Failure of electrical and electronic systems are due to insulation breakdown or when over voltages exceed the equipment’s insulation withstand level. Equipment is protected if its rated impulse withstand voltage UW at its terminals is greater than the surge overvoltage.

Coordinated SPD’s installed in the electrical system provide protection against conducted surges. Shielding and Routing of power and data lines, Bonding of Services at various Lightning Protection Zones (LPZ) & Earthing plays major role in protecting electrical and electronic equipment from radiated surges.