aemeijers wrote:
Jonathan Sachs wrote:
On Tue, 28 Apr 2009 02:45:29 GMT, aemeijers wrote:

Peek in the boxes with a flashlight. If the place was built mid-1960s
or later, odds are there will be a ground wire rolled up under the
romex clamps.

The house was built in 1960. I'm hoping the boxes are grounded, but if
they are not, I'd like to have a Plan B.

And you did plug one of those quick-testers into the grounded outlets
to make sure they really were grounded, right?

I haven't done that yet because I don't own the house yet, but the
home inspector did it, and he reported that several three-hole outlets
in the original living space are _not_ grounded.

The common 3 light testers will reliably show there is a problem (but
could give the wrong problem). If the tester indicates there is a good
ground there probably is, but not necessarily.

If a "grounded" outlet is not grounded it can be replaced by a 2 prong
non-grounding outlet. Most equipment these days does not have a ground pin.

A couple of people suggested going down from the attic. I haven't
examined the attic yet (see above), but I've done that before, and I
can testify that several things can make it impossible, or nearly so:
an outside wall under the eaves; any outside wall that has been
insulated; any wall with bracing. I'm hoping there's a better way.

At least one other post suggested using a GFCI outlet. It is NEC
compliant and gives you a grounded type outlet. But no ground, which may
or may not be a problem. The outlet should be labeled with a "No
equipment ground" label that comes with the outlet. If the circuit
continues past the GFCI outlet, the circuit can be connected to the load
terminals of the GFCI, and outlets downstream will be protected. Outlets
downstream of GFCI protection can be grounding type but must be labeled
"No equipment ground" and "GFCI protected". The ground contacts of these
outlets should not be interconnected by ground wires that are not
actually grounded.

I'm no code expert, but I recall from previous grounded-outlet threads
on here that some folks said running a ground wire via a different route
than the feed wire, was not code-compliant.

Generally all wires have to run together but there is an exception for
an ungrounded outlet - the ground wire can be run by itself. The added
ground wire can go to anywhere on the "grounding electrode system". That
includes the source panel ground bar, the heavy wires connecting to the
grounding electrodes (often the easiest) or the first 5 feet of water
pipe inside the building.

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bud--