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Practical Computer Advice
from Martin Kadansky

Volume 8 Issue 7
July 2014
The Top Two Things You Should Know About Surge Suppressors

It's down there on the floor near your computer, under the disturbingly necessary quantity (and tangle) of wires and dust that comes with having so much technology in our lives, but is your surge suppressor really doing a good job protecting your equipment? You might be surprised to learn that it's not!

What should you look for when buying a surge suppressor for your computer?
When buying a consumer-level surge suppressor for a computer (or other device worth protecting), the designation UL 1449 is the most important thing to look for. This a standard defined by Underwriters Laboratories for the minimum acceptable performance of surge suppressors. If you're at a retail store, you should see "UL 1449" on the product box and on the unit itself. If you're shopping online, remember that product descriptions vary widely, so even if the item meets the UL 1449 standard, the description might not mention that. If it's unclear, try asking the store or seller, or move on to another product or store that does specifically list it.

And, if your current surge suppressor does not specifically list UL 1449 as one of the standards it meets, I strongly suggest you replace it right away with one that does.

When should you replace your surge suppressor?
If you experience a big and noticeable power surge, you should replace your surge suppressor immediately since it has probably given its life to protect your equipment. Otherwise, over time your surge suppressor will likely absorb a large number of small surges that you may never notice. These can be caused by fluctuations in the quality of the power coming into your home or office, or by small surges that occur when big appliances like refrigerators or air conditioners or elevators start up.

These small surges will probably slowly erode your surge suppressor's ability to protect your equipment if a big surge does occur, especially if it's built with MOVs (Metal Oxide Varistors), which are "sacrificial devices" that absorb excess electrical energy and dissipate it as heat. The most prudent advice I've received from experienced hardware technicians is this: Plan on replacing your surge suppressor after it has been in service for 3 or 4 years.

Here's how I implement this: When I set up a new surge suppressor for a client (or myself), I take today's date and add 4 years, and then label it "Replace me in (month & year)." For example, if I were setting one up today, since it's July 2014, I would write "Replace me in July 2018."

And, if you can't remember when you bought the surge suppressor you're currently using, it's probably already worn down, so I strongly suggest you replace it right away.

That's it. You now know the two most important things about surge suppressors. You can stop here if that's all you want, or read on for my additional advice.

Don't just focus on surges on power lines
Most consumer-level surge suppressors protect against surges on power lines. However, it's also important to look at all the wires through which a power surge could damage your equipment, including your telephone wiring, internet connection, cable or satellite wires, etc. Many consumer surge suppressors also include protection for phone/fax lines and coaxial cables.

What is a surge suppressor?
A surge suppressor does 3 basic things:
  • It detects power coming over a wire that's above an acceptable level.
  • It absorbs and redirects that excess power to ground to protect your equipment.
  • It does this extremely fast.
Additional considerations
You should also keep the following in mind:
  • Terminology: The terms "surge suppressor" and "surge protector" are interchangeable, but "power strip" implies very little protection, usually just a fuse to prevent fire. Just because it has multiple outlets doesn't make it a surge suppressor!
  • Grounding: A surge suppressor can't protect your equipment if it isn't grounded. Make sure the wall outlet you plug it into is properly grounded. You can buy an "outlet tester" or "electrical receptacle ground tester" or "3-wire receptacle tester" to check this for a few dollars. It's a small 3-prong plastic device that, when plugged into a wall outlet, will light up to tell you immediately whether that outlet is properly wired and grounded.
  • Cost: As long as it complies with UL 1449, I don't know of any good reason to spend more for one surge suppressor over another, unless the unit significantly exceeds that standard and this fact gives you better peace of mind. At the time of this writing, I easily found compliant surge suppressors (which also have 12 outlets, phone/fax and coax protection) on amazon.com for under $25.
  • Beyond your computer: You should also buy surge suppressors for your other valuable electronics, including DSL and cable modems, wireless routers, printers, hubs, expensive TVs, stereos, phones, etc. Replacing a $25 surge suppressor after a surge is far better than having to replace a $1,000 TV.
  • Warranty: Many surge suppressors have impressive-sounding limited warranties that "cover" $10,000 or $100,000 or more in equipment losses for "connected equipment." Here's the catch: Most manufacturers reserve the right to inspect your damaged equipment, so you will probably have to ship it to them at your expense before they will even consider your claim. This is often completely impractical, not only for a computer (which might still contain valuable and confidential data), but also for other bulky or expensive equipment like monitors, printers, TVs, stereos, etc. For these reasons, I don't consider any surge suppressor's warranty to be a valid justification for a higher price.
  • Lightning: Don't let anyone tell you that a surge suppressor will protect your equipment from lightning. It's possible, but not likely. Unlike regular surges, which travel through wires to get to your equipment, lightning can also travel through the air and randomly destroy some devices (including battery-powered ones with no wires) but not others. Lightning can also hit the ground outside your home or office, travel up your ground wire, and then destroy your equipment that way. Protecting against lightning is complicated, expensive, and imperfect.
  • Unplugging: Some people like to unplug their equipment to protect it from surges when not in use. While this does isolate that equipment from regular surges through wires, it offers only partial protection from lightning. Installing a lightning rod or moving the equipment into a "Faraday cage" are better (but more complicated) options.
  • Power failure: Surge suppressors don't help when the power fails (except for protecting against any related surges right before the outage). For that you should consider getting an Uninterruptible Power Supply (UPS), which combines a surge suppressor with a big battery.
Where to go from here
How to contact me:
email: martin@kadansky.com
phone: (617) 484-6657
web: http://www.kadansky.com

On a regular basis I write about real issues faced by typical computer users. To subscribe to this newsletter, please send an email to martin@kadansky.com and I'll add you to the list, or visit http://www.kadansky.com/newsletter

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I love helping people learn how to use their computers better! Like a "computer driving instructor," I work 1-on-1 with small business owners and individuals to help them find a more productive and successful relationship with their computers and other high-tech gadgets.

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