the ring side of the line toward the central office and touch-the other test set lead alternately to the faulty
leads. A click will be heard as each lead is touched. If the pair were short-circuited only, these clicks
would not be heard.
(2) As a rule, where both sides of a line are grounded, the faults are adjacent. Because this is
not always the case, test to determine the portion of the circuit in which each fault exists. When the
general location has been established, locate each fault individually.
(a) When an open wire lead is grounded, locate the fault by inspection, if possible. If the
fault cannot be located by inspection, open the line at one or more points and test to locate the ground
definitely.
(b) When a drop wire is grounded, locate the fault by observation, if possible. If the fault
cannot be located by observation, open the drop wire lead at one or more points and test to localize the
fault. When the fault has been located, remove the cause of the fault and make necessary repairs. If the
cause of the fault cannot be removed, relocate the line adjacent to that point. When the damage to the
drop wire is great, replace the damaged part with new wire.
(c) When a protector is grounded, determine whether cleaning the carbon blocks or
replacing them is the better maintenance job. If the blocks are to be cleaned, be careful not to increase
the air gap between the blocks.
(d) An inside wire can become grounded in many ways. Insufficient insulation when the
wire is crossing a grounded object, excessive moisture, interference as a result of repairs or changes to
the premises, or improper installation at the telephone set or protector are some causes of a grounded
inside wire. When the trouble has been located, determine whether the wire should be repaired or
replaced.
e. Clearing grounds.
(1) The exact location of a ground on the drop, block, open, inside, or bridle wiring may be
determined by visual examination. Where visual examination is impracticable or difficult, rerun the line
and reinforce the insulation at points of contact with possible ground leads.
(2) A ground in the substation protector may be cleared by cleaning or by replacing the
carbon blocks.
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