Article 458. Plastic for cable joint

The permissible temperature of each cable is shown in the following table.

However, the temperature of butylene injected into the cable should not exceed 130-140 deg C for the connection box with porcelain, andthe connection box and porcelain should bewarmed up to 60 deg C before butylene is injected.

Table 458 Permissible temperature of cable connection box

Article 459. Cable head

The insulated pipe should be molded byinsulated EP rubber (Ethylene Propylene Rubber) or semi-conductive EP rubber with excellent electricalcharacteristics, and bewith an internal semi-conductive layer and an external semi-conductive layer, and hasno harmful defect such as bubbles.

Article 460. Connection, distribution of cable insulated by rubber

The code connection machine, the connection box and other apparatuses should be used at connection between the codes, cabtyre cables, cables or theconnection between these cables.However, when connecting cabtyre cables with a cross sectional area of 8mm2 or more, the connection part should be covered by the insulation with theequivalent or more effect ofan electric insulated wire, and insulated cover should be sulfureted completely. (When a durable metallic defense device is given on connected part, above requirement is not applied.)

Article 461. Cable core insulated by paper

The terminal edge of cable insulated by paper should be tightly wrapped by plastic tape etc. to prevent penetrating water and dust into the cable.

Article 462. Cable core insulated by rubber

Refer to article 461.

Section 8 CABLE INSTALLATION IN EXPLOSIVE ROOM AND EXPLOSIVE OUTDOORS EQUIPMENT

Article 463. General

The explosive room and the explosive outdoor are defined as the room or outdoor whereunpowderg is kept, the flammable gas is filled and a lot of flashover dust exists.

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Article 464. Prohibited places for cable joints setup

The connection box and the branch box should not be installed in the explosive room or nearthe explosive outdoor equipment because the accidents at these boxes occur easily since they are normally assembled at the site.

Article 465. Place that have condenser equipment

The offset distance from cables to explosive equipment such as valves for gas pipelines, condenser for changing explosive gas to liquid, etc. should be secured over 100mm.

The cable cover should not be made of inflammablematerials (jute and butylene) because the fire of the cable might continue and expand in the event of the explosion.

Article 466. Intersection with corrosive chemical pipe

The cable intersecting with the pipeline includes the corrosive chemical substanceshould be inserted in a pipe to prevent corrosion by the substance in the event of leaking the substance.

Article 467. Cable go in floor

When explosive substance might flow into adjacent place through the hole of the cable or the cable block, the hole or the cable block should be filled with a nonflammable material.

Article 468. In explosive room

The cable in the room where gas and hot air with the specific gravityfo0.8 or less exist together as well as its cable canal should be covered with sand. The cable canal should be covered with sand for 1.5m or more from the cable installation point, which is touching the wall of room with the explosion hazard.

Article 469. Protection to prevent erosive

When the cable might be damaged by eroded chemicalsubstance, it should be covered strictly in a nonflammable defense box.

Article 470. Cable joints to electric equipment

When the cable is connected with the electric equipmentor instrument, it should be surely connected with the connection box.

Article 471. Use of cable funnel and dry pit

Cable canal under dry condition or cover to seal slit in dust resistance box in explosive room is permitted to be used to prevent explosion.

It is prohibited that general public access near the room.

Article 472. Cable installation outdoor

When the cable pipe connected with other pipesis at the explosive andoutdoor place, the cable should be inserted into a steel pipe, fixed firmly and installed in the following directions to avoid the damage.

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1.When other pipes are made of a nonflammable material, the pipe is allowed to be constructed at the same side.

2.The cable is installed in the direction to avoid explosion hazard.

In addition, light specific gravity of hot airis defined as the specific gravity of 0.8 or less, and heavy specific gravity of hot air is defined as more than 0.8.

Section 9 PAINTING AND MARKING

Article 473. Painting for cables

A specific painting method should be executed by the following methods or more effective methods.

1.When the cable is constructed indoor under the normal environmental condition: Antirust paint (Oil or bitumen, etc.)

2.When the cable is constructed indoor under the environment condition which aluminum, lead and steel might be corroded : An appropriate paint with the chemical impact resistance

3.When the cable is constructed outdoor : Waterproof and antirust paint (Bitumen, etc.)

4.When the cable connection box and other support structures are constructed in water or underground: Anti-corrosion, waterproof and antirust paint (Bitumen or the high temperature bitumen, etc.)

Article 474. Display of cable information

Display of information of the cable line should be in accordance with to Article112 in Technical Regulation Vol.1.

Article 475. Place of sign

The sign of cable should be made from the following materials.

1.Plastic, aluminum, and painted corrugated iron : Room with air conditioning facilities

2.Plastic, aluminum, and surely painted corrugated iron : Humid room and outdoor

3.Plastic: Room with corrosive substance and underground

Moreover, the figure markof the sign should usually be described by good quality paint, and by casting if it is specially needed.

Article 476. Fixing the sign

The sign of the cable should befirmly fixed by galvanizing wire or steel wire of1 to 2mm in diameter.

However, the steel wire should be painted by antirust material (Bitumen etc.).

Article 477. Sign of cable in the ground

The sign of underground cable and connection box should be tightly rolled by tapeprventto corrosion by underground water, and damage by earth and sand.

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