Need for Surge Protection Devices at Home

Most of us may not be aware of the surges and the impact of surges on our electronic devices.

At our home we may not have an SPD installed and most of the electricians may not know about it as well

It is often heard that the devices at home like TV, Music system, Laptop chargers or other costly devices fails frequently.

It is a fact that more than 40% of the television failure is due to the power quality, the major cause being the surge.

What is surge?
As the name indicates it is an impulse of energy of high magnitude that gets into the supply (mains). The impulse is distructive enough to damage the equipment.

How surge occur?
There are several factors that causes surge. It could be because of 1) Lightning that hits the power distribution lines 2) energy kicked in due to some heavy machines starting up 3) Capacitor banks switching 4) Electrical arcs 5) Welding and cutting machines

What is surge protection devices (SPD)?
Surge protector is nothing other than a Metal Oxide Varistors (MOV). The device helps to clamp the high.magnitude energy.
When the surge is beyond the MOV ratings, MOV fuses that results in shorting the MOVs. A fuse in breaker in series breaks / blows there by disconnecting the unit.
Another catagory of MOV is TPMOV(Thermally Protected MOV). These devices, instead of shorting the terminals, would automatically disconnect from mains when fuses due to surge. Such devices do have a visual indication or a potential free contact (mechanically driven) for detection of the failure (when fused).

SPD category?
There are two categories of SPD based on surge
1) Type 1:- For direct lightning surges. These SPD discharge / clamp the surge energy using spark gaps. Type1 SPD needs separate lightning arrestor earthing for the reliable functionality.
2) Type2 - For indirect Lightning and surges caused due to machineries.

There is another category as well which is Type1+Type2 ( combination of both).

Do we need an SPD at home?
Yes we need it badly. Surges are not predictable and could happen any time. SPD in the electrical distribution would guard the costly equipments.

SPDs are available in DIN rail mount packages which could be installed at in the distribution boxes.