METABOLISMO EN LOS TCA

1. The clearance specified in Table 7-1 item E-3 and E-5 may be reduced when the sign is grounded but shall not less than 0.15 meters for span wires, guys and messengers, communication cables and services drops and not less than 0.3 for open wire conductors.

79 B. Item E-4 and E-6

1. The clearance specified in Table 7-1 item E-4 and E-6 may be reduced if adequate separation is provided by means of a suitable non-conducting separator but shall be not less than 7.5 cm. for span wires, guys and messengers, communication cables and shall service drops.

7.5 CLIMBING SPACE

7.5.1 The climbing space shall be provided on one side or quadrant of all poles or structures supporting communications conductors excepting at the level of one pair of conductors attached to the pole below the lowest cross-arm and the top 0.9 meter of poles carrying communication conductors only which are attached directly to the pole.

7.5.2 The climbing space shall be maintained in the same position on the pole for minimum vertical distance of 1.2 meters above and below each conductor level through which it passes, excepting that where a cable is attached to a cross-arm or a pole with the cable less than 0.2 and 0.4 meters from the center line of the pole supporting conductors on line arms.

7.5.3 The position of the climbing space shall not be shifted more than 90 degrees around the pole within a vertical distance less than of less than 2.4 meters.

7.5.4 Vertical conductors, when in a suitable protective covering attached directly to the surface of the pole, terminal boxes or similar devices which do not extend more than 14 cm. from the surface of the pole, and guys, will not be held to obstruct the climbing space provided not more than one guy and one other of the above named obstruction are installed in any 1.2 meter vertical section of the climbing space.

7.5.5 Cross-arms and their supporting members are allowed in climbing spaces provided that, where buck arms are involved, any arms within in climbing spaces are treated as double arms.

7.5.6A guard arm, a longitudinal run of messenger, cable or insulated wire will not be held to obstruct the climbing space where because the presence of a building wall or similar obstacle will not permit the cable to be placed on the side of the pole opposite the climbing space.

7.5.7 Pole steps shall be suitably placed for the purpose of facilitating climbing past the level of terminal boxes, cable, drop wires, and guard arm.

7.6 VERTICAL RUNS, RISERS, GROUND WIRES

7.6.1 Vertical runs of communication wires or cables supported on the surface of wood poles or structure shall be covered by a suitable protective covering within a vertical distance of 0.9 meters above 1.8 meters below unprotected supply conductors supported on the same pole or structure. Vertical runs of communication wires or cables on surface of a wood pole shall be covered by a suitable protective covering within 1.8 meters radius of any other pole supporting supply conductors except that those portion of such runs which are more than 0.9 meters above or 1.8 meters below the level of unprotected supply and conductors need not be covered. The protective covering shall be rigid polyvinyl chloride plastic pipe with a minimum wall thickness of 6 mm. or equivalent. Cables and drop wire runs to or from terminal boxes are exempted from these requirements for covering under the following conditions.

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a) Where guard arms are installed above messengers or longitudinal cables which are less than 1.8 meters below but not less than 1.2 meters below unprotected supply conductors of 750 volts, or where cables are supported on cross-arms at not less than 35 cm. from center line of pole, in which case any portion of metal sheathed cable runs on the surface of the pole below the guard and in the same quadrant as the longitudinal cable, or below and on the same side of the poles with a cross-arm which supports a longitudinal cable.

b) Runs of briddled conductors attached to the surface of the pole, need not to be covered provided such runs are below the guard arm and in the same quadrant as the longitudinal cable, or where such runs are below on the same side of the pole with a cable arm and are not in the climbing space. When briddled runs are not required to be covered, they shall be supported by briddle hooks or rings spaced at intervals of not more than 0.6 meters.

Runs which terminate in the top enclosure which afford ample mechanical protection the runs, may extend within 2.4 meters of the ground without being treated as risers.

Vertical runs shall be treated as risers where within a distance of 2.4 meters from the ground.

7.6.2 Risers

Risers of wires or underground cables shall be encased in securely grounded metal or plastic pipe from the ground line to a level not less than 8 feet above the ground line.

Risers shall be covered by a suitable protective covering as defined in Rule 7.6.1 where within a additional strength shall be provided by the use of guys or other suitable construction.

7.7.2 Where guys are used with poles or similar structures capable of considerable deflection before failure, the guys shall be able to support the entire stress, the pole below the point of guy attachment acting merely as a strut.

7.7.3 Guys shall be attached to structures as nearly as practicable at the center of load. They shall be maintained taut and such strength as to meet the safety factors of Rule 4.3.2 under the loading condition of Rule 4.2.

7.7.4 Guy wires shall be protected by the use of guy thimbles or their equivalent when attached to anchor rods or though bolts.

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7.7.5 Soft wood poles, around which any guy having an ultimate strength of 2,300 kg. or more is wrapped, shall be protected by suitable guy shims. Hooks, lag screws or other equivalent means shall be used where necessary to prevent the guy from slipping along the pole.

7.7.6 The general requirements governing the sectionalizing of guys by means of insulators are based upon the exposure or proximity of the group to supply conductors. The following requirements shall apply to the treatment and sectionalizing of guys.

A. Guys attached to or passing poles or structures supporting only communication conductors need