1, the connection of the grounding trunk line and the grounding body, should be used as far as possible welding welding, the connection should be added to the block, in order to increase the welding area. Installation, the screws must be tightened, it is generally desirable to high-pressure grounding wire with a diameter of 12mm or 16mm screws, and need to be galvanized rust treatment; the contact surface should be kept flat, there can be no gaps. The connection should be placed in a place where it is easy to check and maintain, and if it is buried underground, the position should be marked on the ground. Public distribution transformer grounding trunk and grounding body connection point, generally buried in the ground below 100 ~ 200mm deep.
2, from the grounding body or from the grounding body trunk lead to the grounding line should be laid, not through the pipe laying or buried in the building, but when crossing the floor or wall, it should be protected through the pipe; grounding trunk should be supported firmly, and coated with yellowish-green or black; the use of multi-stranded wires for the grounding line, the connection should be used to connect the lugs (copper connector), can not be directly bending the head of the wire pressure connected to the screws in the place where there is vibration, to add a spring washer. In places where there is vibration, spring washers should be added. Grounding trunk and grounding body connection method 1 a grounding body connection trunk 2 a wire 3 a wiring lug 4 a grounding body 5 a grounding trunk flat steel width of two times.
3, multi-pole grounding or grounding network between each grounding body connection trunk, if you need to provide grounding wire, it is to be installed in the trench, as shown in Figure 1-62. Trench to be covered with a trench cover, the trench cover should be flush with the ground, grounding body connection trunking in the use of wide vertical installation, should be pre-drilled wiring with through holes, and in the connection of pre-tinned, easy to lead to high-voltage grounding wire.
Precautions for the installation of high-voltage grounding wire
I, in the installation of high-voltage grounding wire, the first check the route is no electricity, in the guardianship of the high-voltage grounding wire under the supervision of the person on duty by skilled workers or electricians to manipulate.
Two, the installation of high-voltage grounding wire, must be connected to the grounding end, after connecting the conductor end, and must be well fought, not to be entangled around. Remove the grounding wire, the same. Placement or removal of the grounding wire, should use insulated rod and wear insulated gloves.
Three, the installation of high-voltage grounding line must be two people. If a single person on duty, only allowed to use the grounding knife gate grounding, or the use of insulating rod to close the grounding knife gate.
Four, the same pole erected multi-layer power lines to place high-voltage grounding line, should be hung first low voltage, high pressure; first hung "ground", hung "fire"; first hung grass-roots level, hung after the lower level. Remove the grounding wire, with the same pace. Placement or removal of the grounding wire, should use insulated rod, the human body is not allowed to touch the grounding wire.
Fifth, high-voltage grounding wire cross-section should be suitable for short-circuit current requirements, shall not be less than 25 square millimeters of multi-stranded bare copper soft wire, and the adoption of public wire clamps firmly in the conductor, to stop the use of entangled methods of grounding or short-circuiting around. Grounding line and inspection department should not be connected between the fuse or switch.