Next, the editor of graphite grounding will introduce the issues and requirements in the lightning protection grounding construction plan. Let's take a look together:

Lightning protection grounding is divided into two concepts: one is lightning protection, which prevents damage caused by lightning strikes; The second is electrostatic grounding to prevent the harm caused by static electricity. 1、 Factory lightning protection is divided into overall structural lightning protection, which is the lightning protection of the main factory building. The main foundation is laid with grounding electrodes and grounding strips to form a grounding network with a grounding resistance of less than 10 ohms. Connect with the main body of the steel bars or steel structures in the main factory building. The cement concrete roof should be connected to lightning protection strips or lightning rods, and there should be grounding test points on the ground outside the wall. The steel structure should be directly led to the roof using galvanized flat iron.

2、 The grounding of the power supply system is divided into protective grounding and working point grounding. Protective grounding is the grounding of the shell of live equipment. The grounding of the working point refers to the grounding of the neutral line. The grounding method is the same as the lightning protection grounding method, and the grounding resistance is less than 4 ohms. If the requirements cannot be met, a grounding electrode should be added. If the conditions are poor, electrolyte should be added and/or soil should be replaced. The working grounding and protective grounding are independently led out from the distribution room, and the system can be combined into one. The working mode, such as separating the ground wire and neutral wire, can also be combined into one and led to the electrical system (or equipment). The grounding system must be repeatedly grounded.

Common problems in lightning protection and grounding construction:

1、 The length of the lightning protection strip, down conductor, grounding body, and voltage equalizing ring overlap is insufficient, and there are slag inclusions, weld beads, and air holes at the welding points.

2、 Miswelding or missing welding of the connection points of the ground steel mesh, as well as the omission of external grounding connection points or embedded parts for detection points.

3、 When using structural steel instead of lightning rods (nets) and their down conductors, the anti rust paint on the galvanized layer was damaged, the bolt connection pieces were not treated, and there were gaps between the pieces.

4、 The spacing between the grounding points is too large, no compensator is installed at the deformation joint where the grounding wire crosses, the installation depth of the grounding body is insufficient, or the lead wire has not been treated with anti-corrosion.

5、 The metal objects on the roof (such as pipes, ladders, flagpoles, and equipment enclosures) are not connected to the roof lightning protection system, and the equipotential bonding grounding wire diameter is insufficient.

6、 The branch line of electrical equipment grounding (neutral) is not connected to the grounding main line.

Requirements for lightning protection and grounding construction:

1. The material meets the specifications and design requirements, the connection is reliable, the anti-corrosion measures are in place, and the grounding system is smooth and complete.

2. Specification for using building foundation steel bars as grounding bodies and down conductors, with complete documentation; The installation of lightning protection belts and grounding wires should be straight, aesthetically pleasing, and firmly fixed; The grounding of the roof and exposed metal components is complete; The metal casing of the equipment and the grounding of the equipment foundation are not missing.

3. The grounding point identification is clear, and the lightning protection grounding test points are complete.

The above is the sharing of the editor of graphite grounding, hoping to be helpful to everyone! If you want to learn more about related information, please continue to follow this website. New news will be pushed to everyone every day!