Here’s some information that will help answer the question asked of me last night while returning to my hotel in Albany, NY. I attended the local NACHI meeting and Joe Baranowski gave me a lift. This is for you Joe and anyone else who may have had the same question.
Question: Why can a GFCI receptacle be used in old two wire ungrounded circuits?
Replacement of receptacles shall comply with 406.3(D)(1), (D)(2), and (D)(3) as applicable.
**(1) Grounding-Type Receptacles
**Where a grounding means exists in the receptacle enclosure or a grounding conductor is installed in accordance with 250.130©, grounding-type receptacles shall be used and shall be connected to the grounding conductor in accordance with 406.3© or 250.130©.
**(2) Ground-Fault Circuit Interrupters
**Ground-fault circuit-interrupter protected receptacles
shall be provided where replacements are made at receptacle outlets that are required to be so protected elsewhere in this Code.
**(3) Non–grounding-Type Receptacles
**Where grounding means does not exist in the receptacle enclosure, the installation shall comply with (D)(3)(a), (D)(3)(b), or (D)(3)©.
(a) A non–grounding-type receptacle(s) shall be permitted to be replaced with another
(b) A non–grounding-type receptacle(s) shall be permitted to be replaced with a ground-fault circuit interrupter-type of receptacle(s). These receptacles shall be marked ``No
Equipment Ground.’’ An equipment grounding conductor shall not be connected from the
ground-fault circuit-interrupter-type receptacle to any outlet supplied from the
ground-fault circuit-interrupter receptacle.
© A non–grounding-type receptacle(s) shall be permitted to be replaced with a
grounding-type receptacle(s) where supplied through a ground-fault circuit interrupter.
Grounding-type receptacles supplied through the ground-fault circuit interrupter shall be
GFCI Protected'' andNo Equipment Ground.’’ An equipment grounding
conductor shall not be connected between the grounding-type receptacles.
*(http://www.codecheck.com/gfci_principal.htm) am working on a short video clip and will try to make it available here if we can upload audio files or mpg files. If you are attending the convention I will have a table set up showing videos and items related to residential electrical inspections and existing installations and safety. I have images of the entire discussion available if anyone wants them.
I have a full schedule with the classes offered and will attend them so that I can learn more about the HI industry.
I will teach what I know if you will teach me what you know about the other areas beyond my expertise. I will be available anytime if you by me a beer!