Country-wise HS code tariff relief

List of the table of contents of this article:

• 1,Country-wise HS code tariff relief What are the main precautions and functions of lightning protection grounding in the weak motor room?
• 2、Design and construction of building lightning protection grounding system

What are the main precautions and functions of lightning protection grounding in the weak motor room?

The grounding wire between each wiring or the secondary junction is welded with a multi-strand copper core grounding busbar, and then connected to the grounding body. The ground wire should be located in the center of the building as much as possible.

Installation of lightning rods: Lightning rods are the first line of defense against lightning in the computer room. Installing a lightning rod on the roof of the machine room can effectively absorb and disperse the charge of lightning, thus protecting the equipment in the machine room.Installation of lightning protection equipment: In addition to lightning rods, lightning protection equipment needs to be installed in the computer room, such as lightning protection sockets, lightning protection boxes, etc.

How to take anti-static measures for computer equipment? ( Non-household precautions) Good grounding, maintaining normal air humidity, anti-static floor. What measures should be taken to achieve thunder and lightning weather and the normal use of computers and other weak electrical equipment?

The fifth is to ensure that the building has good grounding and reduce the contact potential damage to the equipment when lightning strikes the building. Internal protection of weak current systems: From the perspective of EMC (electromagnetic compatibility), lightning protection should be divided into multi-level protected areas from the outside to the inside.

The comprehensive factor of weak current lightning protection requires the unified consideration of external lightning protection device and internal lightning protection device, focusing on all-round comprehensive lightning protection, and the computer roomComprehensive factors such as lightning protection, lightning electromagnetic pulse (LEMP) protection, equipment lightning protection, power supply system lightning protection, line lightning protection, grounding system, protection device and other comprehensive factors are taken into account.

Hello! Four aspects that need to be done for lightning protection and grounding in the computer room, for reference: Considering the interference of lightning or other telecommunications equipment, the computer room should not be set up on the top floor of the building or on the side of the outer wall. If special circumstances are limited, a shielding layer should be set up to prevent lightning interference.

How to ground the power lightning arrester in the computer room

The introduction of three-phase electric connection is open to the introduction end. The three-phase of the empty output terminal is connected to the three red label modules respectively. If it is a box made by the manufacturer, then it is necessary to empty the right red grounding line to lead out a line of no less than 16 flat wires to the general grounding row of the computer room.

Lightning protection grounding can completely use the rebar in the building foundation as the grounding body, but the rebar must be electrically welded, and the vertical steel bar in the column of the house must be used as a lead-down line, which is always connected to the roof lightning protection facility.

That is, the grounding of the lightning protection system in the computer room is generally buried underground with horizontal wiring and vertical grounding piles, mainly to direct the lightning current from the lightning device to the grounding device, which should not be greater than 10 ohms. The lightning protection device can be divided into three basic parts: the flasher, the lead line and the grounding device. The flasher is the metal conductor that receives the lightning current.

When building or rebuilding a new machine room, the rebar in the concrete column can be used as a grounding device.

There are four grounding methods for the grounding system of the computer room. Why?

1. Grounding and zeroing are divided into four ways according to their functions: working grounding, protective grounding, lightning protection grounding and anti-static grounding. These methods are all grounded or zeroed to ensure the safety of people and equipment.

2. Lightning protection grounding, protection grounding, working grounding, shielding grounding. Lightning protection and grounding are divided into two concepts: one is lightning protection, which prevents damage caused by lightning strikes;The second is electrostatic grounding to prevent the damage caused by static electricity.

3. There are four forms of grounding in the computer room, namely: computer-specific DC logic ground, AC working ground, security protection ground, and lightning protection ground. Computer room grounding system Install a copper network under the mobile floor of the computer room, and connect all the uncharged housings of all computer systems in the computer room to the copper network and introduce them into the earth.

4. There are five kinds, and the grounding purpose, grounding method and grounding effect are different. The details are as follows: protective grounding. The safety grounding of the shell is to form a good conductive connection between the metal parts (cabinet shell, operating table shell, etc.) in the system that are usually uncharged with the ground to protect the equipment and personal safety.

5. Install security devices nearby (9) All communication equipment and power supply equipment in the computer room areThe metal parts that are often not charged, the grounding end of the lightning protection device set up by the communication equipment and other metal components should be grounded for protection, and it is strictly forbidden to use zero protection.

6. Grounding system The grounding of the computer room has four grounding methods, including lightning protection grounding, AC working grounding, safety protection grounding, and DC working grounding.

Design and construction of building lightning protection grounding system

The lightning protection grounding system of buildings should be composed of internal lightning protection grounding device and external lightning protection grounding device. The natural grounding body uses the horizontal rebar of the foundation base plate to form a grounding network, which is connected to the steel bars around the edge of the groove to form a closed loop to form a natural grounding body. This has the characteristics of: economical, practical, reducing grounding resistance and equalizing potential.

The construction requirements for lightning protection grounding of buildings include the following aspects: the setting of the grounding device: the grounding device includes grounding poles and grounding wires, which should be set according to the design requirements. The material and specifications of the grounding pole should meet the standard requirements, and the material and specifications of the grounding wire should also meet the standard requirements, and should be firmly connected to the grounding pole.

To prevent lightning and grounding, first probe the surrounding topography, understand the project overview, and then prepare materials, appliances and personnel. If it is for indoor use, the indoor use is mainly used for electrical grounding in power equipment. The wiring clip adopts a flat spiral, and the grounding method adopts a grounding wire clamp (connecting busbar and Copper row type).

Before analyzing the 8 technical points, let's take a look at the requirements of construction materials: galvanized round steel for lightning protection grounding systems,Galvanized flat steel, galvanized angle steel and other materials must be hot-dip galvanized parts. The variety specifications should meet the requirements of design drawings and profile standards, and have a material inspection certificate and a factory qualification certificate.