General Order 95
Detailed Construction Requirements for Supply Lines
(Class H, L and T Circuits)
54.11 Insulators in Vertical and Horizontal Position Without the Use of
Wood Crossarms, More than 750 Volts (Vertical and Triangular Construction)
Insulators supporting conductors of more than 750 volts may be attached to poles in vertical or horizontal position, and where so attached, the following rules shall apply:
An insulator mounted directly on the side of a pole shall be considered as in a horizontal position;
An insulator mounted directly at the top of the pole in a vertical position shall be considered as in a vertical position.
B. Pole Arrangement and Clearances
(1) Clearances: Conductors and the hardware used to secure the conductor to the insulator shall have clearances from the centerline of the pole (as specified in Rule 54.4–D2 ) when supported on insulators that are mounted in horizontal position. Conductors and the hardware used to secure the conductor to the insulator shall have clearance from the surface of the pole as specified in Table 1, Case 9, Columns E and F when mounted in a vertical position.
(2) Conductor Arrangement: Not more than one circuit over 750 volts
shall be attached to any pole in triangular configuration. Not more than
four conductors of any one circuit over 750 volts shall be attached to a pole.
The number of circuits attached to a pole, except in triangular configuration,
is not restricted (a circuit is in triangular configuration only when it
consists of one phase on insulators mounted vertically at the top of the
pole and other phases on insulators mounted horizontally on opposite sides
of the pole).
Conductors over 750 volts shall not be attached to more than three sides (there being four sides) of any pole at the same level of any circuit group. Climbing space in conjunction with these attachments shall be maintained as specified by Rule 54.11–F .
All conductors of the same circuit in the same vertical plane shall be of the same material.
The vertical separation between conductors of the same circuit supported in the same vertical plane shall be not less than spacing as indicated in Table 2, Case 20, Columns E, F, G, H and I.
Vertical Clearances between Conductor Levels
The vertical clearance of not less than that specified in Table 2, Cases 8 through 13, shall be maintained between the lowest conductor of a circuit group and the conductors supported on the same pole of the next lower circuit group.
(1) Where Insulators are in Vertical or Horizontal Position (Vertical or Triangular Configuration) More than 750 Volts: Climbing space shall be maintained through the levels of conductors for a vertical distance of not less than 4 feet above the top conductor and not less than 4 feet below the lowest conductor.
EXCEPTION: For a circuit
at the top of the pole, the climbing space shall be maintained to the lowest
conductor of the circuit on the climbing side of the pole. For a pole top
circuit that includes buck position conductors located within a vertical
distance of 4 feet or less from the lowest associated line conductor, climbing
space need only be maintained to the lowest conductor in the buck position
on the climbing side of the pole.
The climbing space shall be a square of horizontal dimensions tabulated below, and one side of the climbing space shall pass through the center line of the pole (see Figure 54–10 ). Where conductors are deadended (e.g., line and buck or corner construction) below pole top in triangular configuration, 750 - 46,000 volts, climbing space can be located in a quadrant of the pole. When quadrant climbing space is used, the dimensions of the square shall be 42 inches.
Voltage of Conductors
Dimensions of Square (Inches)
750 - 46,000 Volts
46,000 - 75,000 Volts
More than 75,000 Volts
48 plus 1/2” per kV in Excess of 75 kV
(2) Dimensions of Climbing Space Where Conductors are Deadended
in Vertical Configuration: Climbing space through conductors shall be
a square of the horizontal dimensions tabulated below, and shall be located
either on one side or a quadrant of the pole (See
). For a circuit at the top of the pole, refer to the exception in
Note: Revised January 6, 1968 by Decision No. 73453 and May 22, 1990 by Resolution No. SU–5 and October 9, 1996 by Resolution SU–40.
Voltage of Conductors
Dimensions of Square (Inches)
750 - 7,500 Volts
7,500 - 46,000 Volts
More than 46,000 Volts
36 plus 1/2” per kV in Excess of 46 kV
G. Allowable Climbing Space Obstructions
Allowable climbing space obstructions in triangular and vertical configuration without the use of wood crossarms are:
(1) Crossarms, brackets, and their supporting members.
(2) Insulators which support line conductors, jumpers, and incidental wires may
extend one–half of their diameter into the climbing space.
(3) Conductors may extend one–half of their diameter into the climbing
(4) Suitably protected (covered only by wood, see
a) Vertical risers; or
b) Vertical runs; or
c) Ground wires
Such risers, runs, and grounds are allowable, provided that not more than
one is installed in any 4–foot section of climbing space.
(5) Guys (except those guys which are metallically contacting metal pins
or deadend hardware as specified in Rule
). However, not more than two guys having a vertical separation of 18 inches
or less can be installed in any 4–foot section of climbing space.
(6) Street light brackets may extend one–half their diameter into climbing
space. Associated street light bracket struts are allowed in climbing space.
(7) Operating rods (e.g., switch rods) and their associated hardware may
extend one–half their diameter into climbing space.
(8) Bands, limited to 6 inches in width with no more than one band allowed
in any 24–inch section of climbing space (these limitations are excluded
for pole stubbing and pole splicing bands when pole step provisions are installed.)
(9) Bolts and their washers. If bolts are bonded, a secure electrical
contact shall be made. The covering of bolts and bond wire is not required
in triangular and vertical configuration without the use of wood crossarms.
Modification of these requirements in Rule 54.11–G are specified in: Rule 54.7–A3 for wood crossarm construction; Rule 54.9–F for rack construction; Rule 54.10–F3 for multiconductor cable with bare neutral construction; Rule 54.12–F3 for extended rack construction; and Rule 58.3–A3 for switches.
Note: Rule 54.11 added January 6, 1968 by Decision No. 73455 and revised July 22, 1968 by Decision No. 74342, March 9, 1988 by Resolution E–3076, May 22, 1990 by Resolution No. SU–5 and October 9, 1996 by Resolution SU–40.