General Order 64-A
Detailed Construction Requirements For Supply Lines
(Class H, L and T Circuits)
Open Wire Drops.
Open wire drops from the line conductor to another level on the pole or structure shall not impair the climbing space, nor shall they pass between the conductors of any other circuits other than the pole conductors, nor shall they clear the conductors of other circuits by a distance of less than 12 inches under the most severe conditions. It is recommended that wherever practicable the lead wires from the line conductors to the other level be carried in conduit attached to the pole and properly protected, as specified in Rule 54.6-A1. Where the distance between levels is in excess of 10 feet, additional supports shall be installed equidistant from the levels involved.
B. Low Voltage Racks.
(1) General: Conductors of 0-750 volts which are of the same material throughout and have the equivalent of a double braid weatherproof covering may be attached to one side of pole sin spans not exceeding 250 feet in light loading districts.
(2) Vertical Separation and Span Lengths: A minimum vertical separation of 6 feet shall be maintained between the top conductor supported by the rack and conductors of more than 750 volts carried above it on the pole, or a guard arm shall be installed directly above the rack and parallel to the conductors, in which case the minimum vertical clearance below conductors of more than 750 volts may be reduced to 4 feet. The vertical separation of conductors carried on the rack shall be not less than 4, 8, or 12 inches for spans of 150, 200 and 250 feet, respectively.
(3) Conductor Clearance From Surface of Pole: The conductors shall maintain a clearance of not less than 3 inches from the surface of poles.
Climbing Space: The 15
inch center line of pole clearance specified in Table 1, Case 7, need not
apply, provided that the full climbing space is maintained past the rack for a
distance of 4 feet above and 4 feet below the top and bottom conductors,
respectively, supported thereon.
Lateral runs and service drops may be taken from the main rack run and supported by a rack installed on the side of the pole opposite the main rack. Such lateral runs and service drops shall not be permitted to obstruct the climbing space when installed on the opposite side of the pole from the main rack conductors they shall form an angle of departure of not less than 30° from the main rack conductor, which for the purpose of measuring the angle of departure is considered as being on the same side of the pole as the lateral runs and service drops in question. No limit is placed on the angle between the service drop and the main rack run where such service drop is taken from the main rack. To facilitate the climbing space requirement it is recommended that racks be put on the sidewalk side of pole. (See App. G, Fig. 89.)