All Safety

The Need for Surge Protection

Are power surges a real risk to you and your belongings?

As Melbourne leaves behind a particularly hot summer for misty Autumnal mornings, conditions are matchless for sparking dangerous and destructive fires on power poles.

In the electricity distribution network, electricity is carried in wires that must be “insulated” from the poles which support these wires. This is achieved by supporting bare cables on insulators, which are in turn supported by the pole. These insulators are designed to ensure contaminants such as dirt and water can never accumulate to the point of providing a conductive path from the wire to the pole.

Under certain “perfect storm” conditions such as what much of Melbourne will soon experience, the insulator will be unable to keep itself clean. Dust and other particulate contaminants will have accumulated on the insulator due to the lack of heavy rainfall, and while not enough to wash the insulator, gentle mists and light showers will turn the formerly dry dust into a conducting soup of charged ionic particles. If the insulator fails and electricity leaks from one wire to another through the pole (or from one wire to the ground), parts of the pole can heat up to the point of catching fire.

If ever you have heard a crackling noise coming from a power pole, this is electrical current getting past the insulator and through the pole. Usually, it’s not too much, but it takes very little for that current to increase to the point of a fire starting in the pole.

Not only can such fires be dangerous in themselves (faulty electricity distribution equipment has started some of the most catastrophic bushfires in Victoria), they can (and often do) lead to power “surges” that cause thousands of dollars of damage to appliances and electrical wiring. Often, owners of such damaged property will never know that a power surge was responsible.

All it takes is, as a result of a pole fire, for a high voltage line to fall onto a lower low voltage line. Then, tens of thousands of volts could quite easily pass through your appliances that are designed to operate on between 220 and 240 volts. And who’s to say this couldn’t end up passing through yourself or someone dear to you?

Burned 22 kV distribution cross arm
Burned 22,000 volt cross arm. The lower wires are directly connected to your home or business.

For residents of bayside suburbs and the Mornington Peninsula, conditions are even more problematic. Sea salt is notorious for conducting electricity when mixed with a little water. Without wanting to criticise the fine work of the local distributor who work tirelessly to prevent this, Definite Electrical has noted burn marks on more than 8 poles in one suburb alone, visible for all to see. If we were to include the evidence which has been removed through pole and/or cross arm replacement, the number would be significantly higher.

Let’s not forget that pole fires are only one potential cause of power surges. Other potential causes, which each deserve an article to be written about them in their own right, include:

  • Lightning
  • Windy weather
  • Flora and fauna on powerlines
  • Traffic accidents
  • Vandalism
  • Transformer explosions
  • Substation faults

Of course, such an event need not take place directly in front of your property for this to be a problem to you. It could happen streets or even suburbs away, with the surge flowing effortlessly along the wire at close to the speed of light.

The solution?

Surge protectors are designed to redirect excessive voltages away from your property and harmlessly into the ground.

Definite Electrical can supply and professionally install a high quality surge protector in your switchboard.

By Stuart Graves

Stuart's been playing with electricity since infancy. After beginning his career with software engineering and IT support, Stuart has returned to his original passion with a mature age apprenticeship and electrician's qualification. This new career has since merged with the previous to provide experience with renewable energy management, automation, monitoring and all things electric vehicles.