Influence of different impulse waveforms on coordination of two cascaded SPDs

The installation of surge protection devices (SPDs) is important for the protection of low-voltage electrical equipment against in-rushing surge. This paper simulated the actual situation of electrical equipment protected by two SPDs, one is installed on the distribution panel at the entrance of a house or a building, and another SPD is added inside the equipment or in the socket. The coordination of these two cascaded SPDs were discussed when different impulse waveforms are considered. It is found the parameters selections for different impulse waveforms may need to be different.