Surge Protection Devices
Lightning surges frequently cause failure of electrical and electronic systems due to insulation breakdown or when over voltages exceed the equipment’s common mode insulation level. Equipment is protected if its rated impulse withstand voltage UW at its terminals is greater than the surge over voltage between the live conductors and earth. If not, an SPD must be installed. Surge Protection systems MUST be compliant to IS / IEC 62305 and NBC 2016.
Implementing coordinated SPD’s will provide protection against radiated surges. Shielding and Routing of power and data lines, Bonding of Services and various Lightning Protection Zones (LPZ) & Earthing also plays major role in protecting electrical and electronic equipment.
SPD’s are used to protect under specified condition, electrical systems and equipment against various over voltages and impulse currents such as Lightning and Switching Surges. SPD shall be selected according to their environmental conditions and the acceptable failure rates of the equipment and the SPD’s.
There are different types of SPDs:
- Power Line SPDs(Main Electrical Line, distribution panels etc)
- Signal Line SPDs(TV, Phone, Network CCTV etc)