What You Need To Know About Surge Protectors

May 14, 2019, 6:33 PM | Updated: Feb 7, 2023, 11:18 am

SALT LAKE CITY, Utah – We often link lightning strikes to power surges, but they’re not the only cause. A mishap by the power company during maintenance, or even an A/C unit or refrigerator motor can create a damaging spike in power. Surge protectors are an inexpensive way to protect your electronics from getting fried by random surges. But, they are not all the same.

“If it doesn’t say surge protector on it, it’s probably not a surge protector,” said electrical engineer John Palmer, an associate professor at the University of Utah’s Electrical and Computer Engineering department.

Palmer says many people are actually buying power strips instead of surge protectors. They look very similar and they are often sold side-by-side.

Power strips and surge protectors are often sold side-by-side and look very similar, but only the protector will guard your gear against surges.

Power strips and surge protectors are often sold side-by-side and look very similar, but only the protector will guard your gear against surges.

“All too many of us just go in and look. We see something that looks like what we want with a low price and that’s what we grab,” Palmer said. “But, the difference between them is worth taking a minute or two to read labels and understand what it is we are purchasing.”

A power strip is essentially an extension cord with additional outlets. It offers no extra protection against a spike in voltage. But a surge protector can handle that random surge in power.

“It has an added feature such that when the power system has a voltage surge on it, or a momentary increase in voltage, it limits the energy transfer so that the surge doesn’t get into your high-end electronics,” Palmer explained.

Surge protectors are rated in Joules. That tells you how strong of a punch of extra electricity it can take. The higher the number of Joules, the bigger the surge a protector can absorb.

Electrical engineer John Palmer explains why the terms ‘power strip’ and ‘surge protector” are not interchangeable.

Electrical engineer John Palmer explains why the terms ‘power strip’ and ‘surge protector” are not interchangeable.

Below a thousand Joules works great for electronics like small appliances, cell phones and battery chargers. Experts recommend at least 2,000 Joules for more expensive and sensitive electronics.

“If I’ve got a high-end stereo system that’s, you now, worth several thousand (dollars) or more, then I want to invest in a more expensive (protector) and higher Joule rating,” Palmer elaborated. “Some of the higher-end surge protectors will have as many as 5,000 Joules.”

Another thing to consider besides Joules is the protector’s clamping voltage. That is the threshold of excess voltage it takes for the protection components to go into action.

“The clamping voltage is the absolute maximum that the device will ever allow,” explained Palmer. “In general, that’s only going to be when you have the very worst surges. Usually, it (the surge protector) will hold the voltage down to less than that clamping voltage.” The lower the voltage, the better.

Also, look for the protector’s response time. Usually listed as nanoseconds, this rating shows how quickly it reacts to excess voltage. Here again, the lower the number the better the protection.

Power strips and surge protectors are often sold side-by-side and look very similar, but only the protector will guard your gear against surges. Electrical engineer John Palmer shows how a surge protector and power strip differ on the inside. Be sure to look over the label to make sure you are purchasing the right device for your electronics.

“When you have, for example, a lightning strike that may happen in your neighborhood, this pulse voltage comes in. It can be very high, but it’s a very short duration,” explained Palmer. “So, if you don’t have a good response time on your surge protector, then the initial part of that surge my actually make it through your device (surge protector) before it responds and pulls that voltage down.”

Palmer also recommended buying protectors with more outlets than you need. You should never plug a power strip or another protector into an existing protector, to get more outlets. Not only will it likely void the manufacturer’s warranty on the protector, but it could spark an electrical fire.

KSL 5 TV Live


This photo provided by RR Auction shows a watch melted during the Aug.6, 1945 bombing of Hiroshima....

Steve LeBlanc, Associated Press

A watch that melted during the atomic blast over Hiroshima, Japan, sells for more than $31,000

A watch melted during the Aug. 6, 1945, bombing of Hiroshima, Japan, sold at auction Thursday for more than $31,000.

23 hours ago

(Photo by Tomohiro Ohsumi/Getty Images)...

Associated Press

Toyota recalls 280,000 pickups and SUVs because transmissions can deliver power even when in neutral

The recall is to fix a transmission problem that can let the vehicles creep forward while in neutral.

3 days ago

A sunset spectacle featuring two mitten-shaped rock formations crosses Monument Valley Tribal Park ...

Michael Phillis, Associated Press

Native American tribes gain new authority to stop unwanted hydropower projects

The U.S. Federal Energy Regulatory Commission has rejected several proposed hydropower projects on the largest Native American reservation in the U.S. The commission has also created a policy that essentially gives tribes early veto power over such projects.

3 days ago

New Jersey Devils goaltender Akira Schmid, front left, makes a save in front of New York Rangers ri...

Lindsay Aerts

Bill to raise SLC tax for NHL stadium funding advances, SLC leaders supportive

Over the last two days the Utah legislature has unveiled two major plans to help finance major league sports stadiums. On Thursday a Senate committee advanced the plan to fund the National Hockey League stadium and a “sports and entertainment” district downtown, which includes a sales tax increase of up to .5% in Salt Lake City.

4 days ago

Henry Barlow inside his cattle processing plant...

Alex Cabrero

‘We are going to feed American beef to the Americans’: Meat packing plant to open in Richfield

A new cattle processing plant in central Utah is expected to improve the state's food supply chain.

4 days ago

Matt Gephardt, journalists, looks as paper with a woman...

Matt Gephardt and Cimaron Neugebauer

Get Gephardt: Ticketmaster seizes back purchased seats

Imagine buying tickets to a show, then having the seller refuse to give them to you. That’s what happened to a Utah woman, when she got a refund she didn’t ask for.

5 days ago

Sponsored Articles

Modern chandelier hanging from a white slanted ceiling with windows in the backgruond...

Lighting Design

Light Up Your Home With These Top Lighting Trends for 2024

Check out the latest lighting design trends for 2024 and tips on how you can incorporate them into your home.

Technician woman fixing hardware of desktop computer. Close up....

PC Laptops

Tips for Hassle-Free Computer Repairs

Experiencing a glitch in your computer can be frustrating, but with these tips you can have your computer repaired without the stress.

Close up of finger on keyboard button with number 11 logo...

PC Laptops

7 Reasons Why You Should Upgrade Your Laptop to Windows 11

Explore the benefits of upgrading to Windows 11 for a smoother, more secure, and feature-packed computing experience.

Stylish room interior with beautiful Christmas tree and decorative fireplace...

Lighting Design

Create a Festive Home with Our Easy-to-Follow Holiday Prep Guide

Get ready for festive celebrations! Discover expert tips to prepare your home for the holidays, creating a warm and welcoming atmosphere for unforgettable moments.

Battery low message on mobile device screen. Internet and technology concept...

PC Laptops

9 Tips to Get More Power Out of Your Laptop Battery

Get more power out of your laptop battery and help it last longer by implementing some of these tips from our guide.

Users display warnings about the use of artificial intelligence (AI), access to malicious software ...

Les Olson

How to Stay Safe from Cybersecurity Threats

Read our tips for reading for how to respond to rising cybersecurity threats in 2023 and beyond to keep yourself and your company safe.

What You Need To Know About Surge Protectors