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What is a Power Surge?

All Electrical Plus

It’s fair to say that most of us take electricity for granted. We also take it as a given that household electricity is safe, even though fundamentally, it’s basically the same stuff as lightning. 

We have made it safe and we continue to do work to maintain that high level of safety and that does take some ongoing work and maintenance for homeowners as well.

Our daily lives depend on the use of appliances, computers and communication devices for work, play and keeping everything coordinated and organised, so protecting these electrical gadgets and whitegoods is essential to keep us on track, and avoid unnecessary replacement and repair costs.

What is a Power Surge?

A power surge is a spike in the amount of electricity flowing into the wiring of one, or even multiple devices, causing them to overload with more electrical current than they were designed to handle.

Power surges can be caused by electrical use inside your home, which accounts for over half of household power surges, but they can also come from external forces as well, like when tree branches rub against power lines or if a storm snaps off a branch and sends it across the wires.

The extent of the surge can vary greatly, from as little as five or ten volts when you turn on a hairdryer to thousands of volts for a transformer that is struck by lightning.

Power Outlet

Causes of Power Surges

Power surges occur when the flow of electricity is interrupted and then suddenly starts again, causing an electrical spike to jolt through any unprotected devices and equipment. An internal power surge can also be caused if a device that is supposed to draw electricity out, pushes electricity back into the system instead.

The surges that occur internally are common and can be so small you won’t even notice them. Whenever your fridge or air conditioner motor kicks in or the washing machine shuts off, it diverts power to or from other devices and changes the current of electricity flowing in your home.

The other cause of internal power surges is international power plugs. In Australia main volts run at 240 volts and 50 Hz. This isn’t the case for every country, which can create problems when you connect electrical products designed for overseas in Australian power points without adequate surge protection.

Outside your home, factors such as small animals getting into transformers, lightning strikes or trees interfering with the power lines are the biggest causes of neighbourhood power surges.

Lightning striking transformers is a very rare occurrence but the damage from these is severe to homes that don’t have any protection to divert the excess electricity to the ground. 

Risks from Power Surges

Internal surges are typically smaller. The damage here is slight and may go completely unnoticed, but over time the heat damage builds up, a bit like rust on wiring and will shorten the life of your appliance and impact its ability to function well.

Any electrical equipment with a microprocessor is particularly vulnerable to the electrical spikes caused by power surges as the tiny digital components are so sensitive that even a spike as little as 10-volts can disrupt them. Microprocessors are found in just about every electrical device from TVs, computers and microwaves through to dishwashers, refrigerators and washing machines.

As well as the microprocessor, the heat from electrical spikes can cause damage to circuit boards and other internal device components. The damage is so slight you might not even notice a surge occurring but if the surges are frequent, the internal circuitry will gradually degrade until it eventually fails. 

While rare, big power surges that come from external sources like lightning strikes and tree branches, cause instant and intense damage as plastic and metal components are completely melted and warped. This is costly damage as it will affect every unprotected electrical item in your home. You stand to lose not just your valuable electronics and have to rewire your house, but there is a high fire danger that can result in your entire home being destroyed. 

Signs of Power Surges

While small surges might happen a hundred times a day in your home without your knowledge, it’s important to pay attention to little tip-offs and get a licensed electrician to take a look to make sure your home electricity is safe and behaving the way it’s supposed to.

Here are some tell-tale signs an electricity surge has affected your device or appliance:

  • The device has turned itself off
  • The surge protector or fuse has tripped
  • The device lights or display clock are flashing
  • You notice a slight burnt smell
  • Lights flicker or dim when a large appliance, like the refrigerator, kicks in.

It’s all too easy to simply reset your fuses and go back to what you were doing, but ignoring warning signs like tripped fuses can cost you a lot of time and money down the track.


Protection and Prevention

Power surges happen without warning and they are very quick. You don’t have time to react in that instant, you need to put systems in place to prevent future damage. 

You have a lot more control over your internal power surges than the external ones, but in every case, do as much as you can to protect your home and prevent surges from causing damage. Some are some ways you can protect your appliances and prevent power surges:

  • Unplug unused devices

Unplugging electrical items you are not using is easy and saves on your electricity bill.  

  • Upgrade your home wiring

Homes built prior to 1980 tend to have a lower tolerance for high electricity use, simply because most of the common appliances we use now weren’t so common then. Now our large-capacity fridge, entertainment system, dishwasher and computer equipment put pressure on the wiring and are fire risks as well as triggers for electrical surges.

If your fuses trip or blow frequently or your lights struggle when other electronics are one, it’s a sign that your home needs a wiring upgrade. Speak to a qualified, professional electrician about what needs to happen for your home to be safe and efficient.

  • Divert power from overloaded circuits

Newer homes may still have issues with overloaded circuits if there are two or more large appliances connected to the same circuit ( or multiple smaller appliances, like computers) all drawing power at the same time. 

If you are drawing too much power on one circuit on a regular basis (this typically happens in the kitchen) ask your electrician to install dedicated circuits for big units or well-used rooms to help disperse power usage.

This is especially useful for pool pumps and tumble dryers and can also give you access to off-peak rates with some power providers.

  • Look out for hazards

Notify your council about overhanging tree branches or trees that look too close to power lines. It helps to take pictures so they can see the potential for danger first-hand.

  • Install a surge protector

The best way to prevent electrical surges is to install surge protectors either by buying high-quality power boards that have cut off switches, or by having a licensed electrician assist with installing a quality surge suppressor (surge protector) which will ground any excess electricity safely.

Electrical surges of every intensity can affect multiple devices on a power circuit, not just the one device that is causing the surge, this includes phone lines as well. Electricity can travel and surge through phone lines as well as cable TV.

Having surge protection that covers all your devices and appliances is the only way to know for sure you will be protected from a power surge. 

  • Check your international device usage

If you do have international electronics make sure you have a high-quality adapter to convert the power to the right voltage when using Australian power points and provide surge protection. 

  • Unplug during blackouts

One situation you need to be especially careful of in your home is after a blackout period. There can be an intense surge when the power connection is reestablished with all home circuits trying to deliver power to outlets simultaneously.

If you have experienced a power outage after a storm or power cut, unplug all your electrical appliances and connect them one by one when your power service is resumed to obtain a steady and controlled flow of electricity.

  • Review your insurance policy

In some cases, you can make an insurance claim on appliances damaged by electrical surges through your home and contents insurance provider. Check your policy to see what you have covered and under what circumstances claims can be made.

Power surges occur when there is an electrical spike from internal or external power sources.  Even small spikes in electricity can cause a build-up of damage that reduces the life and functionality of common devices in your home, and large surges can wipe out your valuable electronics for good.

Prevention is the best method of protection when it comes to power surges. We urge you to pay attention to warning signs so you can get electrical issues taken care of before irreversible damage is done.

Make sure you are using quality adapters and power boards that have surge protection in place as cheap adapters and power boards offer zero protection from surges. You pay extra for the additional safety components the high-quality adapters and power boards include, which is worth the peace of mind. 

For genuine and long term fixes that cover your entire home, ask a qualified professional electrician to help upgrade overloaded circuits or old wiring in your home and install total surge protection devices to make your home as safe and efficient as possible.

Surge protection is a small yet solid investment for your electronics and appliances. Talk to our trusted team of qualified electricians at All Electrical Plus here in the Northern Beaches about what we can do to protect your home from internal and external power surges.

Your Local Sydney Electricians

Electricians Sydney Northern Beaches and North Shore
All Electrical Plus is a local electrical and solar installation business, providing home improvement services to the Northern Beaches and Northern Peninsula.


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