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 TM 5-684/NAVFAC MO-200/AFJMAN 32-1082
LOCATION STAKE
LINE OF GUY
8 In BY
In
by
SLOPE
DISTANCE
K
0.5
.
.
.
.
.
1
Figure 4-20. Log anchor
a. Guy clamps. Use three-bolt guy clamps which
provide the necessary attachment to pole eyebolts,
are made of steel with steel or malleable riders. All
guy insulators, or ground rod thimbles. This method
should not be used as a substitute for guy clamps or
parts are galvanized to prevent rusting. The num-
ber of clamps used depends upon the breaking
grips.
strength of the guy strand as shown in table 4-5. A
4-52. Guy strain insulators.
two-bolt clamp is not recommended for use because
The NESC requires that ungrounded guys attached
of its limited strength. Little maintenance of the
to supporting structures carrying open-supply con-
bolts will be required, if guy clamps are properly
ductors of more than 300 volts, or guys that are
installed and the bolts are retightened after the
exposed to such conductors, be insulated. Other-
load is applied. A loose guy can easily be tightened
by repulling and clamping. The clamping surfaces
wise, the guys must be effectively grounded. In guys
that are effectively grounded, adequate electrical
should be free of oil or grease, but need not be
cleaned to the extent necessary for electrical con-
clearances and safe working space for the lineman
may be maintained by installing insulators, if this
nectors. The end of the wire extending beyond the
clamp is covered on the end with a guy clip or
is the facility's policy. A guy insulator installation
must have a rated dry flashover voltage at least
several wraps of wire.
b. Preformed grips. A preformed grip consists of a
double, and a rated wet flashover voltage at least as
high as, the nominal line voltage between conduc-
number of wires of suitable material and size, which
are prefabricated to loop through a thimble or insu-
tors of the guyed circuit. A guy insulator installation
lator and to wrap around the guy strand. The more
may consist of one or more individual guy strain
the load is increased, the tighter the grip is drawn.
insulators. Linemen should be trained to recognize
Grips can be applied without tools and can be
a grounded guy. When work is to be done on a
retensioned up to three times within 3 months after
grounded guy assembly, electrical continuity will
installation. Otherwise, they should not be consid-
need to be maintained and such guys should be
ered salvageable for reuse. Due to the length of
treated as being an ungrounded device. Install
preformed grips, it may be necessary to use clamps
proper protective equipment on adjacent grounded
where space is limited.
guys while the lineman is working on or near ener-
c. Serves. Instead of clamping, a method called
gized conductors. Ungrounded guys are insulated
with porcelain, wood, fiberglass, or other materials
serving may be used. This utilizes the guy strand
end (on small-size or low-strength guy strands) to
of suitable mechanical and electrical properties.
4-27
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