“Most homeowners believe that proper surge protection means plugging their television, computer or other electronics into a power strip. Unfortunately, that’s just not true.”
First, not all point of use surge protectors (power strips) are created equal. Second, a surge can follow any wire into your house — electrical service entrance wires as well as cable and phone lines. These surges threaten televisions, fax and answering machines, computers, modems, satellite systems, stereo equipment, DVR’s, etc. Third, delicate electronic circuitry is even in our modern appliances, leaving them as vulnerable as everything listed above, to the effects of surges.
Types of Surges:
A power surge may last for only a few millionths of a second, at its worst, it carries tens of thousands of volts, enough to destroy circuit boards, hard drives, appliances and home-entertainment systems.
Power surges caused by lightning are the most powerful and most destructive: “A 200,000-amp jolt crashing through a power line will burn standard 20-amp wiring like a light bulb filament.” Lightning can strike up to a mile away from your house and still cause major damage. A common misconception is that most surge-related damage is caused by lightning.
Far more common, are power surges caused by downed power lines, sudden changes in electricity use on your grid, or even the cycling on and off of laser printers, electric dryers, air conditioners, refrigerators, and other devices in the home. The damage inflicted by these minor power fluctuations can be instantaneous, but may not show up for some time. These type of surges can reduce the life expectancy of your electronics and appliances by half.
The Most Effective Defense:
The most effective defense against power surges is a two-pronged approach:
- A whole-house surge protector to protect against the big, dangerous power spikes
- “Point of use” (plug-in power strip surge protectors) for vulnerable appliances and electronic devices.
Under normal operation both surge protections will allow electric current to flow through them. When higher-than-normal voltage is detected by the surge protection equipment they instantly divert excess voltage to the grounding system. (The best ones react in less than a millisecond!)
When voltage levels return to normal, the flow of electricity is restored, unless the surge was big enough to damage the surge protector itself.
Typically, Whole House Surge Protectors are wired directly into the service panel, a process that any licensed electrician should be able to handle in very little time, typically no more than an hour or so. Whole house systems should be rated to stop a 40,000-amp surge, at a minimum.
Some features to look for include:
- Lights or alarms that indicate when a device has taken a hit
- “Joules” rating above 560
- Protection on all incoming lines (Hot to Neutral, Hot to Ground, Neutral to Ground) are the best.
- Be sure that you have connected device warranty from the manufacture.
Separate but smaller whole-house units are recommended for the phone and cable lines. A surge can enter your equipment via these wires as well as your by power lines. By themselves, whole-house surge protectors can’t stop all surges completely; up to 15 percent of excess voltage may leak by. That’s where “point of use” surge protection comes in. These additional buffers between individual electronics/appliances and wall outlets come in a wide variety of options and prices. They range from $20 units-$500 units.
Most plug-in models fall into three basic categories:
1) the familiar multi-outlet power strip
2) the multi-tasking surge station that has inputs for phone and cable wires as well as power cords
3) UPS (uninterruptible power supply) which cleanses electric power of random fluctuations and provides a short-term battery-backup in case power is lost entirely.
Point of Use Protection:
Before buying a point of use unit, check that it does the following:
- Meets UL Standard 1449
- Has a clamping voltage of 400 volts or less (the lower the number, the better the protection)
- A Joule rating of least 560
- Protects all three incoming lines: hot, neutral, and ground (Look for “L-N, L-G, N-G” (line to neutral, line to ground, neutral to ground) on the product’s spec sheet
- Will not function when it’s circuits are damaged by a surge
Even the best surge protector can’t do it’s job if the house wiring isn’t properly grounded; there has to be a single path for the diverted electricity to go ground. You should have your electrician inspect your grounding system to insure that it meets code and has been installed properly. Also, avoid plugging surge-sensitive electronic devices into the same power strip with laser printers, air conditioners, or any appliances with a large motor load. These produce their own low-level power surges that will affect all the devices sharing the strip.
Our homes are filled on average with $25,000 dollars worth of delicate electronics and appliances. The bottom line is, when you compare the cost of having this equipment installed in your home vs. the protection it provides, it really is an easy decision.
As always, you should have a qualified, licensed electrician evaluate and install your surge protection.