Analysis of lightning protection knowledge of intelligent instruments

With the continuous development of the world's science and technology, the demand for industrial automation and production, the intelligent instrument industry has developed rapidly. However, most of these intelligent instruments and meters with a large number of micro electric devices applied internally have problems such as low insulation strength and low surge resistance. Therefore, the lightning protection of intelligent instruments and meters is very important, especially in the rainy season, so as to avoid heavy losses caused by accidents.

The lightning protection of intelligent instruments and meters should start from two aspects, including external system lightning protection and internal system lightning protection, which are generally realized by adding lightning protection devices. The following four methods can be used for lightning protection.

1. Lightning protection starts from the grounding system. Enclosures of instruments, especially control cabinets, operation consoles and power cabinets, shall be connected together with flat steel. The working power supply of instrument, such as 24V negative terminal, shall be connected with instrument signal ground, computer input and output signal ground to form equipotential. The grounding of intrinsically safe grounding, safety barrier, isolation barrier and safety device shall also consider whether the instrument signal reference point is equipotential when connected.

2. The lightning protection of power supply of intelligent instruments cannot be ignored. Install surge protection system or surge protector for intelligent instruments and meters to ensure that the instruments and meters will not exceed the withstand voltage limit. The surge protector can send the overload current to the ground when it senses the lightning surge in thunderstorm weather.

3. Setting signal channel surge arrester for intelligent instruments can not only ensure accurate, stable and flexible information transmission, but also release overvoltage surges to the ground in thunderstorm weather to ensure the safety of signal transmission.

4. Regularly check and repair the power system grounding, bus bar, grounding body, surge arrester, power lightning barrier, etc. of intelligent instruments and meters, and timely replace them.