Requirements for Safe Use of Wires and Cables

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With the rapid development of the communications industry in recent years, cable products have also developed at an astonishing speed. The use of cables has also been greatly improved and is flexible. The cable can be coiled on the cable reel with a bending radius ≥20D, and D is the outer diameter of the cable. The fire-fighting cable is smokeless and non-toxic when burned, and the insulating material is inorganic material "non-combustible". It will not produce harmful gases during combustion, and will not cause secondary pollution. It is called an environmentally friendly green product. The safety is good.

In addition to the normal power supply, the fire-fighting cable can start the fire-extinguishing equipment in the flame to reduce fire losses. At the same time, it is particularly reliable for personal safety. The copper sheath is a good conductor and the best grounding wire, and it continues to the full length of the cable, which greatly improves the sensitivity and reliability of grounding protection. And it has a long service life, inorganic insulating materials, high temperature resistance, not easy to age, and its service life is many times longer than that of organic insulated cables? Under normal working conditions, its life span can be equivalent to that of a building.

Safety Requirements:

1. When the cables cross each other, the high-voltage cable should be under the low-voltage cable. When one of the cables passes through the pipeline protection or is separated by a partition within 1 meter before and after the cross, the minimum allowable distance is 0.25 meters.

2. When the cable approaches or intersects the hot pipe, the minimum distance between parallel and cross is 0.5m and 0.25m respectively.

3. When the cable crosses the railway or road, it should be protected by pipeline, and the pipeline should extend more than 2 meters from the track or road.

4. The distance between the cable and the building foundation should ensure that the cable is buried outside the loose water of the building. When the cable enters the building, it should be protected by a pipe, and the protective pipe should also exceed the loose water of the building.

5. The grounding distance between directly buried cables and grounding devices should be 0.25-0.5 meters, and the buried depth of directly buried cables should not be less than 0.7 meters, and should be buried under permafrost.

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