a 5/8-in. (1.58-cm) solid rod or ¼-in.
— Plate electrode, a minimum of 2 square ft. (61 square cm) of
tanks and piping systems, but not gas pipes
(0.63-cm) conduit or pipe electrode driven to a minimum depth of
8 ft. (244 cm)
metallic surface exposed to the exterior soil
½
in. (1.27 cm) in diameter, and in direct
Issue 1
June 1997
Page 2-13