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DerbyDad03 DerbyDad03 is offline
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Default Adding a 2-wire receptacle with 12/2 wire

On Mar 19, 3:15*pm, (Chris Lewis) wrote:
According to Phisherman :

On Tue, 18 Mar 2008 21:46:13 -0400, "BETA-33"
wrote:
Is that correct, or am I supposed to attach the bare ground wire to each
metal receptacle box even though I don't know if either box is grounded?

If your 2-wire electrical outlet is allowable, then just fold back the
unused ground wire. *Do not install a 3-hole outlet if it is not
properly grounded. *However since this is a safety issue, it would be
a very good investment and wise to upgrade all 2-wire outlets to
grounded outlets.


Code says that if you install a 3-hole outlet, it MUST either be
properly grounded OR, have a GFCI upstream of it (and have a "protected by
GFCI" sticker applied to the new outlet).

_If_ you're relying on GFCI instead of true grounding for a new 3 hole
outlet, its box and receptacle grounding terminal MUST NOT be interconnected
to any other ungrounded outlets, including the GFCI. *So, if you use three
wire to connect from an ungrounded GFCI to an ungrounded 3 hole outlet,
the ground wire should (as Phisherman says) not be connected.

The reason for this being that if you have a series of outlets with
ground interconnect, but no true ground, a hot-ground fault in any device
on any outlet, makes all the other 3-wire devices on all of the outlets
live. *Which could even include plumbing segments (sinks, taps etc),
appliance enclosures etc. *At least with a GFCI, it should trip and
prevent you getting electrocuted. *Without a GFCI or if it fails ... ouch.
--
Chris Lewis,

Age and Treachery will Triumph over Youth and Skill
It's not just anyone who gets a Starship Cruiser class named after them.


Code says that if you install a 3-hole outlet, it MUST either be
properly grounded OR, have a GFCI upstream of it

But doesn't code also say that the GFCI protection option is only
available for existing receptacles? I've found conflicting info on the
web, but most of the info I've found say the old circuits are
grandfathered, but anything new (like the OP's) situation is not
allowed to be simply protected by a GFCI and must be properly
grounded.

Do you know the definitive answer?