Power Surge Protectors: What Are They and Do I Need One?

What is a surge protector?

A power surge protector is an electrical socket that sits between your wall socket and the plug on an appliance or device. By plugging the surge protector into your wall socket, and then your device into the surge protector, you protect the device from any power surges that occur.

Commonly, surge protectors come in the form of a multi-box/power board, but it’s important to note that not all power boards act as surge protectors.

What is a power surge?

Electricity flows like water from a tap at a standard pressure, measured in voltage. Here in NZ, our power supply runs at 230/240V, and electrical devices are designed to work to that level.

However, on some occasions, the voltage can fluctuate. When this happens, and there is a brief surge in the flow of electricity, it can overwhelm our appliances. And, depending on the size of the surge, it can damage them.

What happens during a power surge?

A power surge usually isn’t as dramatic as you’d expect. And your appliances aren’t likely to blow up in a frenzy of sparks and flames, although they can in the worst case scenario. Telltale signs of a surge include flickering lights, a reset electronic timer, a tripped switch on your circuit board, or you might notice a slight burning smell coming from a plug or electrical device.

However, a surge can cause a lot of damage in the home. A powerful surge can fry the electronic circuitry in devices and burn out electric motors. It can also affect the wiring in your walls.

What causes a power surge?

There are a few common causes for power surges:

Overloading power points

Multi-plug boxes have a set amount of voltage they can handle. For example, plug five appliances into a five-plug multi-box and you’ll be running about 1200V through it. If your multi-box can handle up to 1800V then you’re fine.

But some of us are guilty of plugging in four appliances and then using the fifth socket to load up another multi-box. Doing so is dangerous. Best case scenario your multi-box stops working. Worst case, it causes a fire.

Faulty wiring

Faulty wiring can be hard to detect, as it’s commonly hidden behind walls. However, burning smells or buzzing, flickering lights can all be signs. If so, unplug all appliances and contact an electrician.

The power turning back on

After a power outage, when power is restored, it can sometimes cause a power surge.

External surges

A variety of external factors can lead to a sudden surge in electricity flow. These include lightning (although not overly common), or the cause could be your power company. Whatever the reason, there may be occasions where the voltage flowing into your home surges above its normal range, damaging your appliances.

Minor internal surges

Simply turning appliances on and off can cause regular minor surges. And appliances with motors that turn off and on can cause surges, too. While not significant, repeated minor surges can wear out appliances and cause them to degrade over time.

 Compare electricity providers with Canstar Blue

Canstar Blue rates NZ power companies for customer satisfaction and value for money, see the table below for some of the results, or you can click on the button below for the full results of our survey.

Canstar Blue’s latest review of NZ power companies compares them on customer satisfaction. The table below is an abridged version of our full results, available here.

How do power surge protectors work?

Power surge protectors are a type of electrical socket. You plug your device(s) into the surge protector and then the surge protector into your wall socket. It’s also common for multi-plug boxes/strips to have power surge protection included, and it’s possible you may have one without even realising.

Surge protectors detect fluctuations in the electricity flow and redirect any surges to your home’s grounding wire. This avoids the surge from entering your appliances and damaging them.

However, it’s worth noting that these do not typically provide adequate protection from significant surges that can be caused by things such as lightning strikes.

Although we don’t suffer from an abundance of lightning strikes here in New Zealand, it’s typically recommended to unplug valuable electronics, such as computers, TVs and gaming consoles during severe storms.

How common are power surges? Do I really need surge protectors?

Power surges are actually extremely common. Though, they are typically small and internal. For example, turning on your heat pump can cause a small power surge.

However, small and repeated power surges can degrade devices and appliances over time. So, while they won’t blow up your computer, they could impact its shelf life. So it could be wise to use surge protectors on your most valuable and expensive appliances.

And if for some reason there’s a more significant surge, you can rest easy knowing that your most prized possessions will be safe.

Power surge protectors: a buying guide

If you are keen to grab yourself a surge protector, it’s important to know that they’re not all made the same. When looking for a surge protector be sure to check:

• Surge protection (joules) – this is the total amount of electricity your surge protector can redirect/suppress. Once this limit is reached, the surge protection will fail (though it will still function as a regular plug). A higher joules rating will mean the surge protector can either withstand a larger surge, or simply last longer
• Status light – indicates if the surge protector is operating or not
• Overload protection – if the load power exceeds a certain wattage, a reset safety switch will trip off automatically
• Number of sockets/USB ports – surge protectors can be a single socket or multiple sockets. Some even have USB ports included. Think about where you’ll be using it and how many devices you want to plug into it.

Do you need a surge protector when using overseas appliances?

Mains power here in NZ runs as 230/240V and 50Hz. Many countries, including the USA and Japan, have appliances that run at a different voltage (eg 110V 60Hz).

That means if you were to plug in certain devices from overseas, you could end up running a bunch too much electricity into it, which could break the appliance. However, a surge protector is not going to help here.

As mentioned above, surge protectors can help prevent the electricity flow from surging above normal. But if the appliance is only built to handle 110V, then even the ‘normal’ voltage here in New Zealand will be too much.

Fortunately, most modern appliances are dual voltage and come with a voltage range that can handle most countries. So you shouldn’t have to worry about plugging your laptop in wherever in the world you are. But always be sure to check the label on your appliance or packaging. If it’s dual voltage, it will typically say a large voltage range separated with a slash – such as 100/240V.

Certain appliances, however, are not dual voltage. If so, you won’t be able to use it without a voltage converter/transformer. While not particularly expensive, they can be bulky so aren’t necessarily ideal for travel, but can be helpful when using certain imported appliances.

Compare Electricity Providers

About the author of this page

This report was written by Canstar Content Producer, Andrew Broadley. Andrew is an experienced writer with a wide range of industry experience. Starting out, he cut his teeth working as a writer for print and online magazines, and he has worked in both journalism and editorial roles. His content has covered lifestyle and culture, marketing and, more recently, finance for Canstar.