Design of Lightning Protection Grounding System in Network Computer Room   1. Lightning protection design The lightning protection grounding system is an important subsystem for the protection of weak current precision equipment and equipment rooms, which mainly ensures the high reliability of the equipment and prevents the harm of lightning. The network center computer room is a place with very high equipment value. Once a lightning strike occurs, it will cause incalculable economic losses and social impacts. According to the relevant provisions of the IEC61024-1-1 standard, the lightning protection level of the central computer room should be set as two Class standard design.     At present, the main power distribution room of the building provides the first-level lightning protection according to the building lightning protection design specification. device). The surge protector adopts an independent module and should have a failure alarm indication. When a module is struck by lightning and fails, the module can be replaced alone without replacing the entire surge protector.   The main parameters and indicators of the secondary and tertiary composite lightning arrester: single-phase flow: ≥40KA (8/20μs), response time: ≤25ns   2. Grounding system design The computer network room should have the following four grounds: the DC ground of the computer system, the AC working ground, the AC protection ground and the lightning protection ground.   The resistance of each grounding system is as follows: 1. The DC grounding resistance of computer system equipment is not more than 1Ω. 2. The grounding resistance of the AC protective ground should not be greater than 4Ω; 3. The grounding resistance of the lightning protection ground should not be greater than 10Ω; 4. The grounding resistance of the AC working place should not be greater than 4Ω;   The lightning protection and grounding system of the network equipment room also includes:   1. Equipotential connection in the equipment room A ring-shaped grounding busbar is set up in the network equipment room. The equipment and chassis in the equipment room are connected to the grounding busbar in the form of S-type equipotential connection, and are laid under the raised floor support with 50*0.5 copper-platinum strips. 1200*1200 grid, laying 30*3 (40*4) copper tapes around the equipment room. The copper tapes are equipped with special grounding terminals. All metal materials in the equipment room are grounded with braided soft copper wires and connected to the building. protected ground. All grounding wires (including equipment, surge protectors, wire troughs, etc.) and metal wire troughs in the project should be short, flat and straight, and the grounding resistance should be less than or equal to 1 ohm.   2. Computer room shielding design The shielding of the entire equipment room is hexahedral shielding with color steel plates. The shielding plate is welded seamlessly before, and the shielding body of the wall is grounded at no less than 2 places with the grounding busbar on each side.   3. Design of grounding device in computer room Due to the high grounding resistance requirements of the network room, an artificial grounding device was added near the building, and 15 galvanized angle steels were driven into the ground grid slot, welded with flat steel, and backfilled with a resistance reducing agent. The static grounding of the equipment room is introduced through a 50mm² multi-strand copper core wire.

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Post time: Jul-22-2022