As you invest in home electronics and smart home technology, it’s important to protect them from power surges that could cause damage. An electrical surge, a spike in electrical voltage beyond designated electric current levels, may be caused by power outages, lightning strikes, short circuits and tripped circuit breakers. While a power surge could damage your home electronics, there are a number of surge protection steps you can take to keep your devices safe.
The risk of a power surge and how to protect your devices
Generally, the standard voltage for most office and household wiring is 120 volts. Sometimes, double breakers at home are 240 volts. Either way, if the voltage rises above the appropriate level, it could damage your home appliances and devices’ electrical materials.
In instances where the surge is too high, electronic devices, as well as wires, may experience wear and tear from burning wires and strain. A large enough surge can destroy them. For this reason, it’s advisable to use surge protectors. Surge protectors are designed to not only detect the excess voltage but also divert the excess electric current to the grounding wire. Therefore, surge protectors should be used at all times, especially for expensive devices with intricate microprocessors such as televisions, computers, stereo systems, high-tech kitchen appliances and cell phones.
Additionally, surge protectors can be handy in reducing cable clutter while improving your electronic device organization.
The difference between a power strip and surge protector
A surge protector shouldn’t be confused with a power strip.
A power strip allows multiple electronic devices to be plugged into the power source. Power strips are particularly useful where you don’t have enough outlets to charge or use more than two devices at the same time.
On the other hand, the surge protector mainly protects electronic devices from a power spike or a momentary increase in power. Even though you can plug multiple devices into a surge protector to use and charge them at the same time instead of overusing an outlet, its main job is to send unwanted current to a ground wire instead of allowing extra current to potentially damage your devices.
Even then, some people assume that the power strip serves the same function as the surge protector.
How does a surge protector work?
A surge protector has a main power line that is also referred to as a live wire or hot wire. In addition, it uses an extra connection link the main line to the ground wire, which is commonly referred to as the earth wire. The earth wire is also the protective wire in the electric circuit responsible for sending unwanted current into the earth safely.
The surge connection is usually inactive and only becomes functional when there is a larger than normal voltage detected. This current is then diverted to the ground safely through the earth wire.
So, how does the surge protector determine when to divert the current? It uses a voltage-dependent resistor that is also known as a varistor. The varistor is made using a metal-oxide semiconductor that is a bad conductor of electricity.
In the event of excessive voltage, the semiconductor within the varistor becomes a good conductor of electricity and it starts to conduct electricity normally. This semiconductor continues to channel the harmful electric current into the ground for the entire surge period. When the flow of electric current is restored to normal levels, the semiconductor assumes its role of being a bad semiconductor once again. Ultimately, your electrical devices are not only protected during the surge but also when the power supply is stable.
Factors to consider when choosing your surge protector
- Clamping voltage – This is the measure of voltage prompting the surge protector to redirect excess electricity from the devices that are plugged. Lower is better for clamping voltage. Look for a trigger voltage of 400 volts or less.
- Joule rating – This refers to the maximum amount of energy that can be absorbed by the protector. The higher the rating the better. You’ll probably want a joule absorption rating of 700 or more.
- Response time – This is the length of time it takes for a surge protector to detect a possible surge hence a lower response time is better as it means a faster response.
- Warranty – If your surge protector doesn’t work the way it should, you want to know what’s covered, what isn’t and if you can file a claim if it fails.
How to tell if a surge protector is bad
No matter what kind of surge protector you buy for device protection, remember that surge protectors wear down. There’s no surefire way to know if your surge protector is bad, but some come with warning lights that indicate you need to get a new surge protector.
Since a surge protector’s job is to absorb additional energy instead of passing spikes of current to your valuable electronics, it absorbs electrical damage over time. Over time, the varistor degrades, which means its ability to redirect surplus voltage decreases.
Surge protector lifetimes are measured in joules, so the more joules your protector has absorbed, the more it has degraded. Many people recommend you buy a new surge protector every two years, but it depends on how many surges you experience at home.
Why surge protectors are not the only electrical protection you might need
A common misconception about surge protectors is that they will fully protect your electronics from excess power. But whether your surge protector is bad and you didn’t know or a surge is just too big, surge protectors may fail to protect your equipment from a sudden increase in electrical current.
Therefore, the best way to protect your electronics from irreparable damage is by unplugging your devices, especially in the wake of a storm. Devices that require a lot of energy to switch compressors and motors on and off are especially vulnerable to surges.
Surge protectors play an important role in protecting your valuable electronics from damage. However, employing multiple strategies to protect your electronics and appliances will help you save money and enjoy using your valuables for years.
Originally published 2/3/16. Last updated 1/17/19.