A lightning protection system

Abstract

A lightning protection system comprises two parts, i.e., an active lightning protection part and a passive lightning protection part. Active lightning protection: the lightning signal sent from the atmospheric electric field monitoring circuit is sent to the input terminal of the field effect transistor MOS1 through the resistor R1, and then to the input terminal of the field effect transistor MOS2 through the resistor R4. The lightning signal is sent to the input terminal of the field effect transistor MOS1 through the resistor R4. When there is no lightning signal, the input terminals of MOS1 and MOS2 are high potential, MOS2 is on, the output terminal of photoelectric coupler IC1 becomes low resistance, and the counting circuit judges that there is no lightning signal. When there is a lightning signal, the input terminals of the field effect transistor MOS1 and the field effect transistor MOS2 are low, FET MOS1 and FET MOS2 are cut off immediately, micro relay J1 and micro relay J2are powered off, contacts are disconnected, antennas of equipment are disconnected, network cable connection is disconnected, POE power supply is powered off, and transmission equipment stops working,so as to achieve the purpose of protecting transmission equipment; and passive lightning protection consists of three parts: power supply lightning protection, antenna lightning protection and signaltransmission.

Description

technical field [0001] The invention belongs to the technical field of lightning protection, and in particular relates to a lightning protection system. Background technique [0002] Many of the current wireless transmission equipment, such as broadcasting equipment, TV relay equipment, mobile cellular network equipment, etc., are installed on relatively high roofs, towers, mountain tops, etc., which are more vulnerable to lightning strikes than other low places. In the periphery of these devices, lightning rods, lightning protection belts, etc. are generally installed for lightning protection. Inside or outside the equipment, the lightning protection devices used are mainly composed of passive and passive components such as discharge tubes, Zener diodes, and varistors. Gas discharge tubes are usually used at the front end of equipment circuits, which have a good lightning protection effect, but expensive signal transmission equipment and receiving and transmitting equipmen...

AI Technical Summary

Problems solved by technology

Sometimes the induced lightning is too strong, and the components of the lightning protection circuit cannot absorb the lightning energy, which will also cause lightning damage to the equipment and damage to the lightning protection components themselves

[0004] On the other hand, because the equipment in the ground computer room is far away from the transmitting transmission equipment, generally more than tens of meters, high-quality network cables are generally used to transmit signals and supply power (POE power supply mode), but due to the low voltage of transmission signals, Only 1-3V, the signal attenuation is large, the anti-interference ability is poor, and there will still be frequent data packet loss and insufficient network speed (for example, gigabit transmission suddenly drops to 100M transmission), if the transmission distance exceeds 100 meters, It is basically powerless to use the network cable to transmit

[0005] In the way of POE power supply, there is a contradiction between the lightning protection voltage (several V) of signal transmission and the lightning protection voltage (75V) of power supply. Now the POE network cable arresters on the market are generally designed according to the lightning protection voltage of 75V. The lightning induced voltage between several V-75V on the signal line cannot be prevented, which is also one of the reasons why the equipment is damaged by lightning

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