Replacing 2-prong outlets with GFCI outlets

[Kenton H. Shepard, CMI]

I know this has been discussed many times but I can't get the search engine to work for me...
Can anyone give me a link to a good massage board discussion on replacing 2-prong outlets with GFCI outlets?

Thanks,

Kent

[Michael Larson]

Try this.

[whandley]

Try this one...

http://www.cpsc.gov/CPSCPUB/PUBS/524.html

[Michael Larson]

Here is a recent thread on the issue.

http://www.nachi.org/forum/f19/need-help-new-service-old-wiring-5111/index2.html

[Kenton H. Shepard, CMI]

I'm hoping to find a discussion on how well it actually works, since there's no grounding conductor and the GFCI is often only grounded (if at all) to the ungrounded box in which it's mounted.

Also, in this situation, does the upstream GFCI protect outlets downstream if the downstream outlets have been changed out to 3-prong and grounded to their (ungrounded) boxes?

[Bruce A. King]

If wired correctly no ground is needed, the GFCI circuitry only compares the hot and neutral current and trips when necessary. The lost current is assumed to travel to ground through a person but it can travel via wet extension cords or chaffed wires too.

There was some discussion before on here about a new type of GFCI that will require a ground connection to operate.

A connection to a metal box often is not a proper ground when the panel only has 2 wire cables and no metal conduit present.

[Paul W. Abernathy]

http://www.nachi.org/forum/f19/2-prong-outlets-narrative-examples-5562/

[David P. Valley]

Attachment 4278
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