![]() It can be seen that the above mentioned two kinds of experiments are totally different, which should not be confused. Since the equipment conducts the measurement in the on-line state, coupling and decoupling network should be used. In this way, the generator suitable for surge anti-interference measurement not only needs to have high output voltage, but also needs to have low output impedance and large energy output characteristics. Due to the low circuit impedance, the output impedance of the generator is also required to be low. On the contrary, IEC 6 standard requires conducting the surge anti-interference measurement. This kind of test is conducted in the off-line state of the equipment. At this moment, although the voltage of the generator is high, the energy is not huge. For example, high-pressure test also mentioned the lighting test for the impulse withstand voltage test with the high-pressure and high-resistance generator. Level X: Special level should be confirmed after the consultation of the user and the manufacturer.Selection of the product level depends on the product standard.Īt present, there are many standards mentioning the situation of using 1.2/50μs lighting to do the test, but the different standard has different test objective. Level 4: Severe harassment environment such as civil aerial, high-pressure power substation without protection. Level 3: Common electromagnetic harassment environment without specified installation requirement for the equipment such as the cable network of common installation, industrial work place and power substation. Level 2: Certain protective environment such as factories with no strong interference. Level 1: Better protective environment, such as the control room of the factories or the power station. The severe degree of the test depends on the environment (the environment that may suffer the surge) and the installation condition it is mainly divided into the following types: Each level parameter of the power circuit common mode test is 0.5kV、1kV、2kV、4kV and undetermined. Level 13 parameter of the power circuit differential mode is not given, the other levels are respectively 0.5kV、1kV、2kV and undetermined. ![]() The severe degree of the test can be divided into 1, 2, 3, and 4 and X level. In addition, the test voltage should be confirmed not to exceed the requirement of the product standard in order to avoid the unnecessary damage. (3) The voltage should be gradually tested from low level to high level to avoid the false scent of the sample I-V nonlinear characteristics. In general, there are five -times test for each positive and negative polarity. As a matter of fact, it is impossible for the natural lighting phenomenon and the large switch of the transformer substation to have very high repetition rate. It should not be too quick so as to form a recovery process for protecting the machine’s performance. (1)Protective measures must be taken in accordance with the requirement of the manufacturer before the test. The requirement of the generator line and the waveform is shown as the following figures: “Comprehensive wave” refers to the waveform parameters formed by the voltage wave and the current wave regulated by the standard in a surge generator circuit(when the output terminal of the generator is open circuit, it will form the voltage surge wave when the output terminal of the generator is short circuit, and it will form the current surge wave). (1)Comprehensive wave generator used for the power lines test The waveforms of the two kinds of surge are different because of the different line impedance. This standard has mentioned two kinds of surge generators, which respectively simulate the situation of the power line and the communication line. IEC 6 is a standard that provides an objective evaluation on the resistance to surge interference ability for the electrical and electronic equipment through the experiment of simulating lighting surge. The common characteristics of the two kinds of surge include high energy (compared with the energy, the static electricity is P joule level, pulse group is the millijoule level, lightning surge is hundreds of the joule level, which is one million times of the former two interfering energy), slow waveform (microsecond level, but the static electricity and pulse group are nanosecond level, even the sub nanosecond level), and low recurrence frequency. Besides, huge surge voltage and current will also be induced in the supply circuit of the instant switch in the power station or switching station. ![]() ![]() The entire lightning stroke in the nature (namely the indirect thunder such as the lighting stroke between the clouds, or the lighting stroke happened to the adjacent objects) can induce the surge voltage and current in outdoor aerial. ![]()
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