According to the language No.43 [2] of the Ministry of Construction, the letter agreeing to compile the Technical Specification for Lightning Protection of Building Electronic Information System was organized and set up by the Sichuan Provincial Construction Department (the former Construction Committee). After referring to relevant standards at home and abroad, the specification was formulated after earnestly summing up practical experience and soliciting opinions from all parties.
this specification is divided into 8 chapters and 4 appendices. The main technical contents are as follows: 1. General rules; 2. Terminology; 3. Lightning protection zoning; 4. Lightning protection classification; 5. Lightning protection design; 6. Lightning protection construction; 7. Construction quality acceptance; 8. Maintenance and management.
this specification mainly specifies and requires the design, construction, acceptance, maintenance and management of the comprehensive lightning protection project of microbial electronic information system.
the provisions marked in bold type in this specification are mandatory and must be strictly implemented. The Ministry of Construction is responsible for the management and interpretation of the mandatory provisions of this Code, and the Sichuan Provincial Construction Department is responsible for the specific management, and the interpretation of the specific contents of China Building Standard Design and Research Institute and Sichuan Zhongguang High-tech Research Institute Co., Ltd. In the process of implementation, all units are requested to sum up their experience in combination with the engineering practice. If there is any need to modify or supplement, please send your comments and suggestions to the Construction Department of Sichuan Province (Address: No.36, Section 4, Renmin South Road, Chengdu, Sichuan, Postal Code: 6441).
1? General provisions
1..1 this specification is formulated to prevent and reduce the harm of lightning to the electronic information system of buildings and protect people's lives and property safety.
1..2 this specification is applicable to the design, construction, acceptance, maintenance and management of lightning protection for electronic information systems of newly built, expanded and rebuilt buildings.
this specification is not applicable to lightning protection of electronic information systems in inflammable and explosive dangerous environments and places.
1..3 in the lightning protection design of building electronic information system, external lightning protection measures and internal lightning protection measures should be coordinated and unified according to the characteristics of building electronic information system, and comprehensive planning should be carried out according to the overall requirements of the project, so as to achieve safety, feasibility, advanced technology and economy.
1..4 the lightning protection of electronic information system must adhere to the principle of putting prevention first and safety first. When necessary, the site lightning electromagnetic environment can be evaluated before design.
1..5 the electronic information system should be comprehensively protected by external lightning protection and internal lightning protection (fig. 1..5).
1..6 the lightning protection of electronic information system should take corresponding protective measures according to environmental factors, lightning activity law, lightning protection zone where the equipment is located, immunity of the system to lightning electromagnetic pulse, damage degree of lightning accident and importance of system equipment. ? 1..7 Lightning protection of building electronic information system shall conform to the relevant national standards in addition to this specification.
2? The term
2..1 electronic information system? electronic? information? System
is a man-machine system which is composed of computers, wired/wired communication equipment, processing equipment, control equipment and electronic equipment such as matching equipment and facilities (including networks), and processes information according to certain application purposes and rules.
2..2 electromagnetic compatibility? electromagnetic? Compatibility(EMC)
A device or system can work normally in its electromagnetic environment, and it does not cause unbearable electromagnetic interference to other devices and systems in the environment.
2..3 electromagnetic shielding? electromagnetic? Shielding
a shield that uses conductive materials to reduce the penetration of alternating electromagnetic fields into designated areas.
2..4 lightning protection device? lightning? protection? System(LPS)
external and internal lightning protection devices.
2..5 external lightning protection device? external? lightning? protection? System
is composed of lightning receptor, down conductor and grounding device, which is mainly used as a protective device against direct lightning.
2..6 internal lightning protection device? internal? lighting? protection? System
is composed of equipotential connection system, grounding system for * * *, shielding system, reasonable wiring system, surge protector, etc. It is mainly used to reduce and prevent the electromagnetic effect caused by lightning current in the space to be protected.
2..7*** common grounding system? earthing? System
a grounding system that connects lightning protection devices, building metal components, low-voltage distribution protection lines (PE), equipotential bonding belts, equipment protection grounds, shielding grounding, anti-static grounding and grounding devices.
2..8 equipotential bonding? equipotential? Bonding(EB)
the electrical connection of the exposed conductive parts of equipment and devices with basically equal potential.
2..9 equipotential bonding belt? equipotential? bonding? Bar(EBB)
a metal belt to which metal devices, foreign conductors, power lines, communication lines and other cables are connected to make equipotential connection with lightning protection devices.
2..1 natural grounding body? natural? earthing? Electrode
is a general term for all kinds of metal components, metal well pipes, steel bars in reinforced concrete, buried metal pipes and facilities which are used as grounding but not specially set for this purpose and have good contact with the earth.
2..11 earthing terminal? Terminal
will protect adipic acid, including the terminal or grounding bar where the equipotential bonding conductor and the conductor of working grounding (if any) are connected to the grounding device.
2..12 main equipotential connection terminal board? equipotential? earthing? terminal? Board(MEB)
a metal plate that connects a plurality of grounding terminals together.
2..13 floor equipotential grounding terminal board floor? equipotential? earthing? terminal? Board(FEB)
in the building, grounding terminal boards are set on floors for equipotential connection of local equipotential grounding terminal boards. ? 2..14 Local equipotential grounding terminal board? local? equipotential? earthing? terminal? Board(LEB)
in the equipment room of electronic information system, the grounding terminal board is used for local equipotential connection.
2..15 equipotential bonding network? Network(BN)
a network composed of conductors whose exposed conductive parts are equipotentially connected.
2..16 surge protector? protective? Device(SPD)
should include at least one nonlinear voltage limiting element, which is used to limit transient overvoltage and shunt surge current. According to the function of surge protector in electronic information system, it can be divided into power surge protector, antenna surge protector and signal surge protector.
2..17 voltage switching surge protector voltage? switching? type? SPD
is a surge protector composed of discharge gap, gas discharge tube, thyristor and triac. Usually called switching surge protector.
2..18 voltage-limited surge protector voltage? limiting? type? SPD
adopts surge protector composed of piezoresistor and suppression diode. It is usually called voltage-limiting surge protector.
2..19 lightning protection zone? protection? Zone(LPZ)
the area where lightning electromagnetic environment needs to be defined and controlled.
2..2 integrated lightning protection system? synthelical? protection? against? lightning? System
The building is a lightning protection system consisting of external and internal lightning protection measures.
2..21 lightning electromagnetic pulse? electromagnetic? Impulse(LEMP)
As the interference source, lightning current and the electromagnetic field effect produced by lightning electromagnetic field.
3? Classification of thunderstorm days in lightning protection zoning
3.1
3.1.1 The classification of thunderstorm days in the area should be based on the annual average number of thunderstorm days.
3.1.2 The thunderstorm days in the area should be classified into less minefield, more minefield and higher minefield, and the following requirements should be met:
1 Less minefield: the area with an annual average thunderstorm day of 2 days or less;
2. More minefields: areas where the annual average thunderstorm days are more than 2 days and less than 4 days;
3. High minefield: the area where the annual average thunderstorm days are more than 4 days and not more than 6 days;
4 strong minefields: areas with annual average thunderstorm days over 6 days.
3.1.3 the number of thunderstorm days in the region shall be based on the local average annual thunderstorm days published by the state, as shown in appendix D ..
3.2 Division of Lightning Protection Zone
3.2.1 Division of Lightning Protection Zone is to divide the buildings that need to be protected and control the lightning electromagnetic pulse environment into different lightning protection zones (LPZ) from the outside to the inside.
3.2.2 The lightning protection zone shall be divided into: direct lightning protection zone, direct lightning protection zone, first protection zone, second protection zone and subsequent protection zone (Figure 3.2.2), and meet the following requirements:
1? Unprotected area of direct lightning (LPZA): The electromagnetic field is not attenuated, and all kinds of objects may be directly struck by lightning, so it is a completely exposed unprotected area.
4? Direct lightning protection zone (LPZB): The electromagnetic field is not attenuated, and all kinds of objects are rarely struck by direct lightning, so it is a fully exposed direct lightning protection zone.
5? The first protection zone (LPZ1): Due to the shielding measures of buildings, the lightning current flowing through various conductors is less than that of the direct lightning protection zone (LPZB), and the electromagnetic field is preliminarily attenuated, so that various objects cannot be directly struck by lightning.
6? Second protection zone (LPZ2): a subsequent protection zone introduced by further reducing the guided lightning current or electromagnetic field. ? 7? Subsequent protection zone (LPZn): It is necessary to further reduce the lightning electromagnetic pulse to protect the subsequent protection zone of the equipment with high level of the third degree.
4? Classification of lightning protection
4.1 General provisions
4.1.1 The lightning protection grade of building electronic information system should be divided into four levels: A, B, C and D according to the interception efficiency of lightning protection devices.
4.1.2 lightning protection levels shall be classified according to one of the following grammars:
1? According to the environment where the building electronic information system is located, the lightning protection level is determined to be
2? Determine the lightning protection level according to the importance and use nature of the building electronic information system.
4.1.3 For particularly important buildings, it is advisable to use the two grammars specified in Article 4.1.2 for lightning protection classification, and determine the higher protection level.
4.2 Determine the lightning protection level according to the lightning strike risk assessment
4.2.1 Determine the value of n (times/year) according to the estimated annual lightning strike times N1 of buildings and N2 of buildings' access facilities, where N=N1+N2 (see Appendix A for calculation grammar).
4.2.2 The acceptable annual average maximum number of lightning strikes due to direct lightning and lightning electromagnetic pulse damage to building electronic information system equipment can be calculated as follows: NC=5.8×1-1.5/C (times/year). See appendix a for calculation grammar.
4.2.3 compare n and NC to determine whether the electronic information system equipment needs to be equipped with lightning protection devices:? 1? When N
2? When N> When NC, lightning protection device should be installed.
4.2.4 determine the lightning protection level according to the calculation formula E=1-NC/N of the interception efficiency e of the protection device:
1? When E> .98 hours? Set it as grade a
2? When .9
3? When .8
4? When E≤.8? Grade d
4.3 lightning protection classification is determined according to the importance and use nature of building electronic information system
4.3.1 lightning protection grade should be selected according to table 4.3.1 for building electronic information system.
the above is the lightning protection and grounding specification for buildings, please read it carefully. Thank you for your concern about Tuba Rabbit Decoration Network.