General Order 95
Section V
Detailed Construction Requirements for Supply Lines
(Class H, L and T Circuits)
56.7 Location of Sectionalizing Insulators
A. Overhead Guys
Insulators installed in overhead guys to sectionalize such
guys as required by any portion of Rule 56.6
shall be located at a distance of not less than 6 feet and not more than
9 feet, measured along the guys, from the points of attachment of the guys
to poles, crossarms or structures (see Figures
56–5
, 56–6
and 56–7
).
In such overhead guys which are less than 17 feet in
length with no section grounded, insulation at one location, approximately
equidistant from each support will be sufficient.
Overhead guys attached to wood poles, crossarms or
structures and to grounded anchor guys or metal poles shall be sectionalized
at not less than one location, 6 to 9 feet (measured along the guys) from
the attachment at the wood pole, crossarm or structure (see
Figure 56–5
and Figure56–6
).
Branched guys (bridle guys) which are attached
at two or more positions to the same crossarm or pole line structure, and
which are required under the provisions of Rule 56.6 to be sectionalized,
shall be sectionalized by means of insulators in the main guy and all branches
except one, so that no two branches of such a guy constitute a continuous
metallic path between separate points of attachment to crossarms or structures
(see Figure 56–7
). In conforming with these requirements, insulators in branches of guys
should be placed as far as practicable from attachments at pole or crossarm
but not more than 9 feet therefrom.
All insulators in overhead guys shall be
8 feet or more vertically above the ground.
Note: Revised January 21,
1992, by Resolution SU–10.
B. Anchor Guys
An insulator shall be installed in
each anchor guy which is required to be sectionalized by Rule
56.6–A
or 56.6–B
, so that such insulator is located:
(1)
8 Feet or more above the ground;
and
(2) 8 Feet or more below the level of the lowest supply conductor, or 6
feet or more from surface of pole and one foot or more below the level of
the lowest supply conductor (see
Figure 56–8
).
These sectionalizing requirements
for anchor guys can normally be met by insulation at one location; however,
short guys or other conditions may require insulation at two locations:
a) One location being 8 feet or more above the ground; and
b) The other location either 8 feet or more below the lowest supply conductor,
or 6 feet or more horizontally from surface of pole and one foot or more below
the level of the lowest supply conductor.
In order
to prevent trees, buildings, messengers, metal–sheathed cables or other
similar objects from grounding portions of guys above guy insulators, it
is suggested that anchor guys be sectionalized, where practicable, near
the highest level permitted by this Rule.
Ungrounded
portions of anchor guys which pass through a level of communication conductors
at positions other than between the pole and pole pin positions or outside
of the outer pin position shall be sectionalized by insulators placed between
6 and 18 inches above the level of the communication conductors (see
Figure 56–8B
).
Any anchor guy which enters the ground less than 8 feet below the lowest
level of supply conductors on the pole or structure shall be treated as
an overhead guy which is grounded by means of a grounded anchor guy or metal
pole.
A grounded horizontal brace of a “sidewalk” guy shall in no case be less
than 8 feet below the level of the lowest unprotected supply conductor on
the same pole (see
Figure 56–10B
).
Note: Revised January 21, 1992, by Resolution SU–10.
C. Truss Guys
An insulator shall be installed in each truss guy which is required to
be sectionalized by Rule 56.6–A
, so that such insulator is located 8 feet or more above the ground and
8 feet or more below the level of the lowest supply conductor passing within
8 feet of the guy (see
Figure 56–10
). These requirements can normally be met by insulation at one position;
however, in certain unusual conditions the two 8–foot distances may overlap,
in which case insulation will be necessary at two positions.