Installed two Leviton GFCIs yesterday, each one for that outlet only, not
protecting anything else downstream. One works just fine. The other one
doesn't: it resets OK and powers up, plug-in circuit tester shows it's wired
correctly, test button _on_the_plug-in_tester_ trips the GFCI, it resets OK,
but the test button on the GFCI itself does *not* trip it. Cycled through this
repeatedly, with no change in behavior.

Took the misbehaving one back to the retailer and exchanged it. Installed the
replacement: identical behavior.

Swapped it with the other GFCI to see if the problem would follow the unit,
or stay with the box. *Both* units work properly.

Speculations as to what's going on? I'm at a complete loss to explain this.

--
Regards,
Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt.
And who wants to leave buttprints in the sands of time?

(Doug Miller) wrote:
Installed two Leviton GFCIs yesterday, each one for that outlet only, not
protecting anything else downstream. One works just fine. The other one
doesn't: it resets OK and powers up, plug-in circuit tester shows it's wired
correctly, test button _on_the_plug-in_tester_ trips the GFCI, it resets OK,
but the test button on the GFCI itself does *not* trip it. Cycled through this
repeatedly, with no change in behavior.

Took the misbehaving one back to the retailer and exchanged it. Installed the
replacement: identical behavior.

Swapped it with the other GFCI to see if the problem would follow the unit,
or stay with the box. *Both* units work properly.

Speculations as to what's going on? I'm at a complete loss to explain this.

Intermittent ground in the flaky outlet box? Offhand, you'd think that since
a ground isn't necessary for GFCI operation, you wouldn't need one for testing,
but I'm at a loss (at least until the caffeine kicks in) how one could test GFCI
operation without a ground to fault to...

On Wed, 13 Apr 2005 14:04:39 GMT, (Doug Miller)
wrote:

Installed two Leviton GFCIs yesterday, each one for that outlet only, not
protecting anything else downstream. One works just fine. The other one
doesn't: it resets OK and powers up, plug-in circuit tester shows it's wired
correctly, test button _on_the_plug-in_tester_ trips the GFCI, it resets OK,
but the test button on the GFCI itself does *not* trip it. Cycled through this
repeatedly, with no change in behavior.

Took the misbehaving one back to the retailer and exchanged it. Installed the
replacement: identical behavior.

Swapped it with the other GFCI to see if the problem would follow the unit,
or stay with the box. *Both* units work properly.

Speculations as to what's going on? I'm at a complete loss to explain this.

Tolerances.

In article , wrote:

Intermittent ground in the flaky outlet box? Offhand, you'd think that since
a ground isn't necessary for GFCI operation, you wouldn't need one for testing,
but I'm at a loss (at least until the caffeine kicks in) how one could test
GFCI operation without a ground to fault to...

While that might explain the test button on the GFCI not working, how about
the test button on my plug-in tester? That tripped the GFCI _every_time_.

--
Regards,
Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt.
And who wants to leave buttprints in the sands of time?

(Doug Miller) wrote:
In article , wrote:

Intermittent ground in the flaky outlet box? Offhand, you'd think that since
a ground isn't necessary for GFCI operation, you wouldn't need one for testing,
but I'm at a loss (at least until the caffeine kicks in) how one could test
GFCI operation without a ground to fault to...

While that might explain the test button on the GFCI not working, how about
the test button on my plug-in tester? That tripped the GFCI _every_time_.

Gah. OK, how 'bout there's already some ground leakage from the neutral to
ground (capacitive coupling or something), the "test" button on the GFCI is set
to fault the hot to ground, and the "test" load is close enough to the hairy
edge that it can't quite swing the differential current back over the "trip"
level. The tester, OTOH, uses a larger load, so it swings it all the way over
to the trip level. Now, how the heck a neutral (even a floating one) could leak
enough current to ground for that to happen is left as an exercise for the
student (meaning, I can't really think of a way).

OK, so I'm blowing a smoke cloud that can be seen for miles. Damned if I can
come up with a reasonable explanation, either...

According to Andy Hill :
(Doug Miller) wrote:
In article , wrote:

Intermittent ground in the flaky outlet box? Offhand, you'd think that since
a ground isn't necessary for GFCI operation, you wouldn't need one for testing,
but I'm at a loss (at least until the caffeine kicks in) how one could test
GFCI operation without a ground to fault to...

While that might explain the test button on the GFCI not working, how about
the test button on my plug-in tester? That tripped the GFCI _every_time_.

Gah. OK, how 'bout there's already some ground leakage from the neutral to
ground (capacitive coupling or something), the "test" button on the GFCI is set
to fault the hot to ground, and the "test" load is close enough to the hairy
edge that it can't quite swing the differential current back over the "trip"
level. The tester, OTOH, uses a larger load, so it swings it all the way over
to the trip level. Now, how the heck a neutral (even a floating one) could leak
enough current to ground for that to happen is left as an exercise for the
student (meaning, I can't really think of a way).

A GFCI's test button is designed to trip the GFCI even without a ground. It does
this by shorting one of the output leads through a resistor to an input lead, or
something like that (so the output leads are imbalanced).

A GFCI tester cannot do that (because it doesn't have access to the "input leads"),
so it simply runs some current from the hot wire to the ground (and hence it
needs a ground to operate properly).

It seems to me that if the circuit has an open neutral, the GFCI test button
wouldn't trip it, but the standalone tester _would_ trip it.

OK, so I'm blowing a smoke cloud that can be seen for miles. Damned if I can
come up with a reasonable explanation, either...


--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.

"Doug Miller" wrote in message
...
Installed two Leviton GFCIs yesterday, each one for that outlet
only, not
protecting anything else downstream. One works just fine. The other
one
doesn't: it resets OK and powers up, plug-in circuit tester shows
it's wired
correctly, test button _on_the_plug-in_tester_ trips the GFCI, it
resets OK,
but the test button on the GFCI itself does *not* trip it. Cycled
through this
repeatedly, with no change in behavior.

Took the misbehaving one back to the retailer and exchanged it.
Installed the
replacement: identical behavior.

Swapped it with the other GFCI to see if the problem would follow
the unit,
or stay with the box. *Both* units work properly.

Speculations as to what's going on? I'm at a complete loss to
explain this.


Doug,

I've found that some of these require a lot of pressure with the
thumbnail to
trip.

Ed

Doug Miller wrote:
Installed two Leviton GFCIs yesterday, each one for that outlet only, not
protecting anything else downstream. One works just fine. The other one
doesn't: it resets OK and powers up, plug-in circuit tester shows it's wired
correctly, test button _on_the_plug-in_tester_ trips the GFCI, it resets OK,
but the test button on the GFCI itself does *not* trip it. Cycled through this
repeatedly, with no change in behavior.

Took the misbehaving one back to the retailer and exchanged it. Installed the
replacement: identical behavior.

Swapped it with the other GFCI to see if the problem would follow the unit,
or stay with the box. *Both* units work properly.

Speculations as to what's going on? I'm at a complete loss to explain this.

--
Regards,
Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt.
And who wants to leave buttprints in the sands of time?

Doug
To undestand why the two test produced different results you need to
understand how each test load is applied. The plug in tester shunts the
test current to the equipment grounding conductor of the circuit. The
built in test button shunts the test current from the ungrounded
current carrying conductor (the Hot) on load side of the monitoring coil
to the grounded current carrying conductor (the neutral) on the line
side of the monitoring coil. What you had was a high resistance neutral
connection on the line side of the GFCI that would not carry enough of
the test current to trip the GFCI. Since the plug in tester was
shunting the test current to the EGC it had a solid path for the test
current. The internal tester was trying to use the neutral and was not
getting a low impedance path back to the power source. Something you
did in changing out the units has restored the neutral path and now it
is of low enough impedance to trip the GFCI. The bad news is that may
well be temporary. You may have an intermittent bad termination or
splice in the neutral. An Ideal Suretest or a manually applied dummy
load with a good meter can test my theory.
--
Tom Horne

installation manual on one I just got says to plug in a lamp when testing.
It wasn't clear if this was just so you know it worked or because it needs a
load to function correctly. Does it work any differently when you have
something plugged in and turned on.


"Doug Miller" wrote in message
...
Installed two Leviton GFCIs yesterday, each one for that outlet only, not
protecting anything else downstream. One works just fine. The other one
doesn't: it resets OK and powers up, plug-in circuit tester shows it's
wired
correctly, test button _on_the_plug-in_tester_ trips the GFCI, it resets
OK,
but the test button on the GFCI itself does *not* trip it. Cycled through
this
repeatedly, with no change in behavior.

Took the misbehaving one back to the retailer and exchanged it. Installed
the
replacement: identical behavior.

Swapped it with the other GFCI to see if the problem would follow the
unit,
or stay with the box. *Both* units work properly.

Speculations as to what's going on? I'm at a complete loss to explain
this.

--
Regards,
Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt.
And who wants to leave buttprints in the sands of time?

In article , (Chris Lewis) wrote:

It seems to me that if the circuit has an open neutral, the GFCI test button
wouldn't trip it, but the standalone tester _would_ trip it.

But the plug-in tester showed everything correct, and 120V appliances plugged
into the GFCI recep operate normally. This would eliminate an open neutral.

--
Regards,
Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt.
And who wants to leave buttprints in the sands of time?

In article , "Jag Man" wrote:

I've found that some of these require a lot of pressure with the
thumbnail to
trip.

Yep, I know. I set the end of a screwdriver on it, and leaned into it pretty
heavy, after three tries with the thumbnail failed. Still no trip.

--
Regards,
Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt.
And who wants to leave buttprints in the sands of time?

In article et, "AutoTracer" wrote:
installation manual on one I just got says to plug in a lamp when testing.
It wasn't clear if this was just so you know it worked or because it needs a
load to function correctly. Does it work any differently when you have
something plugged in and turned on.

Made no difference.

--
Regards,
Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt.
And who wants to leave buttprints in the sands of time?

According to Doug Miller :
In article , (Chris Lewis) wrote:

It seems to me that if the circuit has an open neutral, the GFCI test button
wouldn't trip it, but the standalone tester _would_ trip it.

But the plug-in tester showed everything correct, and 120V appliances plugged
into the GFCI recep operate normally. This would eliminate an open neutral.

If the plug-in tester showed that the hot, neutral and ground were on the
right prongs, it can trip the GFCI, and two prong devices act normally,
then I'm totally stumped.

Oh, waitasec, are you sure you got the load and line wires the right way
around? I think you said it was the dead-end of the circuit - no feedthru,
you're _sure_ the power feed is on the "line" side?
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.

In article , (Chris Lewis) wrote:
According to Doug Miller :
In article ,
(Chris Lewis) wrote:

It seems to me that if the circuit has an open neutral, the GFCI test button
wouldn't trip it, but the standalone tester _would_ trip it.

But the plug-in tester showed everything correct, and 120V appliances plugged
into the GFCI recep operate normally. This would eliminate an open neutral.

If the plug-in tester showed that the hot, neutral and ground were on the
right prongs, it can trip the GFCI, and two prong devices act normally,

Yes, yes, and yes.

then I'm totally stumped.

Me too.

Oh, waitasec, are you sure you got the load and line wires the right way
around? I think you said it was the dead-end of the circuit - no feedthru,
you're _sure_ the power feed is on the "line" side?

Absolutely certain. The unit ships from the factory with yellow tape over the
load terminals, and I did not remove the tape. I also verified that the
terminals that I connected the wires to were labelled "LINE".

--
Regards,
Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt.
And who wants to leave buttprints in the sands of time?

According to Doug Miller :
In article , (Chris Lewis) wrote:
According to Doug Miller :
If the plug-in tester showed that the hot, neutral and ground were on the
right prongs, it can trip the GFCI, and two prong devices act normally,

Yes, yes, and yes.

then I'm totally stumped.

Me too.

Assuming other stuff from this thread (you've swapped GFCI's, and the problem
"stays" with _this_ receptacle box, so the GFCI is known good), clutching at
straws time:

- as per someone else's posting, an intermittent neutral

- something to do with physical stress on the box (and clamp) - are
there any other wires/wirenuts in the box? Are all the connections
recently done/solid? Try moving the connections around. Try pushing
the outlet test button with/without the tester plugged in. "Lean on"
the outlet around while pushing the test button. etc.

[You're checking for loose connections that make/break depending
on being pushed a bit.]

- evil gremlins violating the laws of physics

- Double check that the neutral and hot are the right way around
--
Chris Lewis, Una confibula non set est
It's not just anyone who gets a Starship Cruiser class named after them.

In article , (Chris Lewis) wrote:
According to Doug Miller :
In article ,
(Chris Lewis) wrote:
According to Doug Miller :
If the plug-in tester showed that the hot, neutral and ground were on the
right prongs, it can trip the GFCI, and two prong devices act normally,

Yes, yes, and yes.

then I'm totally stumped.

Me too.

Assuming other stuff from this thread (you've swapped GFCI's, and the problem
"stays" with _this_ receptacle box, so the GFCI is known good), clutching at
straws time:

Not quite... I returned the (apparently defective) GFCI to the retailer and
exchanged it for a new unit - same problem. Swapped it with another,
identical, GFCI already installed and working elsewhere in the house, and both
of them now work normally.

- as per someone else's posting, an intermittent neutral

If that were the case, though, I would have expected to see the lights on the
tester at least flicker. Nada. On steady the whole time.

- something to do with physical stress on the box (and clamp) - are
there any other wires/wirenuts in the box? Are all the connections
recently done/solid? Try moving the connections around. Try pushing
the outlet test button with/without the tester plugged in. "Lean on"
the outlet around while pushing the test button. etc.

No other wires in the box, just the one cable. No wirenuts at all. No
connections to move around. Pressed the outlet test button with, and without,
the tester plugged in - no change. Leaned on it, too - no change.

[You're checking for loose connections that make/break depending
on being pushed a bit.]

Yep. Tried that. No effect.

- evil gremlins violating the laws of physics

Don't know how to test for that. :-)

- Double check that the neutral and hot are the right way around

Tester shows the receptacle is wired correctly - and the tester *does* light
up in the pattern indicating hot-neutral reverse on outlets that were known to
be reversed. (A previous homeowner wasn't quite as careful as he should've
been with some of his projects.)

--
Regards,
Doug Miller (alphageek at milmac dot com)

Nobody ever left footprints in the sands of time by sitting on his butt.
And who wants to leave buttprints in the sands of time?