A surge protector (or spike suppressor, surge suppressor, surge diverter, surge protection device (SPD) or transient voltage surge suppressor (TVSS) is an appliance or device intended to protect electrical devices from voltage spikes in alternating current (AC) circuits. At the same time, Surge protectors are also widely used in DC photovoltaic (PV) systems for less than or equal to 1500VDC.