SPD normative definition

Why is Iimp important?

IEC 62305 standard requires a maximum impulse current value of 25 kA per pole for three-phase system. This means that for a 3P+N network the SPD should be able to withstand a total maximum impulse current of 100kA coming from the earth bonding.



Type 2 SPD

Imax: Maximum discharge current

This is the peak value of a current of 8/20 s waveform that the SPD is capable of discharging once.