Power-Line Play

July 1, 2006
New residential lighting-control systems rely on power-line carrier technology.

Home automation began with lighting control. Basic on/off and dimming functions, as well as extensive preset lighting scenes activated by a single touch on a keypad, can be automated by using any home-controls protocol, either alone or integrated with additional automated systems, such as security and temperature control. For new single-family home construction and retrofits, one way to implement a lighting-control system is to use standard household power wiring to communicate commands — reducing construction costs and eliminating the need for special wiring or cabling.

“For lighting, anything that's connected to the power line is a very good medium for getting a low data-rate signal across,” says Jay McClellan, president of New Orleans-based Home Automation Inc. and chairman of the Consumer Electronics Association's TechHome Division. “They really install the exact same way. Using the existing wiring, you take out the old light switch, and you put in the new. It's very easy to do.”

Sometimes radio-frequency (RF) and infrared (IR) controllers may be used with these power line protocols to allow optional bells and whistles in the lighting system, such as remote-control access and motion sensing. Considering their particular skill sets and knowledge of household wiring, electricians should look into installing these types of systems as part of their business. “It may seem like voodoo to most electricians, but they already have a leg up on this industry because they understand the electrical infrastructure and how to make changes to accommodate this new technology,” says Steve Lee, former electrician and president of Northridge, Calif.-based Top Hat Automation. “Guys who aren't electricians and who are trying to put these things in are going to have a harder time. It's really suited to electricians to go in and be able to incorporate this into their business.”

The wheel

For three decades, the X-10 protocol has been the standard for single-family home-lighting control. “Basically, if you wanted to create the ability to turn all the lights on or off in the house with the touch of a button, X-10 was the only way to do it,” Lee says. “It's been around for years. Nobody jumped into the market to try and reinvent the wheel. It was what it was.”

X-10 systems send commands to individual devices over a fixed carrier frequency. A PC or touch pad may be used as the central-control unit, which sends signals — 4V maximum — to dimmers, switches and receptacles, which act as receivers, that have been installed throughout the home to provide automatic on/off and dimming and to create lighting scenes for all lighting devices connected to the system. The scene controller can send commands to as few as six and as many as 20 scene-capable dimmers per circuit.

“X-10 has been out there for 30 years, and it works well,” McClellan says. “There's a wide variety of products available for X-10. However, the technology is aging. There have been some improvements made, but it just isn't quite up to the professional installation standards it should be.”

Installers and users alike cite interference as the largest drawback of X-10 systems. Carrier frequencies being transmitted through household wiring are subject to attenuation and noise interference, which may cause reliability issues. Filters and repeaters must then be installed in the system to solve these problems.

“Certainly, the drawback with X-10 is the fact that you have to filter stuff and make sure you have clear and strong signals all throughout the house,” says Rick Wlodyga, licensed electrician and owner of Technical Comfort, Laguna Niguel, Calif. “And then there is always the risk that the homeowner would put in a new plasma TV without letting you know, and all of a sudden you've got interference issues. Then your system won't work. So the technologies that are more interference-immune from how people actually use their homes are better.”

X-10 evolution

Addressing the reliability issues of X-10, Irvine, Calif.-based Smartlabs Inc. developed Insteon, a proprietary combination wireless/wired dual-mesh technology. Insteon transmits communication signals over home electrical wiring, as well as through RF transmissions. “It wasn't until Smarthome came up with the ability to increase the signal multiple times within a home that turned it around for me as far as being able to help some people that were having problems [with X-10 systems],” Top Hat Automation's Lee says.

In addition, filtering technology has improved, and equipment to test signals in homes became available. But some customers still weren't satisfied and have turned to Insteon. “X-10 still isn't 100 percent,” Lee says. “I've had clients that just recently had an X-10 system, and I switched more than 120 switches in their house to Insteon. It operates on a higher voltage and a different bandwidth that's not subject to the same noise issues as the X-10.”

Lee says the X-10 operated on a quieter part of the sine wave, so any noise would impair its ability to understand itself. Insteon technology operates on a different part of the sine wave with a boosted signal, so it has proven to be more reliable.

Product lines

One advantage X-10 has over its newer competitor is that its longevity has given manufacturers time to create a full range of complementary products that are already on the market. Items such as wireless remotes, plug-in modules and different fixture modules are compatible and available for installation. These products are desirable to homeowners looking for a full range of options for their systems. “Probably the biggest draw to X-10 is you can immediately offer everybody everything from compatible motion detectors to RF devices,” Wlodyga says. “Most end customers don't really care how it works, just that it works. To me, the full complement of technologies is the main thing.”

Time is not on X-10's side, however. In the next six months, several lines of new products for Insteon-based products are scheduled to be launched. “I think that over the next six months we're going to see quite a few things that will take away that comment I just made about the disadvantage of not having all the proliferation of different devices,” Wlodyga clarifies. “And with Insteon, putting them in is much simpler. Now, programming and making them all talk to each other and doing complex algorithms is more complicated in X-10. Within months, the products that the manufacturer and some of their partners put out will pretty much level that playing field.”

A two-way protocol

Components for the UPB protocol have also begun proliferating the literal and virtual shelves of product distributors. Introduced by Power line Control Systems, Northridge, Calif., in 1999 for commercial applications, UPB has recently become more widely used in residential installations. UPB uses standard power lines to send two-way signals. Its patented communications method is called “Pulse Position Modulation (PPM),” which is based on timed pulses — as strong as 40V — instead of a carrier frequency. Two-way communication allows the system to verify that the commands were successfully received.

“The thing that's innate about UPB that is not in X-10 is this confirmation,” McClellan says. “Let's say an automation controller sends a signal to turn on the front porch light. We know it works because the switch sends back a confirmation. The confirmation goes back to the controller, so the controller knows the signal went out and was received because it gets a confirmation back.”

According to McClellan, this attribute allows the system to be set up more quickly and reduce callbacks. In addition, unlike X-10, there are no repeaters or phase couplers required.

“Clearly, UPB has got some major advantages over X-10 in that it's a lot more bulletproof,” Wlodyga says. “You can throw it in and have less things that will interfere with it. So from that standpoint it's been a plus to install.”

But according to some contractors, UPB is not cost effective. “It's just too expensive for me to put it in most homes,” Lee says. “I'm not badmouthing it, but it's just not something I install.”

For Wlodyga, the risks of all three systems are similar. “You've gotta make sure you've got a strong enough signal,” he says. “The larger the home, the more chances there are for signal degradation. Really, when I'm budgeting a project — whether it's RF or a power-line carrier — as far as my actual timeline budget to make sure the signal gets around, it's about even.”

Despite the problems with each system, home automation — and lighting control in particular — should continue to grow in popularity as more and more homeowners become educated about the benefits and possibilities these systems have to offer. “Most people just don't realize their options,” Lee says. “To be able to walk into a house and hit one button in a 10,000-square-foot house and create a whole mood throughout the house for a party — if people knew they could do that relatively inexpensively, more people would do it.”

Beauty is in the Eye of the Beholder

Aesthetics may be one of the customer's main concerns, but it's second only to the functionality of the system, says Rick Wlodyga, licensed electrician and owner of Technical Comfort, Laguna Niguel, Calif. Customers want to know what the keypad looks like and what sort of functions it will allow. “The kind of rubberized-looking keytops are not all that attractive to customers,” he says. “They'd just as soon have something that doesn't look too different than the rest of their house and doesn't look too strange to visitors.”

For example, one of Wlodyga's clients, who is an interior decorator, didn't want to have the round, rubberized buttons on his keypad because he didn't like the way they absorbed oils and fragrances. The hard plastic keys are most preferred, and older customers often request larger font sizes on the controllers. Even better would be to give the customer a choice in the way the system looks as well as the way it works.