I. Introduction With the rapid development of modernization construction and the wide application of power electronic technology, the threat posed by lightning is becoming more and more serious. Taking chemical enterprises as an example, there are many towering structures on site, which are easily invaded by lightning in thunderstorm weather Induced lightning current is generated on the internal power cables and signal cables, which is extremely harmful to the normal production of enterprises, and lightning safety protection measures have attracted the attention of users.

II. Although chemical companies conduct lightning protection inspections every year in accordance with GB/T 21431-2015 "Technical Specifications for Detection of Lightning Protection Devices in Buildings". However, during the thunderstorm season, the following problems still exist in operation:

1) The communication port of DCS or PLC instrument automation system is easily damaged;

2) The outdoor monitoring system of the tank farm is easily damaged;

3) The inverter is easy to trip. The user system is checked and found that there are still defects in the overall lightning protection comprehensive configuration, mainly including the following points: a) The corrosion of external lightning protection facilities (down conductors) is more serious; b) There are still many unreliable connections in the equipotential connection between the field equipment cabinet shell or passive conductive components, either unconnected or the connection line is loose; c) The on-site lightning protection wiring is unreasonable; d) Symbolic configuration of surge protector.