Arc-D-Tect™ Arc-Fault Circuit Interrupters Can Help You Meet the NEC®
Comply with the NEC and CEC Arc-Fault Circuit Interrupter Requirement in Commercial Dwelling Units
Square D brand AFCIs can be easily distinguished by their
white TEST buttons. |
Supporting the electrical industry’s commitment to electrical safety
The NEC has required that all branch circuits supplying outlets in dwelling unit bedrooms be protected by a combination AFCI since January 1, 2008.
Dwelling units are defined in Article 100 of the NEC as “One or more rooms for the use of one or more persons as a housekeeping unit with space for eating, living, and sleeping, and permanent provisions for cooking and sanitation.” This may include dormitories, extended-stay hotels, or other living units where the occupancy meets the NEC definition of a dwelling unit.
The combination AFCI circuit breaker provides arc fault protection for the branch circuit, as well as protection for cord sets and power-supply cords. When an arcing event is detected, the AFCI analyzes the event and the circuit breaker opens when it determines a hazardous condition exists.
The diagrams below illustrate the differences between parallel and series arc faults, both of which would be detected by a combination AFCI device.
Series Arc Fault |
Parallel Arc Fault |
With the enhanced protection of a combination AFCI, arcs are detected at levels down to 5 A, including series arcs, parallel arcs, and 50 mA linetoground arcs. Because series arcs are often associated with damaged devices or cord sets, the enhanced protection that a combination AFCI provides in this area is significant.
Schneider Electric’s commitment to electrical safety continues with the combination AFCI
Schneider Electric, through its Square D® brand of circuit breakers, has released the world’s first commercially available combination arc-fault circuit breaker in January 1, 2008.
The combination AFCI “combines” the protection of the branch/feeder AFCI and the outlet circuit AFCI to provide the most comprehensive arc fault protection. The UL Standard 1699, Arc-Fault Interrupters describes the types of AFCIs as follows:
Branch/Feeder AFCI: A device intended to be installed at the origin of a branch circuit or feeder, such as at a panelboard. It is intended to provide protection of the branch circuit wiring or feeder wiring (or both) against unwanted effects of arcing. This device also provides limited protection to branch circuit extension wiring. It may be a circuit-breaker type device or a device in its own enclosure mounted at or near a panelboard.
Outlet Circuit AFCI: A device intended to be installed at a branch circuit outlet, such as at an outlet box. It is intended to provide protection of cord sets and power-supply cords connected to it (when provided with receptacle outlets) against the unwanted effects of arcing. This device may provide feed-through protection of the cord sets and power-supply cords connected to downstream receptacles.
Combination AFCI: An AFCI that complies with the requirements for both branch/feeder and outlet circuit AFCIs. It is intended to protect downstream branch circuit wiring and cord sets, and power supply cords.
| Arc Condition | Branch/Feeder | Outlet Circuit | Combination |
|---|---|---|---|
| Line-to-neutral | Yes | Yes | Yes |
| Line-to-ground | Yes | Yes | Yes |
| Series arcing | No | Yes | Yes |
| Protection of entire branch circuit | Yes | No | Yes* |
When Should You Install Arc-Fault Circuit Interrupters?
Consider adding AFCI protection for both new and existing dwelling units. Older structures with ordinary circuit breakers can benefit from the added protection against the arcing faults that can occur in aging wiring systems.
The wiring of a combination AFCI circuit breaker is identical to that used for a standard branch/feeder AFCI or GFCI circuit breaker. Be sure to have a qualified electrician install AFCIs.
Dual Function Circuit Breaker: A Dual Function Circuit Breaker is a combination of Arc Fault and Ground Fault Protection in one circuit breaker. Dual Function Circuit Breakers protect the entire circuit on which they are installed. For more information on Square D Advanced Function Circuit Breakers please review RP19520116.
Contact your local Schneider Electric sales representative for more information about this circuit protection product.