3

Is there any reason to use an AFCI receptacle rather than replacing the breaker with an AFCI type? It seems that providing protection on the whole circuit makes much more sense than to just one receptacle. Are there areas where AFCI protected circuits are not allowed?

1

AFCI breakers generally have ground fault protection also, whereas I do not believe AFCI receptacles do. This is sometimes a problem on houses with "shared neutral" circuits (sometimes called Edison Circuits) as the ground fault protection logic will trip the breaker upon application of a load.

There are (or have been, not sure bout 2014 NEC) restrictions on the use of AFCI receptacles: you are/were not allowed to use them unless metal clad conduit was used to protect wiring from the breaker panel to the first receptacle on the circuit (the first receptacle is where you install the AFCI, it protects all downstream receptacles on the circuit).

Please consult a licensed electrician as they should be familiar with local code requirements.

  • 3
    If you have a multi-wire branch circuit (shared "neutral"), you'd have to use a double pole AFCI breaker and it should not trip unless there is a ground- or arc-fault. – Tester101 Jul 26 '14 at 21:59
  • 1
    Most AFCI breakers do not have the same level of protection as GFCI breakers ("In the United States, the GFCI is triggered at 4-6 mA of current-imbalance. The trip-limit for AFCI devices is a current-imbalance of 30-50 mA." Ref1 Ref2 Ref3) – littleturtle Jan 25 '15 at 17:17
  • 1
    Yes, 2014 NEC has those restrictions (metal conduit or encased in concrete). Note that the restrictions are only for new circuits; the NEC allows arc-fault protection with a AFCI outlet on the first receptacle for extensions, replacements, or modifications to existing branch circuits (NEC 2014 210.12(B)). – littleturtle Jan 25 '15 at 17:22
1

Since one main purpose of AFCI circuits is to detect arc faults in the in wall wiring (such as from hammering a nail into the wiring) as well as devices plugged into the wiring, the placement at the breaker is crucial. An AFCI receptacle would not detect an up-stream arc fault. Metal clad conduit protects the wiring from being penetrated by nails and such, which is why NEC has required wiring (as noted in the answer above) be put into metal conduit if you are using an AFCI receptacle .

  • 1
    If you are using an afci breaker you still need a afci receptacle at the home run box if you use a cafci breaker it is enough by itself. – user24125 Aug 26 '14 at 2:25
  • @ user24125, WHAT???? – Speedy Petey Aug 26 '14 at 3:38
  • 1
    The NEC requires combination arc fault protection on most dwelling circuits it will accept a regular arc fault breaker or a few other types that it indicates along with a arc fault receptacle to fulfill the requirement for COMBINATION arc fault protection. – user24125 Aug 26 '14 at 14:17

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.