Instruction manual
POWER AND GROUNDING
Approved floor grounds are those grounds on a floor of a high-rise building suitable for connec-
tion to the ground terminal in the riser closet and to the PBX equipment single point ground termi-
nal. Such grounds may be one of the following:
Building steel
The grounding conductor for the secondary side of the power transformer feeding the
floor
Metallic water pipes
Power feed metallic conduit supplying panel boards on the floor
A grounding point specifically provided in the building for the purpose
Lightning Protection
A coupled bonding conductor is tie-wrapped to all trunks. The coupled bonding conductor can be
any one of the following:
10-AWG ground wire
Continuous cable sheath
Six unused pairs of wire
The coupled bonding conductor connects the cabinet single-point ground block and runs all the
way to the approved ground located nearest the telephone company-owned protector block at the
building entrance facility.
When an auxiliary cabinet is provided with a multi-carrier cabinet system, a 6-AWG ground wire
connects the system cabinet single-point ground block to the auxiliary cabinet ground block. It is
recommended that the ground wire be routed as close as possible to the cables connecting the
system cabinet and the auxiliary cabinet.
If auxiliary equipment is not mounted in the auxiliary cabinet, then the power supply for this
equipment must be plugged into one of the two convenience outlets located on the back of the
multi-carrier cabinet to preserve ground integrity. The convenience outlet is fused at 5 amps.
The dedicated Manager I or G3r-MT terminal should be plugged into the other convenience
outlet.
Sneak Current Protection
Sneak fuses protect the building wiring and circuit packs from ‘‘foreign potential’’ by providing a
current interruption capability. Sneak fuse panels, when provided, are installed on the switch side
of the network interface. All incoming and outgoing trunks and off-premises station lines pass
through the sneak fuses. Sneak current protection is required for installations in Canada. The
sneak fuses must be CSA certified.
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