Lovato SPD Surge Protection Devices

SURGE PROTECTION DEVICES The surge arresters commonly defined as SPD (Surge Protection Devices), are devices designed to protect electric systems and equipment against transient and impulse overvoltage such as those caused by lightning strikes and by electric switching. Their function is to divert the discharge or impulse current generated by an overvoltage to earth/ground, thereby protecting the equipment downstream. SPD are installed in parallel with the electric line to be protected. At the mains rated voltage, they are comparable to an open circuit and have a high impedance at their ends. In the presence of an overvoltage, this impedance falls to very low values, closing the circuit to earth/ground. Once the overvoltage has ended, their impedance rises again rapidly to the initial value (very high), returning to open loop conditions. The SA1B and SA0B (monoblock) and SA0 (with plug-in cartridge) type protects against direct and indirect lightning strikes as well as induced overvoltage conditions. It can be installed in areas with a high risk of direct lightning strikes, inside main distribution boards or nearby sub-distribution boards.