Safeguarding the Connected Home

The typical home now has thousands of dollars worth of sensitive electronics. That makes adequate surge protection a must.

Today's homes are packed from floor to ceiling with sophisticated electronic equipment -- phones, faxes, computers, printers, VCRs, DVD players and big-screen TVs. Even everyday appliances such as ovens, washers, dryers and furnaces now include electronic circuits. All this equipment, which in high-end homes can cost tens or even hundreds of thousands of dollars, is perpetually at risk of damage from "transient voltages" -- power surges that can carry thousands of volts, more than enough to make toast of an electronic circuit. That's a good argument for installing surge protection. "The dollar volume of electronic equipment in the home is higher than ever, and people want to protect it," says Mike Connor, vice president of purchasing for the North Florida division of US Home. "If there were no fluctuations in electrical current, this equipment would last nearly forever, but as it is, even minor spikes unnecessarily wear it down."

Surges can shorten the life of a piece of electronic equipment by half, says Bruce Jackson, electrician and owner of Jackson Brothers Electric, a residential electrical-contracting firm based in St. Petersburg, Fla. "High-end equipment, because of its cost, complexity and greater sensitivity, of course, needs superior protection, but anything with a circuit board in it, right down to the toaster, is susceptible to surge damage today."

Surge Sources

Transient voltages can come from outside or inside the home. The most visible and dangerous source of outside surges is lightning, which can pack well over 100,000 volts per strike. The transients that lightning induces can travel miles in every direction. Power disruption due to aging facilities, electrical deregulation and grid switching also accounts for a growing number of outages. These assaults enter the home through power, phone and cable lines.

Within the home, most surges are caused by the motors on large appliances, which can draw 10 times their normal amount of current when starting up. "When big motors start, they cause powerline spikes that affect everything in their path," says Jackson. "Freezers, refrigerators and air conditioners, for example, will cycle all day long to maintain a set temperature, causing a spike each time they turn on. That repetitive pattern will wear down improperly protected electronic equipment, and eventually cause it to fail."

The problem is worsened by the fact that many of today's electronic circuits use very low voltages, making them especially vulnerable to damage. An RS-485 data circuit running at 3 volts, for example, may suffer damage from relatively small overvoltages. In contrast, the simpler analog components of previous decades might not have reacted until voltage reached 10 times normal.

Surges don't have to harm systems or components to cause problems. "The barrage of low-level surges coming into homes causes audio and video quality to deteriorate, even when equipment continues to operate," says J.B. Haviland of DITEK, a manufacturer of surge protection equipment in Largo, Fla.

"Homeowners will notice glitches, too: lights dimming or switching on and off by themselves when automated, VCRs flashing 12:00, or microwaves reading 'PF' for power failure."

The Protection Gap

While many electricians and electronics installers now specify surge suppression, many also don't provide enough of the right kind of protection to do the job. Some assume that manufacturers build protection into their products. Wrong: Some manufacturers are reportedly stripping out built-in surge suppression because it adds to cost.

Many homeowners, on the other hand, rely on plug-in power strips with surge suppressors. These are approved to withstand 6,000-volt surges, but they can't protect the electronics in hardwired appliances such as air conditioners and oven ranges; and they don't always have connections for phone or cable TV lines, from which roughly half of all surges enter the home. The typical power strip won't take repeat hits: One good spike could permanently damage it. And because it usually won't warn the homeowner of that damage, the next surge could fry the supposedly protected equipment. Needless to say, this can make homeowners very unhappy.

Since liability for cooked electronics can easily run between five and six figures in high-end homes, builders and their electricians owe it to themselves and their clients to get surge protection right. "The last thing I want to do as an electrical contractor is install inadequate surge equipment. That's why cascaded or staged surge protection is so important," says Jackson.

In a staged system, the first line of defense is a whole-house surge suppressor installed near the electrical service panel. This device has been likened to a pressure valve. It usually does nothing, but if a surge enters the house, the device "clamps" it, and shunts it to ground -- while still letting normal voltage reach the home's outlets. "The whole-house device acts like a suit of armor against the hostile outside world, taking the brunt of the hit so that only an acceptable level of energy reaches the home's circuits," says Haviland. Whole-house systems can range in price from $129 to $1,000. The more expensive ones are more durable: A good-quality system will reset itself and accept thousands of surges before self-sacrificing. They also have more features -- including buzzers that warn when the device has been damaged and plug-in modules that are easily replaced if damaged.

The second line of defense is a point-of-use suppressor, such as the familiar plug-in power strip.

"The trend is definitely toward whole-house surge protection, augmented by point-of-use protection," says Connor. "Approximately 75 percent of our home-owning customers in the North Florida area chose whole-home surge protection in 2001. Granted, we're in a high-lightning-risk zone, but beyond that, people understand that it's the smart thing to do if they want to protect their investment in electronics."

The best surge-protection system will depend on the size, features, location and equipment protected in any residence -- as well as the project budget. Here are points to consider when making the choice.

• Use a whole-house device designed from scratch to protect electric, phone and cable lines. Avoid cobbling together different systems for these purposes, especially if separate manufacturers make them. "Some companies make just the AC power surge protector, but not units for phone or cable lines," says Jackson. "If you use equipment from three different companies, the systems may not work together properly, and there will be finger-pointing if there's ever equipment loss."

• Use a system that clamps excess voltage from about 130 volts. Generally, the lower the clamping voltage, the better. Some suppressors don't clamp excess voltage on a 110-volt circuit until voltage reaches 220 or even 480 volts. By the time voltage reaches these levels, sensitive equipment could be seriously damaged.

• Look for an energy dissipation capacity of at least 25,000 amps in any given mode, and more than 125,000 amps total. The more energy the system can dissipate, the less damage there will be to homeowners' equipment.

• Use a system that is UL listed for power (UL1449) and telecom (UL497A). For the best protection, verify that the Suppressed Voltage Rating for power is 400 volts or lower.

• Use self-restoring surge protectors. These clamp the overvoltage, then automatically reset themselves to passive mode until the next surge. They can stop hundreds of surges. One-use devices, by contrast, offer no protection after a surge until they're replaced.

• Consider a system with "smart module" technology. For example, DITEK's StormShield has five modules. If the first takes a hit and is damaged, the other four will continue to protect the home's circuits. Meanwhile, the device will sound an alarm to tell the homeowner that the damaged module needs to be replaced. These modules are designed so that homeowners can easily change them: Just pull the bad module out, snap the new one into the base assembly, hit the reset buton, and the system is fully protected.

• Use surge suppressors that meet the latest electrical, fire and safety codes. Some manufacturers mass-produce or import products. Inventory that has been sitting in a warehouse may fail to meet the latest codes.

• Use a surge counter, which records the number and strength of surges. It's an effective way of both educating and reassuring homeowners on how important surge protection is. The better whole-house devices include these, and you can also get plug-in versions.

• In addition to a whole-house device, provide point-of-use protection for sensitive electronics.

• Don't be surprised at what homeowners will spend to protect their electronic equipment. A top-of-the-line whole-house suppressor could cost $1,000, plus installation, but that's not a lot when you consider the alternative. "When homeowners are spending from $20,000 to $50,000 and up on electronics and appliances, they're more than willing to spend a reasonable amount to protect their investment," says Haviland. "If the first time they hear about whole-house surge protection is after half their equipment is inoperable, they won't be happy."

Those same customers will see a contractor who understands whole-house surge protection as an important ally: Someone who will help keep their latest, greatest gadgets and appliances out of the junk bin.