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Lightning surge test and lightning surge protection device

36 Sidall Structure Voltage switching type ac lightning surge protector (10/350μs)

Lightning surge test and lightning surge protection device

Lightning surge test is to evaluate the performance of power supply port, signal and control port of electronic and electrical equipment when subjected to surge (impact) interference. Its purpose is to evaluate the performance of the product when the equipment is subjected to high energy surge (impact) disturbance from power lines and interconnection lines.

There are two types of lightning surge tests: common mode and differential mode. Therefore, the use of surge absorbing devices should take into account the corresponding conditions with the test. In order to ensure the use effect, the surge absorbing device shall be used at the inlet of the incoming line. Due to the large di/dt in the surge absorption process, no signal line and power line can pass near the device to prevent electromagnetic coupling from introducing interference into the signal and power lines.

In addition, the pin of the surge absorbing device should be short; The absorption capacity of the absorption device shall match the test level of the surge voltage and current.

The biggest feature of lightning surge test is that the energy is particularly large. Therefore, the scheme of using ordinary filter and ferrite core to filter and absorb is basically invalid; Gas discharge tubes, varistors, silicon transient voltage absorbing diodes, semiconductor discharge tubes and other special surge protection devices must be used. A common characteristic of surge suppression devices is that the impedance is different with and without surge voltage. Under normal voltage, its impedance is very high, which has no effect on the operation of the circuit; When a very high surge voltage is applied to it, its impedance becomes very low, bypassing the surge energy. This kind of device is used in parallel between the line and the reference ground. When the surge voltage occurs, it will conduct quickly to limit the voltage amplitude to a certain value. Varistors, transient suppression diodes and gas discharge tubes have different volt ampere characteristics, so the changes when surges pass through them are not recognized.

The surge protection expert Zhejiang leihao Electric Co., Ltd. Laboratory provides free sites and equipment for customers to conduct lightning surges. Professional FAE engineers are nearby to provide technical guidance and help with the selection of surge protection devices. To learn more about lightning surge protection schemes and devices, please go directly to the Leihao electronic website to consult online customer service.

https://www.zjleihao.com/