The lightning surge test is a test item of EMS, which mainly tests the immunity of the equipment under test (EUT) to induced voltage transients caused by lightning. Because during the use of the EUT, when a lightning strike occurs, an induced peak voltage may be generated on the power line and the signal line. This voltage may cause the performance of the EUT to decrease or even be damaged. The lightning surge test is caused by the lightning surge. The device simulates and generates a spike voltage, which is coupled to the power line and the data line, and observe whether the EUT can work normally under such a large inductive pressure impact. Test purpose and index requirements Test purpose is to investigate the damage of the tested interface and the degradation of equipment performance after the subscriber line interface is impacted by surge voltage during actual use of the equipment. The following is an introduction to the precautions of the lightning surge generator experiment:

　　1 When using an oscilloscope, it is best to add an isolation transformer to supply power to prevent lightning surge and reverse surge voltage from experimenting with the power supply of the oscilloscope. The lightning surge recoil is generally 8% of the setting.

　　 2. Ensure that the lightning surge generator is grounded reliably.

　　 3. The power supply of the differential probe is best to use an isolation transformer to eliminate external interference to the test tool.

　　 4. The EUT power supply should preferably be powered by an isolation transformer, or an air switch with larger leakage protection.

5. Laboratory operation safety is the primary position. (Lightning surges have high voltage and high current experiments, which are dangerous). Try not to touch the wiring position during the test, and do not touch when the lightning surge generator triggers the discharge. For any connection line, if there is an emergency, press the emergency stop button directly, and the instrument will automatically unload the high voltage voltage.