Every year, we add to our homes more electronics that are vulnerable to power surges. You probably added another device this Christmas. Some of the devices I am talking about are computers, the circuit boards in your refrigerator, oven, microwave, dimmer switches, your TV, DVD player, garage door opener, and the GFI outlets (Ground Fault Interrupt outlets in your bathroom and kitchen). The repair bill for a single surge on an unprotected house can exceed $10,000.
There are two types of surges that can damage your electronics. The most feared are lightning-induced surges. They are the largest, but in fact, most surge-related damage is not caused by lightning. Far more common, if not as dramatic, are surges caused by downed power lines, transformer failures, sudden changes in electricity use by a nearby factory, or even the cycling on and off of motor driven devices in your home, such as air conditioners, refrigerators, electric dryers, and even laser printers.
There are also two types of protection, and you should have both of them. The first is a whole-house suppressor that is hard-wired to the service panel and can eliminate the big, dangerous power spikes. A licensed electrician can install one in about two hours at a total cost of about $500. Whole-house systems should be rated to stop a 40,000-amp surge, at minimum. Features to look for include thermal fuses and lights or alarms that indicate when a device has taken a hit.
By themselves, whole-house suppressors canāt stop surges completely; up to 15 percent of excess voltage may leak by. Thatās where āplug-inā surge protectors come in. Individual circuit or āplug-inā surge suppressors need to be installed for vulnerable appliances and electronic devices such as computers, televisions, and audio-visual electronics. Many people have multi-outlet extension cords with an on-off switch to plug in their computers and monitors. You should examine the specifications, but if you paid less than fifteen dollars for your cord, it does not contain a sufficient surge protector to protect your electronics. Without getting into a very technical discussion of metal oxide varistors (MOV), understanding the capacity of a surge protector is difficult. The bottom line is that for your computer, you should have a surge protector of 480 joules or more. The APC net7 at about $20 is a good example of this device. For your flat screen TV and audio-video electronics, you should look for a surge protector of 1000 joules or more.
You should also avoid plugging surge-sensitive electronic devices into the same power strip with laser printers, air conditioners, or other appliances with large motor loads. These produce their own low-level power surges that will affect all the devices sharing the strip.
Both types essentially act like pressure-relief valves. Normally they just sit there, allowing electric current to flow through them. But with higher-than-normal voltage, the devices instantly divert excess voltage to the ground wire. (The best ones react in less than a nanosecond.) As soon as voltage levels return to normal, the flow of electricity is restored, unless the surge was big enough to melt the fuse built into some units.
Surge protection is something many homeowners donāt think about until a power surge wipes out the electronics in their flat screen TV, computer, garage door opener, or microwave. It is something you should consider adding to your home.
*Note from Sun Day owners, Chris and Erika La Pelusa: A few years ago, we had lightning strike our condo building and āblow outā our TIVO system (and nearly electrocute our dog, who was cowering in the corner near the outlet the TV/TIVO was plugged into). It was quite a spectacle to behold, as it was a mini purple-blue-white explosion from the outlet. The damage to the TIVO was such that it could only work if hooked up to cable directly, which thankfully saved us the cost of a new one. But power surges and the damage they can cause to electronics, we learned, are very real things that can occur when you least expect it, and we now have appropriate surge protection on the electronics that require it.
If you have suggestions for future tips or have questions about maintenance around your home, submit them to ask.the.woodchucks@gmail.com.
