How Does Surge Suppression Work?
The major design goal is to divert as much of the transient energy away from the load as possible by providing a lower impedance path and then to address the effects of the surge with the components of the SPD. Various types of surge suppression components are used to provide this low impedance pathway, depending on the specific application of the device. The most common component found in AC voltage devices is the Metal Oxide Varistor (MOV). Under normal conditions the MOV presents itself as a high impedance element. However, when the voltage level rises to a level exceeding the threshold of the MOV, the resistance of the MOV drops rapidly (within nanoseconds) providing a low impedance path of flow. The MOV has become the component of choice in AC power applications (over 95% of AC SPD’s use MOV’s) because of its high energy handling capability and reliable clamping performance. To enhance the performance of the tried and true MOV, we incorporate other components in our SPD’s. This Hy
