How Does A Surge Protector Work?


I love watching that TV show, “How Its Made.” Seeing how things are made is cool right? So, I thought I’d write a post about, What Does A Surge Protector Do? I researched and put everything together to shed some light on the scene. I love exploring this type of stuff and discussing. If you do too, read on.


A surge protector is a device designed to protect your property against voltage spikes aka power surges. When voltage spikes occur, the surge protector limits the voltage throughout your electrical system to prevent damage from occurring to things within your system, such as your computer, electronics, and other appliances.

How Does A Surge Protector Limit The Voltage?

By blocking or shorting to ground any unsafe voltages, the surge protector can maintain a safe voltage within your electrical system when power surges occur. If you don’t have a surge protector, voltage spikes can fry your electronics in a flash. Your air conditioner and refrigerator may stop working a few days later for no apparent reason, and what’s worse is that it’s VERY hard to prove that they died due to a power surge. So having those insurance policies that cover power surges, good luck filing a claim and actually winning.

You’ve heard the old adage: “Prevention Is Key” right? Well, shielding your home or business from voltage spikes is a no brainer on this one. But, what happens when your lights flicker for a few seconds? What should you do? This is called a brownout and occurs when the power grid isn’t supplying enough voltage to your system.

What is a Brownout?

flickering-lightA brownout is the opposite of a power surge. When voltage gets too low, this is a brownout. Whether intentional, such as an intentional load reduction in an emergency (to prevent a complete grid blackout in your town), or unintentional like a large facility powering on a large motor and drawing down the power grid, brownouts are not good.

Brownout refers to the color of the bulbs dimming when the voltage drops. Brownouts can last anywhere from a few seconds to a few hours depending on what’s causing it. Usually the first sign of a brownout is the lights dimming.

What Should You Do First In A Brownout?

When a brownout occurs, the first thing you should do is save anything you are currently working on in your computer and power it down. Then focus on turning off your Air Conditioner, TV, Electronics, washer, dryer, and other large appliances… yes even your vacuum. This is to prevent that brownout on the power grid from becoming a complete blackout. It’s also to protect all those things that you don’t want to be fried and have to start replacing in the next few days.

While blackouts are rare (depending on where you live of course), they are always a possibility. So powering down anything that you don’t want to replace is a good idea.

Why are Brownouts Bad?

Computers and other valuable electronic devices are sensitive. The irregular voltage can and will damage them fast. In the case of a brownout, power down all your electronics and unplug them. This will prevent them from receiving any low voltage to them and destroying them. Surge protectors won’t protect your electronics in a brown out (or low voltage situation). But, as the electricity starts powering back up, it’s common to see a power surge directly after a brownout. So having some sort of surge protection on your property is important.

This is where power strips are very handy. In a brownout, (if you are lucky enough to be home when it occurs) You can easily flip the switch and turn off all power to all the electronics plugged into the power strip. If the power comes back surging, your power strip will be ready to take the heat!

is-it-real-surge-protectorAre All Power Strips Surge Protectors?

Short answer is no. How much protection do you want to provide for your home? This depends on what you have in your home that needs protection. Most surge protectors are rated in Joules of protection, click here to read more on that. If you have a computer, home stereo or entertainment system or multiple electronics and appliances, having whole house surge protection is strongly recommended- Watch this video below on why:

For Your Computer:

An Uninterruptible Power Supply (aka UPS) for your computer. If a brownout occurs, this will give you the time to save your work and power down without losing power. I also recommend behind that having your UPS connected to a power strip (to protect against power surges) which then would plug into the wall. Most power strips with surge protection built into them only protect against a surge 1 time and then you need to replace the power strip. But, that’s way better than replacing your entire computer system right? I’ll take a $20 hit over a $2000 hit any day of the week.

For Your TV & Electronics:

If you have a home entertainment system or other electronics that need protection, a power strip is the very basic minimum you should have plugged in between it and the outlet. I recommend also to protect your system with a dedicated surge protector or as a basic minimum at least a power strip for this. And if you have both a home entertainment system as well as other electronics in the home, you should definitely look at protecting your entire home in addition to what I recommended above.

For your Home:

When needing to protect your entire home against spikes and voltage drops, the best thing to do is to have a whole house surge protector installed on your electrical system. This will protect all your motors, appliances, and electronics in your home from getting zapped & fried unexpectedly.

Most Central A/C and Refrigerators have some sort of small surge protection built into them already. However, most of the time it’s only enough to handle a slight surge or lag in your electrical system, not a full on voltage spike, so they are not enough to truly protect your systems.

Will A Surge Protector Or Power Strip Protect Against A Lightning Strike?


When a thunderstorm occurs, lightning is usually right there too. If lightning strikes nearby, this can definitely cause a large power surge on the grid and right on into your home. By having a whole house surge protector installed on your electrical panel, this is the 1st step at shielding your home and making a big difference. If you have a power strip plugged into your wall outlet and your TV and DVD player plugged into the power strip and a surge comes down the line, usually the power strip will protect it. And then, unfortunately, you will need to go out and buy a replacement power strip. It’s function is to sacrifice itself to protect the electronics plugged into it.

However, if your property is hit directly by lightning, nothing on planet earth can save it. That’s just an unfortunate fact. Because there is so much voltage in that lightning bolt, there is just no way to filter or block it completely.

I’ve seen a direct lightning hit on a cable box that wasn’t grounded properly. This led to several things in the home being completely fried. All because proper grounding wasn’t done. So, always be sure everything in your home is properly grounded. And when dealing with electricity, remember it is dangerous. Always hire a licensed professional to ensure your home’s electrical system is in good shape BEFORE trouble strikes.

In Summary

Power Strips, Surge Protectors, UPS’s, and Whole House Surge Protectors all have their place in your home and business. It simply depends on your particular needs. You may need only 1 of each or several of each. In my office, I needed several as we have computers/printers & electronics there. But for my home, several power strips and a whole house surge protector did just fine.

You know what they say, Hindsight is 20/20. I don’t know about you, but I’d rather be protected against power surges than have to pay the ultimate price of replacing all my electronics when I least expect it. Having to spend your vacation fund on a new A/C unit or TV sucks right?


>> What Causes Power Surges? <<

>>How Many Joules Do I Need?<<