On Feb 26, 4:30*pm, DerbyDad03 wrote:
On Feb 26, 6:45*pm, "
wrote:
On Sun, 26 Feb 2012 14:59:42 -0800 (PST), DerbyDad03
wrote:
On Feb 26, 5:32*pm, "
wrote:
On Sun, 26 Feb 2012 17:27:42 -0500, "Ralph Mowery"
wrote:
"Tony Hwang" wrote in message
...
Hi,
I always have Simpson 260 handy working on problem like this. Fluke is for
some other use.
It might not show up in the circuits in a house, but at work on some of the
480 volt 3 phase circuits I could show some of the same things with a
Simpson 260. *Start with the voltage on the highest scale and don't worry
about the voltage, just pay attention on how far up the meter goes, then
switch to the lower ranges in order. *On many of the 'phantom' voltages, the
pointer on the meter will not move very far up or down.
I have an assortment of Fluke and other meters I can use, but mostly grab
the 260 and the old analog Amprobe for current measurments.
I do not have one to check it out, but I understand that some of the newer
digital test meters have a low input resistance to help eliminate the
'phantom' voltage problem.
Just plug an incandescent light bulb into the circuit.
With a lamp plugged into the same GFCI, and turned on, I get the same
"oddball" readings at the GFCI.
With no load on 2 other circuits that I tested, I get the expected
readings of 0 between ground and neutral, 115V between hot and ground.
Fluke 75 multimeter.
Read my later reply, after you'd posted this information. *Essentially, you do
have an open ground, like the TLT was telling you. *Where it is in the next
question. *Use the TLT on another outlet in this circuit. *Testing both an
outlet before and one after will nail it down pretty well. *If the one after
is fine, then there is a good chance that the fault is within the GFCI itself.
Well, at least we've stopped talking about the meter and/or the
operator, which so many wanted to blame as the cause.
"Testing both an outlet before and one after will nail it down
pretty well."
Can't do that. There is no receptacle before the GFCI and everything
after it is ungrounded. The GFCI was installed so that 3 pronged
receptacles could be installed downstream. Obviously, they'll all read
"open ground".
However, here's the latest:
I opened the junction box just before the GFCI and disconnected the
line in Romex feed, which had a ground wire. I then ran a suicide cord
from a known good receptacle in my shop to the Romex going to the
GFCI. The GFCI now reads correctly when using the tester and there are
no strange readings between the current carriers and ground. Same
meter, same operator. ;-)
I traced the original Romex back to another junction box which houses
a light fixture over the utility tub. That box has 2 other wires
associated with it, one obviously being the feed but the other one
disappears up into a wall. I'll need to open that box to see if
there's a ground in there, otherwise I'll be pulling a new wire from
the panel to the GFCI's junction box.
Too late to play now, SWMBO is cooking and killing that circuit kills
the kitchen lights too.
You're homing in on the solution.
My best guess..... loose connection between panel & GFI box.
btw those three light testers can be fooled by some unusual conditions
here's a link to a website
http://www.thecircuitdetective.com/test.htm
Scroll down about half way & there is a detailed discussion of the 3-
prong plug in tester.
These plug-in testers are handy but not perfect, they can give
misleading results in some situations.
cheers
Bob