FlatWire is a division of Southwire Company (Carrollton, Ga.), North America's biggest manufacturer of electrical wire and cable. Its eponymous product is a flat copper wire that can be glued to walls and ceilings, then made nearly invisible with a simple coat of spackle and paint.

The wiring—composed of thin strips of copper encapsulated in transparent insulators—was recently written into the National Electric Code (NEC), thereby making it eligible for widespread adoption. FlatWire had earlier met NEC specs for low-voltage signal wiring, but the new listing, under article 382, claims FlatWire is also safe for carrying 110-volt line current. (NEC article 382 classifies FlatWire as "concealable nonmetallic extensions"; in this context, the product is nonmetallic in that it does not require a metal conduit.)

FlatWire is also undergoing the voluntary listing process with Underwriters Laboratories. That process is expected to be completed by the end of 2008.

Robb Sexton, president of FlatWire Technologies, claimed the product is the "safest wiring ever created," adding that the "trick was to make a flat wire that is essentially invisible on a wall's surface, but safe to carry 110 volts at 15 amps."

Sexton invented FlatWire after founding DeCorp Americas Inc., which was acquired by Southwire in 2005. Since then he has dedicated his time to perfecting different form factors of FlatWire for all types of signals. Today, in addition to the new power-cable replacement product, there are FlatWire versions for replacing Ethernet RJ-45, coaxial cable, three-conductor (RGB) component-video cable, S-video cable, stereo audio cable and speaker wire.

"Power-cable replacement was our biggest challenge; we've been through three iterations to get it right," said Sexton. "What we had to do was invent a whole new design. It's still like one wide copper strip, as are our other models, but actually it is a stack of five conductive layers."

The two outside layers are grounded, and the next two layers are neutral, leaving the "hot" conductor encapsulated in the middle.

"The risk of shock or fire has been completely neutralized, because if this wire is ever penetrated, you always hit ground first and neutral second. By the time you hit the hot layer, you have created a short, which trips the circuit breaker every time," said Sexton.

FlatWire electrical engineers also create active electronics that monitor for ground faults, mitigate arcs and act as a secondary overcurrent device. The intelligent device constantly monitors 110-V FlatWire installations to detect faults that could causes shocks or fires.

"We've made it into a very sophisticated intelligent device; it's chock full of goodness from an EE's viewpoint," said Sexton. "It's microprocessor-controlled, with on-board memory and many active and passive components, and is smart enough to know when you plug it into an outlet that is wired wrong."

The active safety device, which looks like a stylized wall wart, opens its own circuit breaker if any fault is detected.

For the future, FlatWire is working on variable length High Definition Multimedia Interface cabling that it hopes to have into production later this year. Its HDMI cable, like its other offerings, will be fashioned so that installers can cut it to size, glue it to walls, attach solder-free connectors with standard pinouts to each end, and then conceal the cable with a coat of spackle and paint.

FlatWire applications under development include industrial deployments that replace wiring harnesses inside equipment boxes, instead using the inside walls of enclosures as wiring planes, and automotive versions that use the flat panels beneath a car's carpet as a wiring plane to replace bulky wire harnesses.