10 350 μs Current Wave
This type of voltage wave is used to verify equipment s withstand to overvoltages of atmospheric origin impulse voltage as per iec 61000 4 5.
10 350 μs current wave. The term class is also commonly used. Iimp impulse current of 10 350 μs waveform associated with type 1 spd s in surge current of 8 20 μs waveform associated with type 2 spd s up the residual voltage that is measured across the terminal of the spd when in is applied. Carry a direct lightning current of 50 75 or 100 ka of waveform 10 350 μs and additionally inductive coupled currents with a waveform of 8 20 μs and a maximum value of up to 150 ka. The waveshapes used in testing surge diverters are 4 10 and 8 20 μs the figures respectively representing the nominal wave front and wave tail times see fig.
Iimp impulse current of 10 350 μs waveform associated with type 1 spd s. Waveform with a 10 350 s waveshape that is intended to simulate a direct lightning strike 2 in march 1992 i made some numerical models of this lightning test waveform propagating in a network of cables and two varistors 3 i used the following equation to represent the current i in the 10 350 s wave. The overvoltages created by lightning strokes are characterized by a 1 2 50 µs voltage wave see fig. I a i p t 1 10 exp t 2 1 t.
Apart from the standard impulse current waves rectangular waves of long duration are also used for testing. Type surge protection devices are classified into types according to their discharge capacity. Peak current with 10 350 μs waveform which the protection device can withstand without reaching end of life. Up the residual voltage that is measured across the terminal of the spd when in is applied.
The iec 61643 11 standard specifies a test program which includes both waveforms as well as a sinusoidal follow current of up to 100 a that. Type 2 in peak current in 8 20 μs waveform the protection device. There is some validity in the proposal of 10 350 as a test wave sometimes cited as a solution in search of a problem for some marketing approaches but if wg 3 6 4 would instead of arguing about duplicating lightning versus show me a recording of 10 350 propose and accept the arbitrary 10 350 as a useful spd characterization test actually the scope of 3 6 9 we might succeed in. The iec ieee 8 20 us waveform is an approximation of the surge current waveform experienced for induced lightning effects.
Uc the maximum voltage which may be continuously applied to the spd without it conducting. In order to avoid destruction of eut and adjust 10 350 μs impulse current test waveform to satisfy the requirement of iec61643 1. The iec ieee 10 350 us microsecond waveform is an approximation of the surge current waveform experienced for a primary lightning strike. 2005 standard a combined test simulate generator setting method.
The peak value of the current wave characterizes the intensity of the lightning stroke.