Surge Protectors 101

It had a rectangular body with a snake-like appendage that connected it to a plug on the wall. A number of helpless electrical devices plugged into the rectangular brick that was its power source. Its name was Surge Protector–the guardian of computers and electrical appliances, and preserver of operational voltaic doohickeys.

Surge protectors may not be one of the X-Men or Fantastic Four, but they’re definitely super heroes for any techie or techie-wanna-be. But what are they? Why are they so necessary? How do they work? And what kinds are the best?

What's a Surge Protector?

Surge protectors come in many different shapes and sizes, but they all have one thing in common: they all protect electrical devices (computers, monitors, printers, televisions, DVD players, CD players, etc.) from surges in voltage. That’s what surge protectors do. They're always on duty: during a lightning storm; freak voltage spikes from the power company; or—more likely than not—a surge in power from demands by high-power electrical appliances or devices, like air conditioners or vacuum cleaners.

Without a surge protector your electrical devices are helpless sitting ducks, waiting to be crisply blackened by the fire of unrestrained electricity. Besides preventing such an unpleasant scenario, surge protectors usually come with multiple plug-in receptacles, a welcome bonus for any PC owner.

How Does It Do That?

Okay. So surge protectors are both necessary and convenient. But how do they work? Well, when a power surge comes through the electrical wires in your home, the voltage increases. Increased voltage is a frightful thing for computers because they don’t have too much leeway before they're toasted. Thus, enter our super hero surge protector.

Your voltage spike comes through your wires to the surge protector en route to your computer. The excess voltage (which would have possibly destroyed your computer) is rerouted to the ground wire via what’s called a metal oxide varistor (MOV). Only the excess voltage is diverted through this screen of metal oxide; this is due to the material’s resistance to the rated voltage (typically 120 volts in North America).

Almost miraculously, the voltage level taken in by the computer isn't interrupted. All goes well. Your computer’s happy. You’re happy. Your surge protector‘s happy to have been a help in the background. Smiles are all around. This is how the standard surge protector works.

As with anything electrical, there are nearly a billion different styles of surge protectors. But the basic idea is to divert the excess voltage to the ground wire. Many surge protectors also supply a back up protection in the form of a built-in fuse.

Which One Should I Get?

I already have an inkling of what you’re wondering now: "Yeah, surge protectors sound like a good idea. But how much do they cost and what type or kind works best for me?"

Well, frankly, I don’t have the time or space to give an exhaustive compendium of surge protectors. So, suffice it to say, you’re going to have to do some homework. However, I'm such a nice, thoughtful, considerate guy that I’m willing to start you off and point you in the right direction!

Before we start, let me just say if you don’t have a surge protector guarding electrical devices such as computers, televisions, DVD players, surround sound systems—anything with intricate wiring systems—get one now! I'm surprised you've survived thus long without one. That being said, let’s get more specific.

  • Consider price. You can get cheaply priced surge protectors which are just as well cheap in quality. So, if you are looking to protect your multi-thousand dollar entertainment and/or computer system, don’t settle for the $5 one unless you know what you are doing.
  • Make sure it’s rated as a bona fide surge protector. Before you purchase a surge protector, look for the Underwriters Laboratories (UL) ratings (if it doesn’t have one, don’t even consider buying it). Make sure it is listed as a “transient voltage surge suppressor.” This guarantees the surge protector is indeed rated as such, and saves you from unknowingly “protecting” your state-of-the-line computer system with an untested piece of junk.
  • Don’t purchase a surge protector without an indicator light. This light will inform you when the MOVs have given up the ghost. And, as you know, a surge protector with dead MOVs is a dead surge protector.
  • Do your homework. There are many various types of surge protectors with billions of different options and ratings. Here are some tips when it comes to doing your homework. A better surge protector is one with:

    1. a lower rating of clamping voltage (preferably 330 V)
    2. a higher rating of energy absorption (try 700 joules and up)
    3. less of a delay time (think less than one nanosecond)

Now that you've received the basics, have fun searching for your electrical super hero, your device of steel, your surge protector!


Very helpful.  I certainly won't plug anything in without one.  Does a charger for a laptop protect against surge?

All surge protectors connected to a socket will still let threw voltage up to 330 volts or even more depending on the specifications of the surge power bar. Anything connected to a surge protector still uses 250%+ of the power requirement when there`s power surges.

They do not offer protection against surges for appliances and electronics not connected to a surge protector. All small electronics and appliances not connected into a surge protector suffers the effects of full power surges.

New technology high quality whole house surge suppressors can now clamp voltage at 130 volts. Improving life expectancy by up to 32% of all electronics including appliances, electronics with microprocessors and anything with a motor.

According to industry standards, power line surges inside a building can be up to 6,000 volts, and 3,000 amperes, and deliver up to 90 joules of energy. Including surges from external sources.

Any surge protector offering protection over those specifications is extra for nothing, a gimmick.

Typically destructive surges are hundreds of thousands of joules. Lightning and other high-energy transient voltage surges can only be suppressed with a whole house surge protector.

Surge protectors can offer no protection against indirect or direct lightning and other high-energy transient voltage surges.

Research and detailed information about power surges, surge protectors and lightning strikes can be found on this page:


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