Went outside to add another electrical circuit at the BBQ and
discovered that all of my nice wire-tagging had faded to non-readable.

So I couldn't figure out which common went with which hot.

Then it dawned on me to simply trip the GFCIs which releases *both*
hots and commons so a simple ohm-meter check would do the trick.

NOT! Both GFCIs wouldn't trip when I pressed the test buttons :-(

Went to Radio Shack and bought a Receptacle/GFCI tester for $5.99.

At the same time I noticed a gadget to locate breakers... bought it
also ($29.95).

Went home and tested the GFCIs... both have failed :-( Tester was
verified on some indoor GFCIs... it would trip them.

Both bad units are outdoors, so maybe it was the heat (they both face
the western sun... it gets over 120°F here :-). Any other ideas about
why they fail?

The breaker locator is neat... plug a sender unit into an outlet, then
scan the breakers... works like a champ.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

Demonstrated is but another reason why homes require a
'whole house' surge protector on each incoming utility wire.
GFCIs are electronics that contain effective protection.
Protection that can be overwhelmed if incoming transients (ie
lightning) are not earthed before entering the building. IOW
GFCI failure is a symptom that a whole household of appliances
have ineffective protection. Maybe the home does not have the
proper central earth ground as well as no 'whole house'
protector. But GFCI failures can be created by incoming,
common mode transients. I have been told this type of failure
damages as many as 50% of all GFCIs in central FL.

$5+ for a GFCI tester? Its nothing more than a switch and
maybe a 15K resistor that connects hot (black) wire to safety
ground (green) wire. That same tester is what the TEST button
does - already inside the GFCI.

Jim Thompson wrote:
Went outside to add another electrical circuit at the BBQ and
discovered that all of my nice wire-tagging had faded to non-readable.

So I couldn't figure out which common went with which hot.

Then it dawned on me to simply trip the GFCIs which releases *both*
hots and commons so a simple ohm-meter check would do the trick.

NOT! Both GFCIs wouldn't trip when I pressed the test buttons :-(

Went to Radio Shack and bought a Receptacle/GFCI tester for $5.99.

At the same time I noticed a gadget to locate breakers... bought it
also ($29.95).

Went home and tested the GFCIs... both have failed :-( Tester was
verified on some indoor GFCIs... it would trip them.

Both bad units are outdoors, so maybe it was the heat (they both face
the western sun... it gets over 120°F here :-). Any other ideas about
why they fail?

The breaker locator is neat... plug a sender unit into an outlet, then
scan the breakers... works like a champ.

On Sat, 15 Nov 2003 18:35:43 -0500, w_tom wrote:

Demonstrated is but another reason why homes require a
'whole house' surge protector on each incoming utility wire.
GFCIs are electronics that contain effective protection.
Protection that can be overwhelmed if incoming transients (ie
lightning) are not earthed before entering the building. IOW
GFCI failure is a symptom that a whole household of appliances
have ineffective protection. Maybe the home does not have the
proper central earth ground as well as no 'whole house'
protector. But GFCI failures can be created by incoming,
common mode transients. I have been told this type of failure
damages as many as 50% of all GFCIs in central FL.

There *is* a whole-house surge-protector. All the GFCIs inside check
out OK, so I'm guessing it's a heat issue only.


$5+ for a GFCI tester? Its nothing more than a switch and
maybe a 15K resistor that connects hot (black) wire to safety
ground (green) wire. That same tester is what the TEST button
does - already inside the GFCI.


I earn $5.95 in less than 2 minutes designing ICs. I don't build
*anything* anymore except for fun or if the function is unavailable...
plus this tester also verifies phasing and no lost connections ;-)

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

"w_tom" wrote in message
...
Demonstrated is but another reason why homes require a
'whole house' surge protector on each incoming utility wire.
GFCIs are electronics that contain effective protection.
Protection that can be overwhelmed if incoming transients (ie
lightning) are not earthed before entering the building. IOW
GFCI failure is a symptom that a whole household of appliances
have ineffective protection. Maybe the home does not have the
proper central earth ground as well as no 'whole house'
protector. But GFCI failures can be created by incoming,
common mode transients. I have been told this type of failure
damages as many as 50% of all GFCIs in central FL.

$5+ for a GFCI tester? Its nothing more than a switch and
maybe a 15K resistor that connects hot (black) wire to safety
ground (green) wire. That same tester is what the TEST button
does - already inside the GFCI.



Not exactly the same. As I understand it the internal GFCI test switch will
work without a ground conductor connected because the connection is effected
between the hot conductor after the GFCI Device, and the Neutral before the
GFCI. The aftermarket testors wont trip the GFCI Device without a ground
conductor connected to it.

There are also usually indicators that allow some level of troubleshooting
as to the proper wiring of a receptacle.

Louis--
*********************************************
Remove the two fish in address to respond



Jim Thompson wrote:
Went outside to add another electrical circuit at the BBQ and
discovered that all of my nice wire-tagging had faded to non-readable.

So I couldn't figure out which common went with which hot.

Then it dawned on me to simply trip the GFCIs which releases *both*
hots and commons so a simple ohm-meter check would do the trick.

NOT! Both GFCIs wouldn't trip when I pressed the test buttons :-(

Went to Radio Shack and bought a Receptacle/GFCI tester for $5.99.

At the same time I noticed a gadget to locate breakers... bought it
also ($29.95).

Went home and tested the GFCIs... both have failed :-( Tester was
verified on some indoor GFCIs... it would trip them.

Both bad units are outdoors, so maybe it was the heat (they both face
the western sun... it gets over 120°F here :-). Any other ideas about
why they fail?

The breaker locator is neat... plug a sender unit into an outlet, then
scan the breakers... works like a champ.

Just because some GFCIs are working does not mean a surge
could not exist. These GFCIs are outside. Using buried
wire? IOW if the exterior (exterior) GFCI made a better earth
ground than the central earth ground for 'whole house'
protector, then surge would also use GFCI as a destructive
path to earth. If mounted on side of building, then this
scenario is not so likely.

Operating temperature for older versions GFCI chips is
typically up to 70 degrees C. Chip consumes near zero watts.
IOW heat is not a likely reason for failure for those type.
Have not seen datasheets for newer type GFCIs. But then is
that receptacle getting so warm that IC would exceed 70 degree
C?

How good (and short) that that ground for the 'whole house'
protector. Is there any good earthing path via those GFCIs?
Perhaps are those GFCIs located on the far side of the
building?


Jim Thompson wrote:
There *is* a whole-house surge-protector. All the GFCIs inside check
out OK, so I'm guessing it's a heat issue only.

On Sun, 16 Nov 2003 00:39:10 GMT, "Louis Bybee"
wrote:

"w_tom" wrote in message
...
Demonstrated is but another reason why homes require a
'whole house' surge protector on each incoming utility wire.
GFCIs are electronics that contain effective protection.
Protection that can be overwhelmed if incoming transients (ie
lightning) are not earthed before entering the building. IOW
GFCI failure is a symptom that a whole household of appliances
have ineffective protection. Maybe the home does not have the
proper central earth ground as well as no 'whole house'
protector. But GFCI failures can be created by incoming,
common mode transients. I have been told this type of failure
damages as many as 50% of all GFCIs in central FL.

$5+ for a GFCI tester? Its nothing more than a switch and
maybe a 15K resistor that connects hot (black) wire to safety
ground (green) wire. That same tester is what the TEST button
does - already inside the GFCI.



Not exactly the same. As I understand it the internal GFCI test switch will
work without a ground conductor connected because the connection is effected
between the hot conductor after the GFCI Device, and the Neutral before the
GFCI. The aftermarket testors wont trip the GFCI Device without a ground
conductor connected to it.



It will, the test button on a GFCI usually, through a resistor,
connects the GFCI protected hot to the unprotected neutral.

There are also usually indicators that allow some level of troubleshooting
as to the proper wiring of a receptacle.

Louis--
*********************************************
Remove the two fish in address to respond

w_tom wrote in message ...

Demonstrated is but another reason why homes require a
'whole house' surge protector on each incoming utility wire.
GFCIs are electronics that contain effective protection.
Protection that can be overwhelmed if incoming transients (ie
lightning) are not earthed before entering the building. IOW
GFCI failure is a symptom that a whole household of appliances
have ineffective protection. Maybe the home does not have the
proper central earth ground as well as no 'whole house'
protector. But GFCI failures can be created by incoming,
common mode transients. I have been told this type of failure
damages as many as 50% of all GFCIs in central FL.

Little surge protectors offer very little protection against
lightning. That is a common misconception.


$5+ for a GFCI tester? Its nothing more than a switch and
maybe a 15K resistor that connects hot (black) wire to safety
ground (green) wire. That same tester is what the TEST button
does - already inside the GFCI.

indeed.


Regards, NT

On Sat, 15 Nov 2003 15:44:40 -0700, Jim Thompson
wroth:


Both bad units are outdoors, so maybe it was the heat (they both face
the western sun... it gets over 120°F here :-). Any other ideas about
why they fail?

Are there both indoor and outdoor grade GFCI breakers available like
there are for ordinary receptacles?

Jim

"Jim Thompson" wrote in message
news
Went outside to add another electrical circuit at the BBQ and
discovered that all of my nice wire-tagging had faded to non-readable.

So I couldn't figure out which common went with which hot.

Then it dawned on me to simply trip the GFCIs which releases *both*
hots and commons so a simple ohm-meter check would do the trick.

NOT! Both GFCIs wouldn't trip when I pressed the test buttons :-(

Went to Radio Shack and bought a Receptacle/GFCI tester for $5.99.

At the same time I noticed a gadget to locate breakers... bought it
also ($29.95).

Went home and tested the GFCIs... both have failed :-( Tester was
verified on some indoor GFCIs... it would trip them.

Both bad units are outdoors, so maybe it was the heat (they both face
the western sun... it gets over 120°F here :-). Any other ideas about
why they fail?

Rip one apart and see what failed. They usually have screws on the back. All
they are is a current transformer with both the hot and the neutral going
through it. If the current in the neutral and the hot is not exactly the
same, a current is produced in the current transformer. Most GFI's trip at a
5 mA differential, meaning a 5 or more mA current leakage from the neutral
or hot will trip the GFI. Perhaps the solder joints failed from the excess
thermal cycling?

"Gary Tait" wrote in message
news
On Sun, 16 Nov 2003 00:39:10 GMT, "Louis Bybee"
wrote:

"w_tom" wrote in message
...
Demonstrated is but another reason why homes require a
'whole house' surge protector on each incoming utility wire.
GFCIs are electronics that contain effective protection.
Protection that can be overwhelmed if incoming transients (ie
lightning) are not earthed before entering the building. IOW
GFCI failure is a symptom that a whole household of appliances
have ineffective protection. Maybe the home does not have the
proper central earth ground as well as no 'whole house'
protector. But GFCI failures can be created by incoming,
common mode transients. I have been told this type of failure
damages as many as 50% of all GFCIs in central FL.

$5+ for a GFCI tester? Its nothing more than a switch and
maybe a 15K resistor that connects hot (black) wire to safety
ground (green) wire. That same tester is what the TEST button
does - already inside the GFCI.



Not exactly the same. As I understand it the internal GFCI test switch
will
work without a ground conductor connected because the connection is
effected
between the hot conductor after the GFCI Device, and the Neutral before
the
GFCI. The aftermarket testors wont trip the GFCI Device without a ground
conductor connected to it.



It will, the test button on a GFCI usually, through a resistor,
connects the GFCI protected hot to the unprotected neutral.



If you read my answer above, this is exactly what I indicated. In the second
part of my reply I suggested that an aftermarket tester (not the one on the
GFCI) wouldn't trip a GFCI where there wasn't a ground conductor connected
to it (try it).

Louis--
*********************************************
Remove the two fish in address to respond



There are also usually indicators that allow some level of
troubleshooting
as to the proper wiring of a receptacle.

Louis--
*********************************************
Remove the two fish in address to respond

On Sun, 16 Nov 2003 03:11:20 GMT, James Meyer
wrote:

On Sat, 15 Nov 2003 15:44:40 -0700, Jim Thompson
wroth:


Both bad units are outdoors, so maybe it was the heat (they both face
the western sun... it gets over 120°F here :-). Any other ideas about
why they fail?

Are there both indoor and outdoor grade GFCI breakers available like
there are for ordinary receptacles?

Jim

If you are asking about a breaker that fits in your panel, just about
all current styles have a GFCI breaker.

On Sun, 16 Nov 2003 02:10:40 -0500, Gary Tait
wroth:

On Sun, 16 Nov 2003 03:11:20 GMT, James Meyer
wrote:

On Sat, 15 Nov 2003 15:44:40 -0700, Jim Thompson
wroth:


Both bad units are outdoors, so maybe it was the heat (they both face
the western sun... it gets over 120°F here :-). Any other ideas about
why they fail?

Are there both indoor and outdoor grade GFCI breakers available like
there are for ordinary receptacles?

Jim

If you are asking about a breaker that fits in your panel, just about
all current styles have a GFCI breaker.

No. I was asking about the outlet receptacle type of GFCI.

But adding a single ground fault breaker per circuit to the panel would
seem to be a much better solution than adding multiple outlet type ground fault
breakers.

Jim

Most GFI's trip at a 5 mA
Jeff

That sounded too high, so I googled for confirmation. You're right.

When I worked in the hospital,
I remember the Electrical Safety Officer coming around with his cart
and checking every 110Vac gizmo. His spec was 15uA.
(You would marvel at this collection of cut-off molded 110V plugs.)

"JeffM" wrote in message
om...
Most GFI's trip at a 5 mA
Jeff

That sounded too high, so I googled for confirmation. You're right.

When I worked in the hospital,
I remember the Electrical Safety Officer coming around with his cart
and checking every 110Vac gizmo. His spec was 15uA.

Whoa! 15uA - Some insulation will collectively leak that at 120V AC
especially on a humid day, and then there's stray capacitance leaking to
ground!

(You would marvel at this collection of cut-off molded 110V plugs.)

"James Meyer" wrote in message
...
On Sun, 16 Nov 2003 02:10:40 -0500, Gary Tait

wroth:

On Sun, 16 Nov 2003 03:11:20 GMT, James Meyer
wrote:

On Sat, 15 Nov 2003 15:44:40 -0700, Jim Thompson

wroth:


Both bad units are outdoors, so maybe it was the heat (they both face
the western sun... it gets over 120°F here :-). Any other ideas about
why they fail?

Are there both indoor and outdoor grade GFCI breakers available like
there are for ordinary receptacles?

Jim

If you are asking about a breaker that fits in your panel, just about
all current styles have a GFCI breaker.

No. I was asking about the outlet receptacle type of GFCI.

But adding a single ground fault breaker per circuit to the panel would
seem to be a much better solution than adding multiple outlet type ground
fault
breakers.

Breakers are the best, however they generally cost 4 to 8 times as much, and
have the inconvenience of needing to go to the panel every time they trip
(and they can trip often when using power outside). The GFI plugs also have
terminals to wire additional plugs, lights, etc to protect things later on
in the circuit.


Jim

In (Jeff):
"JeffM" wrote in message
om...
Most GFI's trip at a 5 mA
Jeff

That sounded too high, so I googled for confirmation. You're right.

When I worked in the hospital,
I remember the Electrical Safety Officer coming around with his cart
and checking every 110Vac gizmo. His spec was 15uA.

Whoa! 15uA - Some insulation will collectively leak that at 120V AC
especially on a humid day, and then there's stray capacitance leaking to
ground!


Yeah but, in the desert southwest, there ain't much in the way of stray
humidity...

Jeff wrote:



Breakers are the best,

Why are breakers the best?

however they generally cost 4 to 8 times as much, and
have the inconvenience of needing to go to the panel every time they trip
(and they can trip often when using power outside). The GFI plugs also have
terminals to wire additional plugs, lights, etc to protect things later on
in the circuit.


Jim

James Meyer wrote:

On Sun, 16 Nov 2003 02:10:40 -0500, Gary Tait
wroth:

On Sun, 16 Nov 2003 03:11:20 GMT, James Meyer
wrote:

On Sat, 15 Nov 2003 15:44:40 -0700, Jim Thompson
wroth:


Both bad units are outdoors, so maybe it was the heat (they both face
the western sun... it gets over 120°F here :-). Any other ideas about
why they fail?

Are there both indoor and outdoor grade GFCI breakers available like
there are for ordinary receptacles?

Jim

If you are asking about a breaker that fits in your panel, just about
all current styles have a GFCI breaker.

No. I was asking about the outlet receptacle type of GFCI.

But adding a single ground fault breaker per circuit to the panel would
seem to be a much better solution than adding multiple outlet type ground fault
breakers.

A GFCI receptacle protects both itself and the circuit
connected to the load side of the receptacle.


Jim

Jim Thompson wrote:

Went outside to add another electrical circuit at the BBQ and
discovered that all of my nice wire-tagging had faded to non-readable.

So I couldn't figure out which common went with which hot.

Then it dawned on me to simply trip the GFCIs which releases *both*
hots and commons so a simple ohm-meter check would do the trick.

NOT! Both GFCIs wouldn't trip when I pressed the test buttons :-(

Went to Radio Shack and bought a Receptacle/GFCI tester for $5.99.

At the same time I noticed a gadget to locate breakers... bought it
also ($29.95).

Went home and tested the GFCIs... both have failed :-( Tester was
verified on some indoor GFCIs... it would trip them.

Both bad units are outdoors, so maybe it was the heat (they both face
the western sun... it gets over 120°F here :-). Any other ideas about
why they fail?

The breaker locator is neat... plug a sender unit into an outlet, then
scan the breakers... works like a champ.

...Jim Thompson

The environment, and lack of testing, kills GFCI receptacles
installed outdoors. GFCI receptacles should be tested once
a month, per manufacturer's instructions. They have two
general categories of failu electronic and mechanical.
Mechanical: the electronics operates a solenoid, which
operates the mechanical mechanism to open the contacts.
Heat/cold, humidity, dirt all can combine to gum up the
mechanical works - and that is particularly true outdoors
where there is more of all of those than indoors. When you
perform monthly testing, the mechanical mechanism is less
prone to freezing up due to the accumulation of gunk.
Electronic failure is also exacerbated by outdoor installation,
for the same three factors - heat/cold, humidity and dirt.
Heat harms electronics, temperature changes cause expansion/
contraction, humidity and dirt combine to form resistive
gunk.

Note that I did not mention surges. I do not mean to
say that a surge could not be involved - I just want
to exclude that from the environmental factors I am
talking about.

Install GFCI receptacles indoors to protect the outdoor
receptacles. It is a far better approach. The downside
is that a trip of the GFCI requires a walk inside to reset
it.

"Jeff" wrote in news:2yZtb.26920$R13.818487@ursa-
nb00s0.nbnet.nb.ca:


"JeffM" wrote in message
om...
Most GFI's trip at a 5 mA
Jeff

That sounded too high, so I googled for confirmation. You're right.

When I worked in the hospital,
I remember the Electrical Safety Officer coming around with his cart
and checking every 110Vac gizmo. His spec was 15uA.

Whoa! 15uA - Some insulation will collectively leak that at 120V AC
especially on a humid day, and then there's stray capacitance leaking
to
ground!

(You would marvel at this collection of cut-off molded 110V plugs.)



The 15ua spec is the limitation of leakage current to the patient, from
any piece of equipment. Not any sort of limitation for the GFCI device
itself. The spec at our hospital was 15 ua., but I think the spec was 10
ua in ICU & Surgery. The specs between the leakage current safety for
the patient and the amount of current necessary to trip a GFCI are
basically unrelated. The two were both safety factors but for two
different reasons. Even when an electrical device was grounded, there
could still be minute leakage currents, that could reach the patient.
These leakage currents had to be limited to below 10 or 15 microamps
because patients often had devices that made more intimate contact, with
the inside of the body. The skin does offer some resistance, however
even a range of microamps, could be fatal if connected internally.

I was a Biomedical Engineer/Safety engineer at a hospital for three
years. I had to test EVERY outlet and service almost every piece of
electrical/medical equipment in the hospital. The adjustable GFCI tester
I used was calibrated in ma and 99% on the GFCIs would trip as the knob
reached 3ma. They were click settings as opposed to a pot.

The first part of the input of the sensor for the GFCI was a toroid
transformer with three windings. The first two (I will call the main)
windings were wound as current opposing, around the toroid. Such that if
the two main windings(Hot & Neutral Lines) had the exact same amount of
current passing through them, they would cancel each other and no output
would be present at the third winding. The third winding was connected
to the differential inputs of an op-amp. If there was any imbalance of
current between the hot and neutral lines, the imbalance would negate the
cancellation and a current would be induced in the third winding of the
toroid, biasing the op-amp and in turn triggering the relay to break the
power circuit. The imbalance would be indicative of current taking an
inappropriate path to earth, through a path other than the neutral line
of that same outlet.

The statement that no safety ground line is required for the GFCI to
operate the way it was meant to, is true. However the test button would
not operate, because the test button put a resistor from the hot line, to
the safety ground line as a test, to cause the imbalance in the hot and
neutral lines. Even if no safety ground line was connected to the given
outlet, any amount of leakage above 2 or 3 ma, to another path to earth,
such as a waterpipe, would be measured, as an imbalance in the toroid
transformer, flip the output of the op-amp and in turn, trip the relay.
A safety ground is not necessary for a GFCI to operate normally, but of
course it would be stupid not to have a safety ground in any event.

buck

(this post was read in alt.binaries.schematics.electronics)

In sci.electronics.design Fred Abse wrote:
On Sat, 15 Nov 2003 20:18:15 -0500, Gary Tait wrote:

It will, the test button on a GFCI usually, through a resistor, connects
the GFCI protected hot to the unprotected neutral.

That's just the same as loading the circuit, it won't work. GFCIs monitor
current in *both* hot and neutral, which should be the same.

You need to create an imbalance current by introducing a resistance
between hot and *ground* 5mA might do it. 30mA _must_ do it, or the
protection is no damn good.

If you connect to the neutral (before the circuit) and to live (after),
then that works.

Ian Stirling wrote in
:

In sci.electronics.design Fred Abse
wrote:
On Sat, 15 Nov 2003 20:18:15 -0500, Gary Tait wrote:

It will, the test button on a GFCI usually, through a resistor,
connects the GFCI protected hot to the unprotected neutral.

That's just the same as loading the circuit, it won't work. GFCIs
monitor current in *both* hot and neutral, which should be the same.

You need to create an imbalance current by introducing a resistance
between hot and *ground* 5mA might do it. 30mA _must_ do it, or the
protection is no damn good.

If you connect to the neutral (before the circuit) and to live
(after), then that works.

Does the use of a GFCI outlet help in a situation where is circuit is
merely overloaded, but not short-circuited?

THX
Wayne

Good idea if only using theoretical knowledge. Bad in
reality. It is a classical example of why decisions based only
upon theory are not sufficient. It is why they teach in high
school science the concepts. Required is both the theoretical
concepts AND experiment confirmation. Why is the refrigerator,
specifically demanded by code, not on a GFCI? Because GFCIs
are good in some places and not desirable in others - as has
been proven by experience. A blown GFCI on a refrigerator can
create food poisoning - something learned by field
experiments.

wrote:
That is why the electric company should install a GFCI up on the
pole at the transformer. That way, everyone and everything is
protected in the whole neighborhood.

On Mon, 17 Nov 2003 13:11:30 GMT, Wayne Boatwright
wrote:

Ian Stirling wrote in
:

In sci.electronics.design Fred Abse
wrote:
On Sat, 15 Nov 2003 20:18:15 -0500, Gary Tait wrote:

It will, the test button on a GFCI usually, through a resistor,
connects the GFCI protected hot to the unprotected neutral.

That's just the same as loading the circuit, it won't work. GFCIs
monitor current in *both* hot and neutral, which should be the same.

You need to create an imbalance current by introducing a resistance
between hot and *ground* 5mA might do it. 30mA _must_ do it, or the
protection is no damn good.

If you connect to the neutral (before the circuit) and to live
(after), then that works.

Does the use of a GFCI outlet help in a situation where is circuit is
merely overloaded, but not short-circuited?

THX
Wayne

Help how? A GFCI provides no more voltage or current, or protection
against H-N overloads and short circuits.

On Mon, 17 Nov 2003 02:47:00 -0600, wrote:

On Sat, 15 Nov 2003 15:44:40 -0700, Jim Thompson
wrote:

Went outside to add another electrical circuit at the BBQ and
discovered that all of my nice wire-tagging had faded to non-readable.

So I couldn't figure out which common went with which hot.

Then it dawned on me to simply trip the GFCIs which releases *both*
hots and commons so a simple ohm-meter check would do the trick.

NOT! Both GFCIs wouldn't trip when I pressed the test buttons :-(

Went to Radio Shack and bought a Receptacle/GFCI tester for $5.99.

At the same time I noticed a gadget to locate breakers... bought it
also ($29.95).

Went home and tested the GFCIs... both have failed :-( Tester was
verified on some indoor GFCIs... it would trip them.

Both bad units are outdoors, so maybe it was the heat (they both face
the western sun... it gets over 120°F here :-). Any other ideas about
why they fail?

The breaker locator is neat... plug a sender unit into an outlet, then
scan the breakers... works like a champ.

...Jim Thompson


That is why the electric company should install a GFCI up on the pole
at the transformer. That way, everyone and everything is protected in
the whole neighborhood.

It would be incpnvenient to wait for the Poco to reset it. The best
thing would be a whole house GFCI, as is oftern used in most of the
rest of the world.

"Wayne Boatwright" wrote in message
. ..
Ian Stirling wrote in
:

In sci.electronics.design Fred Abse
wrote:
On Sat, 15 Nov 2003 20:18:15 -0500, Gary Tait wrote:

It will, the test button on a GFCI usually, through a resistor,
connects the GFCI protected hot to the unprotected neutral.

That's just the same as loading the circuit, it won't work. GFCIs
monitor current in *both* hot and neutral, which should be the same.

You need to create an imbalance current by introducing a resistance
between hot and *ground* 5mA might do it. 30mA _must_ do it, or the
protection is no damn good.

If you connect to the neutral (before the circuit) and to live
(after), then that works.

Does the use of a GFCI outlet help in a situation where is circuit is
merely overloaded, but not short-circuited?

THX
Wayne

The circuitry internal to a GFCI Device is specifically designed to sense,
and trip, in the event of an imbalance in the current flow between the
current carrying conductors (the current in one has to be within 4 to 6 ma
of the current in the other), the Hot and the Neutral (120v), or Hot and Hot
(208 - 240v USA). As long as the current is balanced it makes no difference
to the GFCI Device if it is overloaded, or shorted between the current
carrying conductors. If there is no imbalance, the GFCI Device is unlikely
to trip even in the event of a direct short between the current carrying
conductors unless a portion of the current finds a path other than the
intended one.

Louis--
*********************************************
Remove the two fish in address to respond

Went outside to add another electrical circuit at the BBQ and
discovered that all of my nice wire-tagging had faded to non-readable.

Didn't you use the appropriate colored wires?

And as to why they didn't last you don't give us enough details.
There are different grades of receptacles. Plus being put outdoors
certainly does not help. I have no idea how good the housing is and
if it leaks. Plus I have no idea if the GFCI's that broke were cheap
ones made in China.

On 17 Nov 2003 12:22:31 -0800, (Childfree
Scott) wrote:

Went outside to add another electrical circuit at the BBQ and
discovered that all of my nice wire-tagging had faded to non-readable.

Didn't you use the appropriate colored wires?

And as to why they didn't last you don't give us enough details.
There are different grades of receptacles. Plus being put outdoors
certainly does not help. I have no idea how good the housing is and
if it leaks. Plus I have no idea if the GFCI's that broke were cheap
ones made in China.

Two circuits, each common is white. Have to be paired correctly thru
the GFCI.

Housing is standard metal outdoor/wet-location box.

Malaysia. The new ones are made in Mexico :-(

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

On 17 Nov 2003 12:22:31 -0800, (Childfree
Scott) wrote:

Went outside to add another electrical circuit at the BBQ and
discovered that all of my nice wire-tagging had faded to non-readable.

Didn't you use the appropriate colored wires?

And as to why they didn't last you don't give us enough details.
There are different grades of receptacles. Plus being put outdoors
certainly does not help. I have no idea how good the housing is and
if it leaks. Plus I have no idea if the GFCI's that broke were cheap
ones made in China.

Should have also noted: The wiring in question was pre-placed for
expansion and capped off with wire nuts. So now I have to pair off
the black and red with the proper white, otherwise the GFCIs will trip
on any load.

...Jim Thompson
--
| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC's and Discrete Systems | manus |
| Phoenix, Arizona Voice480)460-2350 | |
| E-mail Address at Website Fax480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |

I love to cook with wine. Sometimes I even put it in the food.

Gary Tait wrote:

On Mon, 17 Nov 2003 02:47:00 -0600, wrote:

On Sat, 15 Nov 2003 15:44:40 -0700, Jim Thompson
wrote:

Went outside to add another electrical circuit at the BBQ and
discovered that all of my nice wire-tagging had faded to non-readable.

So I couldn't figure out which common went with which hot.

Then it dawned on me to simply trip the GFCIs which releases *both*
hots and commons so a simple ohm-meter check would do the trick.

NOT! Both GFCIs wouldn't trip when I pressed the test buttons :-(

Went to Radio Shack and bought a Receptacle/GFCI tester for $5.99.

At the same time I noticed a gadget to locate breakers... bought it
also ($29.95).

Went home and tested the GFCIs... both have failed :-( Tester was
verified on some indoor GFCIs... it would trip them.

Both bad units are outdoors, so maybe it was the heat (they both face
the western sun... it gets over 120°F here :-). Any other ideas about
why they fail?

The breaker locator is neat... plug a sender unit into an outlet, then
scan the breakers... works like a champ.

...Jim Thompson


That is why the electric company should install a GFCI up on the pole
at the transformer. That way, everyone and everything is protected in
the whole neighborhood.

It would be inconvenient to wait for the Poco to reset it. The best
thing would be a whole house GFCI, as is oftern used in most of the
rest of the world.

So something minor happens, and all the lights go off? THIS IS A VERY
STUPID IDEA. The code here requires separate lighting and receptacle
circuits so the room doesn't go dark if you trip a breaker. Also, most
areas of a home do not need GFCI protection. Wet areas, areas with bare
concrete floors, or outdoors make sense. Some circuits it is illegal to
use a GFCI breaker, like a refrigerator, or a freezer.
--


Michael A. Terrell
Central Florida

wrote in message
...


Jeff wrote:



Breakers are the best,

Why are breakers the best?

Because GFI breakers are at the panel, and all wiring, outlets, accessories,
etc are protected, not just the ones after the GFI outlet. GFI breakers
should be more reliable, especially since they are in a usually fairly
controlled environment. GFI breakers are also located in one spot - if a GFI
plug trips from an outlet later on in the circuit, then there may be some
difficulty in locating which GFI outlet tripped, or if a normal breaker
tripped from over current.


however they generally cost 4 to 8 times as much, and
have the inconvenience of needing to go to the panel every time they
trip
(and they can trip often when using power outside). The GFI plugs also
have
terminals to wire additional plugs, lights, etc to protect things later
on
in the circuit.


Jim

In (Michael A. Terrell):
Gary Tait wrote:

On Mon, 17 Nov 2003 02:47:00 -0600, wrote:

On Sat, 15 Nov 2003 15:44:40 -0700, Jim Thompson
wrote:

Went outside to add another electrical circuit at the BBQ and
discovered that all of my nice wire-tagging had faded to
non-readable.

So I couldn't figure out which common went with which hot.

Then it dawned on me to simply trip the GFCIs which releases *both*
hots and commons so a simple ohm-meter check would do the trick.

NOT! Both GFCIs wouldn't trip when I pressed the test buttons :-(

Went to Radio Shack and bought a Receptacle/GFCI tester for $5.99.

At the same time I noticed a gadget to locate breakers... bought it
also ($29.95).

Went home and tested the GFCIs... both have failed :-( Tester was
verified on some indoor GFCIs... it would trip them.

Both bad units are outdoors, so maybe it was the heat (they both face
the western sun... it gets over 120°F here :-). Any other ideas
about why they fail?

The breaker locator is neat... plug a sender unit into an outlet,
then scan the breakers... works like a champ.

...Jim Thompson


That is why the electric company should install a GFCI up on the pole
at the transformer. That way, everyone and everything is protected in
the whole neighborhood.

It would be inconvenient to wait for the Poco to reset it. The best
thing would be a whole house GFCI, as is oftern used in most of the
rest of the world.

So something minor happens, and all the lights go off? THIS IS A VERY
STUPID IDEA. The code here requires separate lighting and receptacle
circuits so the room doesn't go dark if you trip a breaker. Also, most
areas of a home do not need GFCI protection. Wet areas, areas with bare
concrete floors, or outdoors make sense. Some circuits it is illegal to
use a GFCI breaker, like a refrigerator, or a freezer.


Really. If we have to ground-fault an entire house (because the occupants
are too stupid and keep getting electrocuted to death) then maybe they
should just go live in a hut somewhere in Afghanistan, where there is little
risk of electrocution?

In (Mark Jones):
In (Michael A. Terrell):
Gary Tait wrote:

On Mon, 17 Nov 2003 02:47:00 -0600, wrote:

On Sat, 15 Nov 2003 15:44:40 -0700, Jim Thompson
wrote:

Went outside to add another electrical circuit at the BBQ and
discovered that all of my nice wire-tagging had faded to
non-readable.

So I couldn't figure out which common went with which hot.

Then it dawned on me to simply trip the GFCIs which releases *both*
hots and commons so a simple ohm-meter check would do the trick.

NOT! Both GFCIs wouldn't trip when I pressed the test buttons :-(

Went to Radio Shack and bought a Receptacle/GFCI tester for $5.99.

At the same time I noticed a gadget to locate breakers... bought it
also ($29.95).

Went home and tested the GFCIs... both have failed :-( Tester was
verified on some indoor GFCIs... it would trip them.

Both bad units are outdoors, so maybe it was the heat (they both
face the western sun... it gets over 120°F here :-). Any other
ideas about why they fail?

The breaker locator is neat... plug a sender unit into an outlet,
then scan the breakers... works like a champ.

...Jim Thompson


That is why the electric company should install a GFCI up on the pole
at the transformer. That way, everyone and everything is protected
in the whole neighborhood.

It would be inconvenient to wait for the Poco to reset it. The best
thing would be a whole house GFCI, as is oftern used in most of the
rest of the world.

So something minor happens, and all the lights go off? THIS IS A
VERY STUPID IDEA. The code here requires separate lighting and
receptacle circuits so the room doesn't go dark if you trip a breaker.
Also, most areas of a home do not need GFCI protection. Wet areas,
areas with bare concrete floors, or outdoors make sense. Some circuits
it is illegal to use a GFCI breaker, like a refrigerator, or a freezer.


Really. If we have to ground-fault an entire house (because the
occupants are too stupid and keep getting electrocuted to death) then
maybe they should just go live in a hut somewhere in Afghanistan, where
there is little risk of electrocution?


Speaking of electrocution, I got quite a nasty zap from my plasma cutter
the other day. 380VAC/20A plasma arc (open circuit), ground clamp wasn't
getting sufficient contact with rusty metal. That was with rubber soled
shoes (no steel toe), apron, and thick leather welding gloves. Anyone got a
GFCI for that baby?

It would be incpnvenient to wait for the Poco to reset it. The best
thing would be a whole house GFCI, as is oftern used in most of the
rest of the world.

Whole house GFI? Where is this "rest of the world"? GFI'ing a whole house
would be stupid.

Mark Jones wrote:

In (Mark Jones):
In (Michael A. Terrell):
Gary Tait wrote:

On Mon, 17 Nov 2003 02:47:00 -0600, wrote:

On Sat, 15 Nov 2003 15:44:40 -0700, Jim Thompson
wrote:

Went outside to add another electrical circuit at the BBQ and
discovered that all of my nice wire-tagging had faded to
non-readable.

So I couldn't figure out which common went with which hot.

Then it dawned on me to simply trip the GFCIs which releases *both*
hots and commons so a simple ohm-meter check would do the trick.

NOT! Both GFCIs wouldn't trip when I pressed the test buttons :-(

Went to Radio Shack and bought a Receptacle/GFCI tester for $5.99.

At the same time I noticed a gadget to locate breakers... bought it
also ($29.95).

Went home and tested the GFCIs... both have failed :-( Tester was
verified on some indoor GFCIs... it would trip them.

Both bad units are outdoors, so maybe it was the heat (they both
face the western sun... it gets over 120°F here :-). Any other
ideas about why they fail?

The breaker locator is neat... plug a sender unit into an outlet,
then scan the breakers... works like a champ.

...Jim Thompson


That is why the electric company should install a GFCI up on the pole
at the transformer. That way, everyone and everything is protected
in the whole neighborhood.

It would be inconvenient to wait for the Poco to reset it. The best
thing would be a whole house GFCI, as is oftern used in most of the
rest of the world.

So something minor happens, and all the lights go off? THIS IS A
VERY STUPID IDEA. The code here requires separate lighting and
receptacle circuits so the room doesn't go dark if you trip a breaker.
Also, most areas of a home do not need GFCI protection. Wet areas,
areas with bare concrete floors, or outdoors make sense. Some circuits
it is illegal to use a GFCI breaker, like a refrigerator, or a freezer.


Really. If we have to ground-fault an entire house (because the
occupants are too stupid and keep getting electrocuted to death) then
maybe they should just go live in a hut somewhere in Afghanistan, where
there is little risk of electrocution?

Speaking of electrocution, I got quite a nasty zap from my plasma cutter
the other day. 380VAC/20A plasma arc (open circuit), ground clamp wasn't
getting sufficient contact with rusty metal. That was with rubber soled
shoes (no steel toe), apron, and thick leather welding gloves. Anyone got a
GFCI for that baby?

No, but I have a suggestion. A second ground clip, connected to a low
voltage power supply, and a relay with a low voltage, high current coil.
Then use the relay contacts to make sure that both clamps are making
good contact, the plasma cutter doesn't fire up. The second clamp
wouldn't have to be as heavy as the ground clamp, and you might even
mount them together, so you put them on the metal like they were a
single clamp.
--


Michael A. Terrell
Central Florida

On Mon, 17 Nov 2003 13:11:30 GMT, Wayne Boatwright
wrote:

Does the use of a GFCI outlet help in a situation where is circuit is
merely overloaded, but not short-circuited?

THX
Wayne

No. A GFCI is not an overcurrent protection device - it just protects
against leakage current as indicated by a difference between supply
and return currents in the circuit.



--
Peter Bennett, VE7CEI
new newsgroup users info : http://vancouver-webpages.com/nnq
GPS and NMEA info: http://vancouver-webpages.com/peter
Vancouver Power Squadron: http://vancouver.powersquadron.ca

Michael A. Terrell wrote:
So something minor happens, and all the lights go off? THIS IS A
VERY STUPID IDEA.

A ground fault is not something i would consider minor. I'd rather be
inconvinienced(sp?) by having to go to the box and reset the gfi than get
shocked by faulty equipment.
You can have a fault anywhere and on any electrical device on the house, why
limit protection ?

The code here requires separate lighting and
receptacle circuits so the room doesn't go dark if you trip a
breaker.

We have that too. Different breakers for lighting and receptacles.

More info: country is Portugal, Here we have the meter, followed by a big
breaker that is also a GFI (which we call "differential breaker") outside
the house/apartment, the differential fault current is 500mA and overcurrent
is settable from 10 to 30 Amps, according to hired power.
Then, inside the house there is the main panel with a smaller breaker/gfi
that feeds all the circuit breakers. Mine is 30mA, way too high, in my
experience. Lights and receptacles have to be on different circuits. Power
is 3 phase at least for most houses, i'm not sure about apartments.


circuits it is illegal to use a GFCI breaker, like a refrigerator, or
a freezer.

Why?

--
Steve Sous

Steve Sousa wrote:

Michael A. Terrell wrote:
So something minor happens, and all the lights go off? THIS IS A
VERY STUPID IDEA.

A ground fault is not something i would consider minor. I'd rather be
inconvinienced(sp?) by having to go to the box and reset the gfi than get
shocked by faulty equipment.
You can have a fault anywhere and on any electrical device on the house, why
limit protection ?

You don't need to shut down the whole house for one fault.

The code here requires separate lighting and
receptacle circuits so the room doesn't go dark if you trip a
breaker.

We have that too. Different breakers for lighting and receptacles.

More info: country is Portugal, Here we have the meter, followed by a big
breaker that is also a GFI (which we call "differential breaker") outside
the house/apartment, the differential fault current is 500mA and overcurrent
is settable from 10 to 30 Amps, according to hired power.
Then, inside the house there is the main panel with a smaller breaker/gfi
that feeds all the circuit breakers. Mine is 30mA, way too high, in my
experience. Lights and receptacles have to be on different circuits. Power
is 3 phase at least for most houses, i'm not sure about apartments.

In the US we have individual GFCI breakers, or outlets, so you can
protect any area without killing everything in the house. I prefer our
method. Especially when I am working out in my shop after dark. I have
trouble walking, and I would have to wait till daylight peeked into the
air vents along the roof so i could see well enough to make my way out
of a metal building with no windows.


circuits it is illegal to use a GFCI breaker, like a refrigerator, or
a freezer.

Why?

Do you like to eat spoiled food? What happens if you are gone for a
couple days and that GFI trips? with no one home to notice, you have a
big mess to clean up, not to mention the cost of replacing all the food.
--


Michael A. Terrell
Central Florida

Peter Bennett wrote in
news.com:

On Mon, 17 Nov 2003 13:11:30 GMT, Wayne Boatwright
wrote:

Does the use of a GFCI outlet help in a situation where is circuit is
merely overloaded, but not short-circuited?

THX
Wayne

No. A GFCI is not an overcurrent protection device - it just protects
against leakage current as indicated by a difference between supply
and return currents in the circuit.




Thank you...

Wayne

"Louis Bybee" wrote in
news:QO9ub.28242$Dw6.139682@attbi_s02:

"Wayne Boatwright" wrote in message
. ..
Ian Stirling wrote in
:

In sci.electronics.design Fred Abse
wrote:
On Sat, 15 Nov 2003 20:18:15 -0500, Gary Tait wrote:

It will, the test button on a GFCI usually, through a resistor,
connects the GFCI protected hot to the unprotected neutral.

That's just the same as loading the circuit, it won't work. GFCIs
monitor current in *both* hot and neutral, which should be the
same.

You need to create an imbalance current by introducing a
resistance between hot and *ground* 5mA might do it. 30mA _must_
do it, or the protection is no damn good.

If you connect to the neutral (before the circuit) and to live
(after), then that works.

Does the use of a GFCI outlet help in a situation where is circuit is
merely overloaded, but not short-circuited?

THX
Wayne

The circuitry internal to a GFCI Device is specifically designed to
sense, and trip, in the event of an imbalance in the current flow
between the current carrying conductors (the current in one has to be
within 4 to 6 ma of the current in the other), the Hot and the Neutral
(120v), or Hot and Hot (208 - 240v USA). As long as the current is
balanced it makes no difference to the GFCI Device if it is
overloaded, or shorted between the current carrying conductors. If
there is no imbalance, the GFCI Device is unlikely to trip even in the
event of a direct short between the current carrying conductors unless
a portion of the current finds a path other than the intended one.

Louis--
*********************************************
Remove the two fish in address to respond



Thank you...

Wayne