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The underground drop is now usually either spliced directly into the cable or is connected at pedestal
terminals. Occasionally it is run up a pole, and in the past in BC, it has been connected in pull boxes to stubs
using Klick-it, Zebra or preformed closures.
Figure 38: Types of Closures
Installation and Repair technician must always ensure that the Under Ground drops shield is connected at the
NIB and if possible, at the pedestal.
Tii 356
The most common type of station protection is the gas filled fuse less protector. This style replaces legacy
devices that used carbon modules, rods or wafers in their protection circuits. These carbon module arrestor
units are no longer used because they have a tendency to pit or get dusty over time, causing noisy circuits.
Also, once they have been tripped by a high voltage incident they must be replaced.
A fuse less protector must be used if the customer has a power company multi-grounded neutral (MGN) or a
known grounded community metallic cold water supply.
The module is placed between the tip and ring of the drop and the tip and ring of the inside wire. The module
is marked accordingly, and it will provide a path to ground for voltages over the rating occurring from
lightning strikes or power line contact with cable pairs. The ground connection remains open on the tip and
ring until the over voltage condition causes the modules to trip and direct dangerous current to ground.
Figure 39: TII 356
Loading coils
Loading coils are coils that do not provide coupling to any other circuit, but are inserted in a circuit to
increase its inductance.
Page 47 of 130
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