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 TM 5-684/NAVFAC MO-200/AFJMAN 32-1082
work, then a live-line contractor may need to be
and are not intended to substitute for training or
hired on a scheduled and/or a nonscheduled basis.
operating procedures; for meeting specific industry
General energized-line maintenance practices cov-
guidelines; or for meeting federal, state, local, or
-
ered in chapter 4, section VI, serve only as a guide
facility regulations and rules.
Section III - AVOIDING PROBLEMS
1-14. Operating conditions.
1-16. Electrical connections.
Always observe the four cardinal rules of electrical
Connections are an essential part of any electric
maintenance.
circuit. Good electrical contact is essential. Dirt is
a. Keep the equipment clean.
the enemy of good contact. Whenever an electrical
b. Keep the equipment dry or lubricated as ap-
connection is to be made, extreme care must be
taken to ensure all dirt, rust, corrosion, insulation,
propriate to the part.
c. Keep screwed parts tight.
oil, and other contaminants are removed. The con-
tact surfaces should be bright, clean metal. This
requirement applies to connections made by solder-
1-15. Detecting potential trouble.
ing, clamps, twisted sleeves, compression fittings, or
any other method.
Diagnostic devices, where available, allow checking
a. Aluminum. Connections of aluminum items
the system for potential trouble before it occurs.
should always include the application of a joint com-
Potential problems may also be detected by the use
of four of our five senses: see, hear, touch, and smell.
pound which will ensure metallic contact by dissolv-
a. See. Many abnormal conditions can be de-
ing the aluminum oxide which is always present on
tected by visual inspection: some of the patterns
aluminum and aluminum alloy surfaces in air. The
contact surfaces of aluminum conductors and con-
identifiable by sight are cleanliness, distortion,
color, misalignment, size, and position.
nectors should first be vigorously cleaned with a
b. Hear. Changes in the intensity of noise, pitch,
stainless steel wire brush to a bright finish and
or frequency are significant clues to operational
then immediately coated with the aluminum-oxide
inhibiting compound.
changes and possible malfunctions. Some of the
b. Copper. Copper contact surfaces should be
sound patterns that may indicate malfunctioning
are squeaking, rattling, knocking, and whistling.
cleaned, but not connector barrels. The barrels
c. Touch. Among the damaging characteristics
should be cleaned on the inside.
which may be identified by touch are vibration, wet-
c. Dissimilar metals. Only connectors designed
ness, and heat. Caution should be exercised in
for the purpose should be used to connect aluminum
touching components which are normally hot
and copper items.
d. Testing. Accessible connections may be tested
enough to burn personnel on contact or live parts
with hazardous potentials.
using an infrared detector only if the connection is
d. S m e l l . Burning insulation and battery fumes
under load as covered in chapter 3, section I.
provide distinctive odors which signal component
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