Add:9F, Dongguan Building, Jiangnan Ave 4288, Binjiang District, Hangzhou
1 Grounding requirements
Grounding points are not allowed to multiplex. Multi-system master devices share a ground bar. The indoor distribution system uses joint grounding. The grounding resistance of the grounding network should be less than 5 ohms. For areas where the annual thunderstorm is less than 20 days, the grounding resistance of the grounding network can be less than 10 ohms.
2 Grounding of the Main Equipment
The host unit equipment must be grounded, with a cross-section area of 16 mm2 and a ground resistance of less than 10 ohms.
For a common ground bar of a multi-system master device, the cross-sectional area of the earth wire connected from the ground bar to the ground of the building is 25 mm2. For the special area for anti-theft, grounding can be welded.
3 Feeder Grounding
1) The outdoor feeder must be grounded. Each feeder uses a grounding member and a grounding conductor with a cross-sectional area of 16 mm2. The grounding resistance is less than 10 ohms.
2) When the antenna is installed on the tower, it is required to be grounded at 1.5 meters before the feeder is bent; if the length of the feeder to the machine room is greater than 20 meters from this grounding point, it should be connected to the feeder in front of the equipment room once again.
3) There is no tower on the machine room. When the antenna is fixed on the support bar, the feeder must be grounded before being turned from the floor to the room.
4) The feeder's grounding wire is required to be grounded in the downward direction of the feeder, and it is not allowed to run upwards.
5) In order to reduce the inductance of the ground wire of the feeder, it is required that the bending angle of the ground wire is greater than 90 degrees and the radius of curvature is greater than 130 mm.
6) The grounding point of each feeder must not be multiplexed; the grounding point must be in good contact and must not be loosened, and be treated for rust prevention.
7) The number and location of the feeder grounding points should meet the requirements of the design documents.
4 Outdoor Donor Antenna and Antenna Support Grounding
1) Outdoor facilities such as outdoor donor antennas, antenna support rods, and outdoor cabling ladders are required to be grounded and require a grounding resistance of less than 10 ohms.
2) For multiple systems, the outdoor donor antenna and the antenna support ground must be connected to the common ground bar with a 16 square millimeter ground wire, respectively, and the ground wire thickness from the ground bar to the building ground net must be 25 mm2 and the welding is good. Do a good job of anti-rust treatment, outdoor donor antenna and antenna support separately grounded, not allowed to series ground.
5 Lightning rods
Lightning rods require good electrical performance and good grounding. The lightning rod should have enough height to protect the repeater signal source on the tower or on the pole and do anti-rust treatment. The lightning rod must be connected to the ground network.
The outdoor antenna must be within the 45 degree protection angle of the lightning rod.
6 Other grounding requirements
The ground points of the host protection ground, feeders, and antenna support should be separated. Each grounding point requires good contact, no loosening, and anti-oxidation treatment (add anti-rust paint, silver powder, butter, etc.).
All the grounding wires should be fixed with wire codes or tie straps. The appearance should be straight and beautiful.