13 July 2010

Power Surge Protection for the whole house

FORGET THOSE plug in surge protection adapters available from the local DIY store, they only provide protection to those items plugged directly in to them, usually just the PC. What about the air conditioning units, the washing machine, and all the other appliances in the house?

When a power surge strikes it shows no mercy and will destroy every appliance in the property. You need whole house surge protection provided by a Surge Protection Device (SPD) fitted to protect the entire electrical installation.. This is the only way to protect everything in the home from the merciless power surge.

What is a power surgeA power surge is a sudden and unwanted increase in voltage that can damage or destroy electrical equipment. They burn out chips (Integrated circuits) and PCB's (Printed Circuit Boards), which exist in practically every piece of modern day electrical equipment where they are not designed to withstand excess voltages. Power surges come in two forms, the first is caused by the switching of the electricity supply network from high powered electric motors and transformers, or in the case of a temporary builders supply from on-site generators or faulty wiring. In addition hundreds of transient spikes occur daily from devices in the home or work place. The second is by lightning and electrostatic discharges, more common in rural properties but can also mercilessly strike any individual property on an urbanisation, commercial or industrial estate. In industry the damage and failures due to power surges are estimated to be in the range of hundreds of millions of Euros.

Each year about 2 million flashes of lightning occur on the Iberian Peninsula. Lightning protection systems should be installed on tall buildings, cultural heritage buildings, warehouses with dangerous materials and open sites used by the public, necessary for structural and personal safety. Lightning can strike a building directly, the ground nearby or even overhead power lines miles away and cause power surges. Mains electric cables plus TV/Sat and telephone cables which enter from the outside of a building act as conductors for lightning strikes and can facilitate the way for power surges and require protection devices against these transients.

Dual split-load CU with SPD
For whole house surge protection an SPD should be installed in the Consumer Unit, and to the TV/Sat and
telephone outlets. The device works in one of two ways, either by diverting the current generated by the power surge directly to earth, or by disconnecting the mains supply to the installation, preventing the power surge passing through the equipment. The former type usually being most preferable because it is fully automatic and does not require someone to switch the supply back on. Multi-adapter extension leads fitted with an SPD, like those available to purchase in DIY stores, only provide minimal protection for a limited number of items, when a power surge strikes it shows no mercy and may strike every electrical appliance in your property on a search and destroy mission. Air conditioning units are very prone to damage from power surges as well as computer equipment and TV's. Most air conditioning and TV satellite installation companies will not guarantee their equipment unless it is protected by a SPD. An RCD (aka Interruptor Differencial) does not provide protection against power surges. For a complete safeguard against power surges a whole house surge protection system is required.

Surge Protection Devices are recommended for properties with sensitive and expensive electrical and electronic equipment such as air conditioning, microwaves, ovens, washers and dryers, computers, printers, TV cinema systems, hi-fi, even lighting, practically every appliance in your home. They are also strongly recommended for installations in rural areas supplied with Solar Energy Systems exposed to high risks of lightning. Make sure you protect your expensive electronic equipment.

A final piece of advise is to check your building insurance policy to see if you are covered for power surges.

Here is a just a small selection of SPDs that Sparks recommend.

A simple single module SPD fitted in the main Consumer Unit that provides protection from surges on the mains power supply. It disconnects the electricity supply at the RCD when the voltage surges at 260 volts + or - 2% (255-265 volts). This type of SPD requires the electricity supply to be switched back on to restore power in the event of a power surge. The SPD is fitted with a test button and LED indicator. The device requires one available hole in the Consumer Unit in order to be fitted.

A double module SPD fitted in the main Consumer Unit that provides protection from surges on the mains power supply. It directs external and internal power surges directly to earth. This type of SPD is fully automatic and causes no interruption to the power supply. The SPD is in two parts with a thermal cut-off unit with visual display. An indicator on the cartridge unit shows green for OK, and red if it needs to be replaced. The device requires two available holes in the Consumer Unit to be fitted. 

SPD's for telephone and TV/Satellite installations. These are fitted adjacent to the cable entry points in the property onto the incoming telephone cable and TV/Satellite cable. Power surges can enter a building from any external conductor as electrostatic discharges caused by lightning. Requires a socket outlet next to the telephone and TV/Sat point to power the SPD.

The SPDs featured are 230 volt single-phase devices. 3-phase SPDs are also available.

Other SPD's recommended and installed by Sparks are manufactured by Cirprotec.