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Communication tower lightning grounding requirements

1. Communication tower lightning protection requirements

(1) the mobile communication tower should have perfect direct lightning protection and secondary induction lightning protection devices, and the tower body can be directly used as a conductor. The lightning belt at the tower foot can be reliably connected to the ground network.

(2) solar tower lamps should be used in mobile communication towers. For the aviation sign light with ac power supply, the power line shall adopt the cable with metal outer sheath, and the metal outer sheath of the cable shall be nearby grounded at the top of the tower and the outside of the entrance to the machine room. Lightning arresters shall be installed at the entrance of the machine room for each phase line of tower lamp control line and power line, and the zero line shall be directly grounded.

(3) the mobile communication antenna shall be within the protection range of the flash connector.

2. Communication tower grounding network requirements

(1) the ground network of the communication tower shall extend to a range of 1.5m away from the four feet of the tower tower. The grid size shall not be larger than 3mX3m. The surrounding area shall be enclosed.

(2) if the grounding resistance value of the local network fails to meet the requirements, the area of the ground network can be expanded, that is, 1 ring or 2 ring ring grounding devices can be added at the periphery of the ground network. The ring earthing device is composed of a horizontal earthing body and a vertical earthing body. The periphery of the horizontal earthing body is enclosed. The horizontal earthing body and the ground network should be on the same horizontal plane. The extension grounding body can also be set at the four corners of the tower. The length of the extension grounding body should be limited within 10m to 30m.

Requirements for grounding body of communication tower

(1) the grounding body shall be made of hot-dip galvanized steel. The specifications are as follows:

Steel pipe diameter of 50mm, wall thickness should not be less than 3.5mm

Angle steel shall not be less than 50mmX50mmX5mm

Flat steel shall not be less than 40mmX4mm

(2) the length of the vertical grounding body shall be 1.5m to 2.5m, and the spacing of the vertical grounding body shall be 1.5 to 2 times of its own length. If the soil resistivity is not uniform, can be appropriately lengthened. When it is difficult to bury the vertical grounding body, multiple annular horizontal grounding bodies can be set at intervals of 1m to 1.5m, and shall be connected to each other by welding every 3m to 5m.

(3) twice the width of the side, and 10 times the diameter of the round steel.

(4) the distance between the upper end of the grounding body and the ground shall not be less than 0.7m. In cold areas, the grounding body shall be buried below the permafrost.

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