SU10 - GO95 -Rule 57.4-F

Messengers, and metal sheathed cables, which are bonded and grounded as specified in Rule 57.8 shall have clearances not less than the minimum clearances required for conductors of 0-750 volts with all of the following provisions being applicable:

Such grounded messengers and cables may be attached to the surfaces of poles or wood crossarms at less than the clearances specified in Table 1, Column D, Cases 8 and 9. When attached to pole or wood crossarm at less than 15 inches from center line of pole such grounded messenger or cable shall be not less than 4 feet vertically above or 6 feet vertically below any unprotected supply conductor except that where a guard arm (or arms) is placed above messenger and cable as specified in Rule 57.7, the clearance of 6 feet may be reduced to not less than 4 feet below unprotected conductors of 0-750 volts (see App. G, Fig. 53).

Such grounded messenger and cable when supported on the same crossarm with unprotected conductors in excess of 750 volts shall be placed on the side of pole opposite the unprotected conductors (see App. G, Fig. 54)

Such grounded messenger and cable when supported on the same arm with unprotected conductors of 0-750 volts, shall be placed at not less than pin spacings (Table 2, Case 15, Column D) beyond the outermost unprotected conductor on the same side of pole (see App. G, Fig. 54).

The clearances required in this Rule 57.4-F between a cable and unprotected conductors shall not be held to apply between a grounded cable (and its messenger) and protected conductors of the same circuit on poles where unprotected enter (or leave) a cable. On such poles no grounded section of messenger or cable shall be less than 15 inches from surface pole.

Where two or more cables are attached to the surface of the same wood pole in accordance with the provisions of this Rule 57.4-F, they shall be placed on the same side of pole when their vertical separation is less than 8 feet but in case shall the vertically separation be less than 1 foot.

(1) Attached to Surfaces of Poles and Crossarms: Such grounded messengers and cables may be attached to the surfaces of poles or ~~wood~~ crossarms at less than the clearances specified in Table 1, Column D, Cases 8 and 9. When attached to pole or ~~wood~~ crossarm at less than 15 inches from center line of pole such grounded messenger or cable shall ~~be not~~ not be less than 4 feet vertically above or 6 feet vertically below any unprotected supply conductor except that where a guard arm (or arms) is placed above messenger and cable as specified in Rule 57.7, the clearance of 6 feet may be reduced to not less than 4 feet below unprotected conductors of 0-750 volts ~~(see App. G, Fig. 53)~~ (see Fig 57-1 A).

(2) Supported on Same Crossarm above 750 Volts: Such grounded messenger and cable when supported on the same crossarm with unprotected conductors in excess of 750 volts shall be placed on the side of pole opposite the unprotected conductors ~~(see App. G, Fig. 54)~~ (see Fig 57-1 B).

(3) Supported on Same Crossarm 0 - 750 Volts: Such grounded messenger and cable when supported on the same arm crossarm with unprotected conductors of 0-750 volts, shall be placed at not less than pin spacings (Table 2, Case 15, Column D) beyond the outermost unprotected conductor on the same side of pole ~~(see App. G, Fig. 54)~~ (see Fig 57-1 C).

(4) Between Cable and Unprotected Conductors: The clearances ~~required in~~ ~~this Rule 57.4-F~~ between a cable and unprotected conductors shall not be held to apply between a grounded cable (and its messenger) and protected conductors of the same circuit on poles where unprotected enter (or leave) a cable. On such poles no grounded section of messenger or cable shall be less than 15 inches from surface pole.

(5) Two or More Cables Attached to the Surface of Pole: Where two or more cables are attached to the surface of the same wood pole ~~in accordance with the provisions of this Rule 57.4-F,~~ they shall be placed on the same side of pole when their vertical separation is less than 8 feet but in case shall the vertically separation be less than 1 foot.

(1) Attached to Surfaces of Poles and Crossarms: Such grounded messengers and cables may be attached to the surfaces of poles or crossarms at less than the clearances specified in Table 1, Column D, Cases 8 and 9. When attached to pole or wood crossarm at less than 15 inches from center line of pole such grounded messenger or cable shall not be less than 4 feet vertically above or 6 feet vertically below any unprotected supply conductor except that where a guard arm (or arms) is placed above messenger and cable as specified in Rule 57.7, the clearance of 6 feet may be reduced to not less than 4 feet below unprotected conductors of 0-750 volts (see Fig 57-1 A).

(3) Supported on Same Crossarm 0 - 750 Volts: Such grounded messenger and cable when supported on the same crossarm with unprotected conductors of 0-750 volts, shall be placed at not less than pin spacings (Table 2, Case 15, Column D) beyond the outermost unprotected conductor on the same side of pole (see Fig 57-1 C).

(4) Between Cable and Unprotected Conductors: The clearances between a cable and unprotected conductors shall not be held to apply between a grounded cable (and its messenger) and protected conductors of the same circuit on poles where unprotected enter (or leave) a cable. On such poles no grounded section of messenger or cable shall be less than 15 inches from surface pole.

(5) Two or More Cables Attached to the Surface of Pole: Where two or more cables are attached to the surface of the same wood pole they shall be placed on the same side of pole when their vertical separation is less than 8 feet but in case shall the vertically separation be less than 1 foot.