Original General Order
95
Section
V
Detailed Construction Requirements for Supply Lines
(Class H, L
and T Circuits)
56.4 Clearance
The basic minimum clearance of guys above the ground and from other wires or cables are specified in Tables 1 and 2. Modifications of these basic clearances are specified in Rules 37 and 38 and by the following provisions.
A. Above Ground
(1) Across or Along Public Thoroughfares: Guys over or across public thoroughfares in urban districts shall have a clearance of not less than 18 feet above ground (Table 1, Case 3, Column A) except that a clearance of not less than 16 feet is permitted for the portions of guys over that part of the public thoroughfare which is an entrance to or exit from industrial or commercial premises; and not less than 14 feet in cases where private residential premises are involved.
Overhead guys along public thoroughfare may have clearances, above ground which is not normally accessible to vehicles, less than as specified in Table 1, Column A, Cases 3 and 4 (18 feet and 15 feet respectively) but sections of such guys between insulators shall have a clearance of not less than 8 feet above the ground, and sections of guys between insulators and poles shall have a clearance of not less than 7 feet above ground, and such guys without insulators shall be not less than 7 feet above ground.
(2) Over Private Property: Those portions of guys over private roadways or areas normally accessible to vehicles may have a clearance above ground less than 18 feet (Table 1, Case 3, Column A) but not less than 16 feet in rural districts and not less than 14 feet in urban districts.
B. Above Railways and Trolley Lines
(1) Which Transport Freight Cars: The clearance specified in Table 1, Cases 1, Column A (25 feet) is based upon the maximum height of standard freight cars, 15 feet 1 inch from top of rail to top of running board. This clearance shall in case be reduced more than 5% because of temperature, wind or mechanical loading.
(2) Operated by Overhead Trolley: The clearance of 26 feet specified in Table 1, Case 2, Column A is based upon a trolley pole throw of 26 feet. Guys and span wires may have clearances of less than trolley throw distance (26 feet) above the running surfaces, top of rail or surface of street, used by trolley cars or coaches provided the guys and span wires are not less than 4 feet above the trolley contact conductors and are encased in wood boxing or moulding 7/8-inch or more in thickness for distances of at least 2 feet horizontally from the vertical plane through each trolley contact conductor.
C. From Conductors
(1) Crossing in Spans: Crossing in Spans: Vertical clearances at points of crossing not less than as specified in Table 2, Case 1, and radial clearances not less than as specified in Table 2, Case 18, shall be maintained between guys or span wires and conductors supported on other poles.
(2) On Colinear Lines: The radial clearances between guys on a line and conductors on a collinear line shall be not less than as specified in Table 2, Case 18. Vertical clearances not less than as specified in Table 2, Case 1, shall also be maintained at points of crossing between guys on a line and conductors supported on other poles of a colinear line.
(3) Parallel on Same Poles: The radial clearances between guys and conductors which are approximately parallel and supported by the same poles shall be not less than as specified in Table 2, Case 18.
(4) Passing on Same Poles: The radial clearances between guy and conductors of different ownership shall do so only between pole pin positions or outside of the outer pin position on the crossarm.
a) Overhead Guys: Overhead guys passing through the level of conductors of different ownership shall do so only between pole pin positions or outside of the outer pin position on the crossarm.
b) Anchor Guys: Undergrounded portions of anchor guys which pass through the level of communication conductors at positions other than between pole pin positions or outside of the outer pin position shall be sectionalized by insulators neither less than 6 inches nor more than 18 inches above the level of the communication conductors (see App. G, Fig 49b) and the guys shall clear such conductors by not less than 3 inches (Table 2, Case 19, Column C).
D. From Guys or Span Wires
(1) Crossing in Spans: Vertical clearances at points of crossing not less than 18 inches as specified in Table 2, Case 1, Column A and radial clearances of not less than 12 inches shall be maintained between guys or span wires and other guys or span wires which are not attached to the same poles.
(2) Passing and attached to Same Pole: The radial clearance between different guys, different span wires, or different guys and span wires, attached to the same pole shall not be less than 3 inches.
(3) Approximately Parallel and Attached to Same Pole:
a) Overhead guys or Span Wires: Where two or more overhead guys or two or more spans wires are approximately parallel and attached to the same poles, either or both of which poles support supply conductors, such guys or spans wires shall have a vertical separation of at least 1 foot between the points of attachment on the pole, or poles, which support the supply conductors. In cases where such separation is not practicable, other means to insure the effectiveness of the guy or span wire insulators shall be employed but in no case shall the distance between any guy or span wire be less than 3-inches, measured perpendicularly at the insulator. This rule shall not prohibit the contact to the same shims and shall not apply to guys or span wires acting in different directions, nor to guys or span wires in which insulators are not required.
b) Anchor Guys: Where two or more guys attached to a pole supporting supply conductors are attached to the same grounded anchor, either directly or through the medium of a stub, they shall be separated at the pole by a vertical distance of at least 1 foot, provided any guy wire shall not be less than 3 inches from the surface of the insulator in any other guy. In lieu of securing this 3 inch minimum separation by means of the 1 foot minimum separation of guy attachments at the pole, it shall be afforded by separation of attachments at the pole, it shall be afforded by separation of the grounded anchors or by other practicable means which shall insure the minimum clearance of 3 inches. The provisions of this rule do not apply to guys which act in different directions from the pole or to guys attached to grounded metal structures or to guys which do not require insulators.
E. From Poles
Where passing guys are less than 15 inches from surface of pole and less than 8 feet below supply conductors of less than 20,000 volts supported on the same pole, such guys shall be sectionalized, in addition to the normal sectionalization required by Rule 56.6, by means of insulators in accordance with Rule 56.6-A as though attached to the pole or structure.
F. From Transformer Cases
All portions of guys 6 inches or more from the surface of poles or crossarms at the guy attachments shall not less than 4 inches from transformer cases and hangers. Portions of guys within 6 inches of the surface of poles or crossarms to which they are attached shall not be less than 1 ½ inches from transformer cases and hangers.
G. Above Buildings
The minimum vertical clearance of 8 feet specified for guys above buildings (Table 1, Case 6 Column A) may be reduced over roofs of 3/8 pitch (37 degrees from the horizontal) or greater to a clearance of not less than 2 feet.