Installation Regulations Of Surge Protectors In Gb50057 Standard

SPD lightning protection surge protector has developed to be a more mature product, with a smaller size, more stable and excellent performance, and more standardized installation standards.

In the national standard GB 50057-2010 Building Lightning Protection Design Specification, the installation regulations of SPD surge protector are explained:

1. Outdoor surge protective device should be installed at the connection between cable and overhead line. Surge protector, cable metal sheath, steel pipe and insulator iron foot, hardware, etc. should be connected together for grounding, and the impact grounding resistance should not be greater than 30Ω. The installed surge protector should be a Class I test product, and its voltage protection level should be less than or equal to 2.5kV, and each protection mode should have an impact current equal to or greater than 10kA; if there is no outdoor surge protector, an indoor surge protector should be selected, and its operating temperature should meet the ambient temperature of the installation location, and it should be installed in a box with protection level IP54. (P14)

2. A surge protection device of Class I test should be installed at the main distribution box where the power supply is introduced. The voltage protection level of the surge protector should be less than or equal to 2.5kV. When the impact current value of each protection mode cannot be determined, the impact current should be equal to or greater than 12.5kA. (P18)

3. When the outdoor line of the electronic system uses metal wires, a surge protector of Class D1 high energy test type should be installed at the terminal box where it is introduced. When the outdoor line of the electronic system uses optical cables, on the electrical line side of the terminal box where it is introduced, when there is no metal line leading out of the building to other equipment with its own grounding device, a surge protector of Class B2 slow rise rate test type can be installed. Its short-circuit current is determined according to the specification, and 100A is preferably selected. (P19)

4. When the electrical grounding device is shared or connected with the lightning protection grounding device, a surge protector of Class I test should be installed at the main distribution box and distribution cabinet where the low-voltage power supply line is introduced. The voltage protection level of the surge protector should be less than or equal to 2.5kV. The impulse current value of each protection mode, when it cannot be determined, should be equal to or greater than 12.5kA. (P25)

5. When the distribution transformer of Yyn0 or Dyn11 type connection is installed in the building or attached to the outer wall, a lightning arrester should be installed on the high-voltage side of the transformer; on the distribution panel on the low-voltage side, when there is a line leading out of the building to other distribution devices with independent grounding devices, a Class I test surge protector should be installed on the busbar, and the impulse current value of each protection mode of the surge protector should be equal to or greater than 12.5kV when it cannot be determined; when there is no line leading out of the building, a Class II test surge protector should be installed on the busbar, and the nominal discharge current value of each protection mode of the surge protector should be equal to or greater than 5kA. The voltage protection level of the surge protector should be less than or equal to 2.5kV. (P25)

6. A surge protector with a level II test should be installed on the power supply side of the switch in the distribution box. Its voltage protection level should not be greater than 2.5kV, and the nominal discharge current value should be determined according to the specific situation. (P32)

7. When a surge protector is required to be installed near the equipment to be protected, that is, at the interface of LPZ 2 or higher, a surge protector with a level II or III test should be selected for the electrical system, and the specific situation should be determined for the electronic system. (P56)

In summary, according to the installation requirements of the surge protector in the GB50057 standard of the national standard document, a surge protector with a suitable test level should be selected and installed in a location that meets the specifications to maximize the effectiveness of the surge protector.