ARCFAULT BREAKERS

AFCI or Arc Fault Circuit Interrupter is a relatively new edition to residential panels. An arc fault breaker differs from a GFCI outlet or a standard circuit breaker in that it detects slow electrical leaks. A slow leak typically occurs when wiring is compromised but not completely shorted. An example would be if you drove a screw into the wall to hang a painting and inadvertently hit an electrical wire within the wall. Only a full arc (spark, or energy surge), if you hit the hot and the neutral or ground would be detected by a standard circuit breaker. This puncture however, can create enough heat to ignite any nearby combustable material. 

An arc fault breaker will be able to detect much smaller arcs and line leaks. In essence, the detection is accomplished by the use of advanced electronic technology to monitor the circuit for the presence of "normal" and "dangerous" arcing conditions.

 

AFCIs have proven so effective at preventing electrical fires that the National Electrical Code (NEC) requires AFCIs to be installed in almost every room in newly built houses.