Electrical – What options are there to achieve both grounding/ground-fault and arc-fault protection on old 2-wire circuits

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The three receptacle circuits in my house are 2-wire NM, but have 3-prong receptacles. My electrician recommended and installed GFCI breakers to provide "grounding" to these circuits. I now realize that arc-fault protection on these circuits would be a good-idea for safety. The wiring for the branch circuits was not being "modified, replaced, or extended" (NEC 210.12(B)), so I don't think AFCI is technically required by code, but I am surprised the electrician didn't recommend it in addition to GFCI protection.

I can call the electrician to come back and fix, but I'd like to know what my options are in advance. I think the options are:

  1. Replace GFCI breakers with CAFCI breakers and add GFCI receptacles to the first-outlet on each circuit. (Cost: 3x$50 + 3x$20 = $210 plus labor)
  2. Keep GFCI breakers and add AFCI receptacles to the first-outlet on each circuit (allowed by 210.12(B)(2) and 406.4(D)(2)). (Cost: 3x$30 = $90).
  3. Replace GFCI breakers with Dual Function AFCI/GFCI breakers. May not be available for my GE panel. GE makes them, but I don't see them available for purchase anywhere.

Option 2 sounds nice, but I haven't heard of this before and the NEC appears to be ambiguous on this specific situation. AFCISafety.org also appears to be ambiguous:

An AFCI can be used in conjunction with GFCI protection to provide both arcing fault protection as well as 5mA ground fault (people) protection. A common way to provide both types of protection is to use an AFCI circuit breaker and a GFCI receptacle.

Am I missing anything?

Best Answer

First off. The only way to provide proper "grounding", is to install a grounding conductor from the panel to each outlet. Providing AFCI and GFCI protection to the circuits is helpful, but these devices will not provide "grounding".

If you switch from 2-prong receptacles to 3-prong on these circuits, you should not connect anything to the grounding screw of the receptacles. You should also (technically) install labels at each outlet that read "GFCI protection" and "No Equipment Ground". Though, these labels aren't common in residential situations.

  1. Replace GFCI breakers with CAFCI breakers and add GFCI receptacles to the first-outlet on each circuit.

This is probably going to be your best bet. In this scenario, the CAFCI breaker provides protection to the entire circuit. The GFCI protection being at the first outlet, means that while the wiring from the panel to this location is not protected, the rest of the circuit is protected.

  1. Keep GFCI breakers and add AFCI receptacles to the first-outlet on each circuit.

This isn't a terrible option, although the AFCI device will not be protecting the wiring between the panel and the device. Also note that an AFCI device only detects line to ground arcs (parallel arcs), while a CAFCI device detects both line to ground and line to line arcs (parallel and series arcs).

  1. Replace GFCI breakers with Dual Function AFCI/GFCI breakers.

If you could actually find these (and could afford them), this would probably be your best course of action. Unfortunately, these devices probably don't exists (yet) from most manufacturers.

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