Surge Protection

Surge Protection: Lightning and Electronic Equipment and System

Technological advances in the past ten years have resulted in people and businesses becoming increasingly reliant on sophisticated electronic devices to conduct business, for entertainment and even feel safe and secure in our environment.

But having computers, entertainment systems, video surveillance equipment as well as electronic appliances in our offices and homes have also made us more vulnerable to one of the most common natural disasters: lightning. The Highveld and Lesotho are areas that are particularly prone to lightning with some of the highest lightning strikes in the world.

With a high percentage, which some experts attribute to between 65% -80%,  of damage to electronic equipment being caused by lightning and voltage surges, disruptions in the form loss of communication and data loss as well as the sheer inconvenience of broken equipment and appliance can have serious impact on businesses. But with the correct protection the effect of lightning can significantly be reduced.

Recent adoption by the South Africa Bureau of Standards SANS 61024-1 {protection of building structures against lightning and electro magnetic pulses} and SANS 61312-1 {protection of information systems against lightning and electro magnetic pulses} now makes it possible to design protection systems that will greatly increase the reliability of installed electronic equipment and limit damages caused by lightning and electro magnetic pulses.

How does Lightning Affect Electronic Systems ?

Galvanically coupled surge voltages:

Lightning can strike the air conductors directly and surge voltages, even from kilometres away, can enter into your electrical network. This surge voltage is then passed to ground through your appliances and electronic devices which can damage or completely destroy your equipment.

Induced surge voltages:

When lightning strikes an object,  high currents at fast wave fronts occur causing large electromagnetic fields which are then induced into your electrical and data communication cabling. Equalisation then occurs which could cause damage to your equipment.

Earth potential differences

When lightning strikes a structure, (a building, tree or pole etc.) a high voltage potential exists for the duration of the strike at the point of contact of the structure to the ground. Due to resistivity of the earth, decreasing voltage potentials will be experienced along the current paths moving away from this point. Should you have electronic equipment referenced to different earth systems while connected to each other via copper cables, equalisation will tend to occur via the copper cables resulting in equipment damage.

At Dan Electrical our objective is to provide our customers with an effective surge protection solution at affordable costs.