I just replaced a regular outlet by a GFCI outlet. A GB outlet tester
with GFCI tester shows that there is no ground (just the same as before
I changed the outlet -- I'll try to solve that problem later: there is a
bare copper wire connected to the metal box and to the outlet's green
screw, but it must be disconnected at the other end), BUT pressing the
outlet tester's GFCI Test button still trips the breaker. I thought that
a ground connection was necessary for the test button to work.

Perce

Percival P. Cassidy wrote:

I just replaced a regular outlet by a GFCI outlet. A GB outlet tester
with GFCI tester shows that there is no ground (just the same as before
I changed the outlet -- I'll try to solve that problem later: there is a
bare copper wire connected to the metal box and to the outlet's green
screw, but it must be disconnected at the other end), BUT pressing the
outlet tester's GFCI Test button still trips the breaker. I thought that
a ground connection was necessary for the test button to work.

Perce

Nope.

--
The e-mail address in our reply-to line is reversed in an attempt to
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CJT wrote:
Percival P. Cassidy wrote:

BUT pressing the outlet tester's GFCI Test button still trips the
breaker. I thought that a ground connection was necessary for the test
button to work.

Nope.

According to the diagrams here

http://www.codecheck.com/gfci_principal.htm

the test button diverts some current from hot to ground to cause the
hot/neutral conductors to not carry the same amount of current. Without
a ground, how would the test button work? Where does the diverted
current go?

Chris

Chris Friesen wrote:

According to the diagrams here

http://www.codecheck.com/gfci_principal.htm

the test button diverts some current from hot to ground to cause the
hot/neutral conductors to not carry the same amount of current. Without
a ground, how would the test button work? Where does the diverted
current go?

Doh...should learn to research first. Found an alternate design where
the test button diverts some current around the sensing toroid back to
neutral such that the toroid sees unbalanced current even though it is
actually balanced for the receptacle as a whole.

Works just fine with no real ground.

Chris

Could be grounded to such as the water pipes rather than the ground in
the main box.

Percival P. Cassidy wrote:
I just replaced a regular outlet by a GFCI outlet. A GB outlet tester
with GFCI tester shows that there is no ground (just the same as before
I changed the outlet -- I'll try to solve that problem later: there is a
bare copper wire connected to the metal box and to the outlet's green
screw, but it must be disconnected at the other end), BUT pressing the
outlet tester's GFCI Test button still trips the breaker. I thought that
a ground connection was necessary for the test button to work.

Perce

So when you push the test button on the outlet tester it trips? (or the
built-in GFCI test button?)

The external tester leaves out bypassing the toroid, I assume the GB
tester shorts hot-to-gnd through a resistor, so there must be enough of
a leakage current through the 'open' ground to trip the GFCI (as far as
I can reckon)

Dave

wrote in message
oups.com...

Percival P. Cassidy wrote:
I just replaced a regular outlet by a GFCI outlet. A GB outlet tester
with GFCI tester shows that there is no ground (just the same as before
I changed the outlet -- I'll try to solve that problem later: there is a
bare copper wire connected to the metal box and to the outlet's green
screw, but it must be disconnected at the other end), BUT pressing the
outlet tester's GFCI Test button still trips the breaker. I thought that
a ground connection was necessary for the test button to work.

Perce

So when you push the test button on the outlet tester it trips? (or the
built-in GFCI test button?)

The external tester leaves out bypassing the toroid, I assume the GB
tester shorts hot-to-gnd through a resistor, so there must be enough of
a leakage current through the 'open' ground to trip the GFCI (as far as
I can reckon)

I doubt that; if the tester shows an open ground there wouldn't be enough of
a connection to simulate a ground fault through the tester.
I would guess that the tester is wrong about the open ground. Has the OP
tested it on other outlets that are grounded?

Toller wrote:
wrote

The external tester leaves out bypassing the toroid, I assume the GB
tester shorts hot-to-gnd through a resistor, so there must be enough of
a leakage current through the 'open' ground to trip the GFCI (as far as
I can reckon)


I doubt that; if the tester shows an open ground there wouldn't be enough of
a connection to simulate a ground fault through the tester.
I would guess that the tester is wrong about the open ground. Has the OP
tested it on other outlets that are grounded?

See my other post. If the self-test shunts some current from hot to
neutral bypassing the toroid, you could have a self-test that works fine
while the external tester wouldn't be able to work due to a lack of a
ground path.

Chris

On Fri, 01 Dec 2006 15:04:56 -0500, "Percival P. Cassidy"
wrote:

I just replaced a regular outlet by a GFCI outlet. A GB outlet tester
with GFCI tester shows that there is no ground (just the same as before
I changed the outlet -- I'll try to solve that problem later: there is a
bare copper wire connected to the metal box and to the outlet's green
screw, but it must be disconnected at the other end), BUT pressing the
outlet tester's GFCI Test button still trips the breaker. I thought that
a ground connection was necessary for the test button to work.

Perce

Didn't we just play that game? You couldn't give it two days
before starting again?

Chris Friesen wrote:

CJT wrote:

Percival P. Cassidy wrote:


BUT pressing the outlet tester's GFCI Test button still trips the
breaker. I thought that a ground connection was necessary for the
test button to work.


Nope.


According to the diagrams here

http://www.codecheck.com/gfci_principal.htm

the test button diverts some current from hot to ground to cause the
hot/neutral conductors to not carry the same amount of current. Without
a ground, how would the test button work? Where does the diverted
current go?

Chris

Look at the diagrams again. The test button goes from hot to NEUTRAL
through a resistor.

--
The e-mail address in our reply-to line is reversed in an attempt to
minimize spam. Our true address is of the form .

On 12/01/06 04:14 pm Goedjn wrote:

I just replaced a regular outlet by a GFCI outlet. A GB outlet tester
with GFCI tester shows that there is no ground (just the same as before
I changed the outlet -- I'll try to solve that problem later: there is a
bare copper wire connected to the metal box and to the outlet's green
screw, but it must be disconnected at the other end), BUT pressing the
outlet tester's GFCI Test button still trips the breaker. I thought that
a ground connection was necessary for the test button to work.

Didn't we just play that game? You couldn't give it two days
before starting again?

No, we didn't. What I asked previously was about GFCI outlets or
breakers on an Edison circuit. This is not an Edison circuit.

Perce

Chris Friesen wrote:
Chris Friesen wrote:

According to the diagrams here

http://www.codecheck.com/gfci_principal.htm

the test button diverts some current from hot to ground to cause the
hot/neutral conductors to not carry the same amount of current.
Without a ground, how would the test button work? Where does the
diverted current go?

Doh...should learn to research first. Found an alternate design where
the test button diverts some current around the sensing toroid back to
neutral such that the toroid sees unbalanced current even though it is
actually balanced for the receptacle as a whole.

Works just fine with no real ground.

Chris

Chris
That scheme only applies to the built in test circuit in the GFCI
itself. A plug in tester does indeed need a ground in order to work but
the ground only has to be good enough to carry six milliamperes. That
would not make it a satisfactory low impedance pathway back to the
source via the main bonding jumper.
--
Tom Horne

"This alternating current stuff is just a fad. It is much too dangerous
for general use." Thomas Alva Edison

Tom Horne, Electrician wrote:

That scheme only applies to the built in test circuit in the GFCI
itself. A plug in tester does indeed need a ground in order to work but
the ground only has to be good enough to carry six milliamperes. That
would not make it a satisfactory low impedance pathway back to the
source via the main bonding jumper.

Yes, certainly.

Something that this whole discussion has prompted me to wonder...has
anyone ever heard of a tester (with a long heavy cable) that would plug
into the service panel directly that you could use to *really* test
outlets? Could be used to test non-grounded GFCIs, test for floating
ground, put 13A through each of the leads, measure voltage drop under
load, etc...? Seems like it might be useful to highlight possibly
sub-standard circuits.

Chris

On Fri, 01 Dec 2006 15:13:12 -0600, Chris Friesen
wrote:

Toller wrote:
wrote

The external tester leaves out bypassing the toroid, I assume the GB
tester shorts hot-to-gnd through a resistor, so there must be enough of
a leakage current through the 'open' ground to trip the GFCI (as far as
I can reckon)


I doubt that; if the tester shows an open ground there wouldn't be enough of
a connection to simulate a ground fault through the tester.
I would guess that the tester is wrong about the open ground. Has the OP
tested it on other outlets that are grounded?

See my other post. If the self-test shunts some current from hot to
neutral bypassing the toroid, you could have a self-test that works fine
while the external tester wouldn't be able to work due to a lack of a
ground path.

Chris

And the diagram appears to show this incorrectly. It shows both sides
of the resistor connecting to the LINE side of the transformer, when
you it needs to connect to one of each side. The real GFCI I looked at
did so.
--
24 days until the winter solstice celebration

Mark Lloyd
http://notstupid.laughingsquid.com

"Unlike biological evolution. 'intelligent design' is
not a genuine scientific theory and, therefore, has
no place in the curriculum of our nation's public
school classes." -- Ted Kennedy

Goedjn wrote:

On Fri, 01 Dec 2006 15:04:56 -0500, "Percival P. Cassidy"
wrote:


I just replaced a regular outlet by a GFCI outlet. A GB outlet tester
with GFCI tester shows that there is no ground (just the same as before
I changed the outlet -- I'll try to solve that problem later: there is a
bare copper wire connected to the metal box and to the outlet's green
screw, but it must be disconnected at the other end), BUT pressing the
outlet tester's GFCI Test button still trips the breaker. I thought that
a ground connection was necessary for the test button to work.

Perce


Didn't we just play that game? You couldn't give it two days
before starting again?


I promise to stay out of this one. G

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
The speed of light is 1.8*10^12 furlongs per fortnight.

Chris Friesen wrote:

Something that this whole discussion has prompted me to wonder...has
anyone ever heard of a tester (with a long heavy cable) that would plug
into the service panel directly that you could use to *really* test
outlets? Could be used to test non-grounded GFCIs, test for floating
ground, put 13A through each of the leads, measure voltage drop under
load, etc...? Seems like it might be useful to highlight possibly
sub-standard circuits.

Ecos Electronics made testers that used a current pulse to test circuit
grounds. Didn't need an external connection. Don't know if Ecos is
around anymore but the testers probably show up on eBay.

--
bud--

Chris Friesen wrote:
Tom Horne, Electrician wrote:

That scheme only applies to the built in test circuit in the GFCI
itself. A plug in tester does indeed need a ground in order to work
but the ground only has to be good enough to carry six milliamperes.
That would not make it a satisfactory low impedance pathway back to
the source via the main bonding jumper.

Yes, certainly.

Something that this whole discussion has prompted me to wonder...has
anyone ever heard of a tester (with a long heavy cable) that would plug
into the service panel directly that you could use to *really* test
outlets? Could be used to test non-grounded GFCIs, test for floating
ground, put 13A through each of the leads, measure voltage drop under
load, etc...? Seems like it might be useful to highlight possibly
sub-standard circuits.

Chris

The Ideal Suretest does that without a long cable.
--
Tom Horne

"This alternating current stuff is just a fad. It is much too dangerous
for general use." Thomas Alva Edison