TechRay
Member
- Location
- Livingston, Montana
Giving it a go as my first post on Mike's Forum. Occasionally, a customer comes to us with a home inspection that points out non-grounded branch circuits, ie; old clothe 2 conductor romex and/or knob & tube. Short of a complete home rewire, our solution in most cases has been to replace the service, feeder and load center, then refeed all existing non-grounded 120vac branch circuits with Combination Arc Fault/Ground Fault circuit breakers. We then replace all existing receptacles with 3 wire grounded TR devices, labeling each per 406.4 (D) (2) (c).
Recently, we were asked to address electrical issues related to a multi tenant house fire. Structure was a large home at one time, now converted to a nine bedroom rental with common baths and kitchens. Fire was contained to approx. 12' section of wall and roughly 20% of the attic, now exposed non-grounded wiring. The inspector recently conducted a walk through during the course of these repairs and determined that if any 120vac receptacles were replaced, we would be required to either refeed with a new grounded branch circuit, or install a grounding conductor to each receptacle. he quoted Section 607.1.3 of the 2012 International Existing Building Code as his reference. It does state that "a grounding-type receptacle outlet shall be permitted to be grounded to any accessible point on the grounding electrode system," but does not say you can't install grounded type receptacles on non-grounded branch circuits. It references 406.4(D) of NFPA 70 2011 edition for "options" when existing receptacles cannot be replaced with like receptacles. i pointed this out to the inspector and read to him 406.4 (D) (2) (c) of NFPA 2014 edition to which he stated that the IEBC was the overall authority and supersedes guidance from NFPA 70. My questions are;
1) Can someone confirm to me that the use of Combination ARC Fault-Ground Fault circuit breakers on 120vac non-grounded branch circuits allows you to replace non-grounded with grounded type receptacles?
2) Although I believe that the IEBC doesn't even state that you can't use this wiring method, does it have authority over NFPA 70?
3) I've read that Arc Fault circuit breakers react on a line-to-neutral fault. When feeding a non-grounded branch circuit, does the lack of a grounding conductor diminish the operation of the AFCI in any way?
4) Inspector commented on how he can't use his circuit tester to trip a GFI on the above noted installation. I acknowledged that without a ground path to trigger a ground fault test, it wouldn't work, but mentioned that this didn't matter since the test can be done at the breaker "test" button to insure proper function. Can anyone confirm this for me?
I'm posting not just to get clarity on this project, but all future projects regarding these type of residential wiring systems. We want to do it right! Thank you all for input.
Recently, we were asked to address electrical issues related to a multi tenant house fire. Structure was a large home at one time, now converted to a nine bedroom rental with common baths and kitchens. Fire was contained to approx. 12' section of wall and roughly 20% of the attic, now exposed non-grounded wiring. The inspector recently conducted a walk through during the course of these repairs and determined that if any 120vac receptacles were replaced, we would be required to either refeed with a new grounded branch circuit, or install a grounding conductor to each receptacle. he quoted Section 607.1.3 of the 2012 International Existing Building Code as his reference. It does state that "a grounding-type receptacle outlet shall be permitted to be grounded to any accessible point on the grounding electrode system," but does not say you can't install grounded type receptacles on non-grounded branch circuits. It references 406.4(D) of NFPA 70 2011 edition for "options" when existing receptacles cannot be replaced with like receptacles. i pointed this out to the inspector and read to him 406.4 (D) (2) (c) of NFPA 2014 edition to which he stated that the IEBC was the overall authority and supersedes guidance from NFPA 70. My questions are;
1) Can someone confirm to me that the use of Combination ARC Fault-Ground Fault circuit breakers on 120vac non-grounded branch circuits allows you to replace non-grounded with grounded type receptacles?
2) Although I believe that the IEBC doesn't even state that you can't use this wiring method, does it have authority over NFPA 70?
3) I've read that Arc Fault circuit breakers react on a line-to-neutral fault. When feeding a non-grounded branch circuit, does the lack of a grounding conductor diminish the operation of the AFCI in any way?
4) Inspector commented on how he can't use his circuit tester to trip a GFI on the above noted installation. I acknowledged that without a ground path to trigger a ground fault test, it wouldn't work, but mentioned that this didn't matter since the test can be done at the breaker "test" button to insure proper function. Can anyone confirm this for me?
I'm posting not just to get clarity on this project, but all future projects regarding these type of residential wiring systems. We want to do it right! Thank you all for input.