Chapter Corner

Protection Without Exception

Posted in: Features, May/June 2018

Since the 1960s, receptacles and circuit breakers with GFCI technology have become standard in homes to protect occupants from electric shock. Required by the NEC for outlets located in certain wet or damp locations, such as near bathroom sinks, kitchen countertops, bathtubs, and showers, GFCI receptacles monitor variations in the electrical current flowing through the line. In instances where a person accidentally becomes part of an electrical circuit, a GFCI receptacle would immediately trip, preventing electrical current from going through a person on its way to ground. It’s a technology that can save lives.
But did you know that GFCI circuit breakers don’t have to adhere to the same safety standards that govern GFCI receptacles? Until only recently, UL safety standards for GFCI circuit breakers included exceptions which
may allow for unprotected power to remain flowing through a circuit breaker that has reached end of life.
GFCI end of life is defined as when a GFCI is incapable of providing ground fault protection and passing its internal test function. UL 943 Self-Test GFCI End of Life standard states that when a self-test GFCI reaches end of life it must either:
  • Deny power with inability to reset;
  • Give a visual or audible indication; or
  • Trip with reset ability, subject to the next test cycle or repeat tripping
When this standard was adopted it assumed that GFCIs, like all consumer products, have a limited life expectancy
and would eventually reach a point where they could no longer provide ground fault protection. As such, UL included a provision for testing and resetting GFCI devices and encouraged users to test their devices monthly. However, even when diligent users did follow through with regular testing, a GFCI device without true power denial features could potentially be reset and continue to provide power without providing ground fault protection. Naturally, the assumption was that if power was available, so was protection. 
A research study based on information collected by members of the American Society of Home Inspectors (ASHI) revealed that an alarming number of GFCI devices in homes throughout the U.S. were not providing ground fault protection when tested. The field study reviewed data from more than 13,000 building inspections and found that, on average, 15 percent of GFCIs were inoperative when tested. In areas of the country that experience a high volume of lightning, such as central Florida and the great plains, there was an even higher
incidence of failure, with as many as 58 percent of GFCIs not working properly.
These findings were the catalyst that helped propel the industry toward the reset/lockout style GFCI devices use
today, along with heightened UL safety standards for end of life. However, while these safety standards were universally applied to all GFCI receptacles, many GFCI circuit breakers on the market today took advantage of exceptions in the standards that could allow them to be reset and continue to provide power without ground fault protection. These exceptions pertain specifically to silicone-controlled rectifiers (SCR) and solenoids - two components common to all tripping mechanisms in both receptacles and circuit breakers with GFCI technology. Failure of either of these components may allow the circuit breaker to remain energized.
So what does this mean to the end user? If a circuit breaker with GFCI technology reaches end of life and is no longer providing ground fault protection as a result of SCR or solenoid failure, it may still be reset and continue to provide unprotected power with no indication required to the end user.
Fortunately, UL has recently updated its standards to close these loopholes for GFCI circuit breakers. However, manufacturers will have more than three years to comply with the new standards, meaning many circuit breakers currently in operation and on the market will be unable to provide complete ground fault protection.
Thankfully, electrical contractors don’t have to wait that long to provide complete protection against ground faults. Leviton, a leading brand of smart, whole-home electrical solutions, recently introduced the first true power-denial circuit breaker on the market, along with its new Leviton Load Center. Leviton’s new GFCI and AFCI/GFCI circuit breakers feature patented reset lockout technology that already meets the revised standard. If one of these breakers experiences an SCR or solenoid failure, it cannot be reset to provide unprotected power like competing circuit breakers, adding an additional level of protection against electric shock.
The Leviton Load Center not only provides an added level of safety but is quicker and easier to install than most other load centers and has an approachable and intuitive design. It features an all plug-on circuit breakers with branch wires terminating at custom lugs in the panel, so all connections are made at the final insertion of the circuit breaker. This makes wiring easier and neater and eliminates the need for pigtails. Industry-first line-side powered LED indicators remain lit even when a breaker is tripped, clearly showing trip condition and type of fault for easier diagnostics.
Since Leviton’s circuit breakers were introduced in early March, UL has updated its safety standards to require that future GFCI circuit breakers provide the same level of uncompromised protection currently offered by Leviton. But for electrical contractors looking for an immediate solution for complete ground fault protection, Leviton’s circuit breakers are years ahead of the curve and the only option available now.
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James Sherman is director of marketing, residential, for Leviton Manufacturing Co., Inc.