FEATURE: SURGE PROTECTION | SPARKS
HOW SPDs WORK Surge Protection Devices (SPDs) are specifically designed to protect electronic equipment from extremely short duration high voltage spikes. BEAMA explains more in this article.
“AN SPD DIVERTS THE SURGE CURRENT TO EARTH AND LIMITS THE OVERVOLTAGE TO A SAFE LEVEL.”
T
he operation of electronic systems can be severely affected by lightning activity or electrical switching events. Both can cause short duration high voltage spikes or transients on mains power and/or data communication/signal/telephone lines, with potentially devastating consequences to installed equipment. These increases in voltages are called surges or transient overvoltages. An SPD diverts the surge current to earth and limits the overvoltage to a safe level.
THE SOLUTION
Circuit breakers/fuses are designed to protect your home, business, equipment, and possibly even your life from an event such as a short circuit or overload. They are not designed to provide overvoltage protection. This protection is provided by SPDs which are specifically designed to redirect the harmful voltage away from the equipment.
HOW SHOULD SPDS BE INSTALLED?
SPDs are connected to the power supply in parallel with the load circuits that it is intended to protect. Depending on the type selected, SPDs are typically installed at the supply input point, the distribution board or near the equipment to be protected. Reputable manufacturers provide tailored solutions for various applications. To find out more about the BEAMA Manufacturers Trade Association go to: www.beama.org.uk
WHAT DO THE WIRING REGULATIONS STATE?
In brief, the Wiring Regulations (BS 7671) state that adequate protection for both people and equipment from transient overvoltages of atmospheric origin transmitted via the supply distribution system and against switching overvoltages must be provided.
How do I find more information? ■ Study sections 443 and 534 of the Wiring Regulations ■ Read the BEAMA Guide to SPDs Selection, Application and Theory.
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