On 01 Dec 2004 05:00:06 GMT, (Greg) wrote:

Do not take advice from people who don't have a code book.
You can run a single conductor if it is not subject to damage. Green,
green/yellow or bare.


250.130C) Nongrounding Receptacle Replacement or Branch Circuit Extensions. The
equipment grounding conductor of a grounding-type receptacle or a
branch-circuit extension shall be permitted to be connected to any of the
following:
(1) Any accessible point on the grounding electrode system as described in
250.50
(2) Any accessible point on the grounding electrode conductor
(3) The equipment grounding terminal bar within the enclosure where the
branch circuit for the receptacle or branch circuit originates
(4) For grounded systems, the grounded service conductor within the service
equipment enclosure
(5) For ungrounded systems, the grounding terminal bar within the service
equipment enclosure
FPN:See 406.3(D) for the use of a ground-fault circuit-interrupting type of
receptacle.
Section 250.130(C) applies to both ungrounded and grounded systems. It permits
a nongrounding-type receptacle to be replaced with a grounding-type receptacle
under the following conditions.
(1) The branch circuit does not contain an equipment ground.
(2) An existing branch circuit is being extended for additional receptacle
outlets.
(3) An equipment grounding conductor is connected between the receptacle
grounding terminal and any accessible point on the grounding electrode system.
Because of the requirements of 250.52(A)(1), an interior metal water pipe more
than 5 ft from the point of entrance of the water pipe into the building is no
longer allowed to serve as a connection to the grounding electrode conductor.

This is made clear in the 2002 NEC Handbook, which the above quote
comes from. The NEC codebook does not contain the clarification
interpretation and accompanying illustration making the installation
clearly allowed under NEC 2002. I'll check the NEC 2005 today but
it's probably the same. I love these discussions, I learn something
once in a while.

Dan