Geoffrey S. Mendelson wrote:
Fred wrote:
I think many electrical fires could be stopped if GFCI were required on
all circuits....including faulty appliances that trip them.

AFCIs are the device intended to save the world. They trip on an arc of
about 5A (the old ones needed an arc more like 60A). For new wiring they
are generally required in a home when a GFCI is not required. The 2011
NEC may required AFCI protection when receptacles are replaced. They
also trip on a ground fault of about 30mA - not for protection of people.


Here in Israel they are required by the electric company BEFORE main breakers.

You can't get a new connection without one, and every few years there is
an advertising campaign to get people to install them in old homes.

We have 230 volt single phase service, and 230 volt 3 phase split into three
separate circuits, so we don't have the 120/240 problem in the US that
was previously discussed.


There are several systems for handling "ground" wires. The basic
interest is that "ground" wires essentially be at earth potential, and
that contact between a hot wire and ground trips a breaker.

In the US, the ground wire system is connected to earthing electrode(s)
at the building. This is likely the case in other countries as well.

The US also requires the neutral and ground be bonded at the service
disconnect. If there is a hot-to-ground short the path is ground wire to
service panel, G-N bond to neutral, service neutral back to the utility
transformer. This metal path produces a high current to trip the
breaker. The earth essentially plays no part because the resistance of
the earth path is far to high to trip a breaker.

The UK, from what I have read, has several ways to handle the "ground
system". One is to earth the neutral at the utility transformer, not
have a N-G bond at the building, and not run a ground wire with the hot
and neutral service wires. Ground faults would return through the earth
and not produce enough current to trip a breaker. I believe that these
systems require an RCD (trips on H-N current imbalance like a GFCI) as
the service breaker. The fault current through the earth does trip the
RCD. (The trip level is far higher than the 4-6mA for a GFCI.)

Could be what you have in Israel.

--
bud--

Fred wrote:

"Michael A. Terrell" wrote in
m:

That doesn't stop them from chewing on a cord, or getting hold of a
lamp they knocked off a table.



The 7ma current-to-ground trips the GFCI every time under your stretching
scenario for the ****ing contest. Yes, the kid would get an
instantaneous shock in the millisecond range, to no harm, but there's
plenty of leakage from hot to ground to trip the GFCI if he bites into a
wire, even if he's across the neutral. I've heard this BS
rationalization before trying to save money because they are expensive.
But, we tested it. We took an old metal 2-wire Porter-Cable electric
drill and ran a bright yellow wire from hot to the case of it....creating
the electrical fault. If you stayed totally insulated from ground, the
drill would run, but that damned GFCI was uncanny finding you out. Body
leakage to the air Xc would even trip it. If you stood in your sneakers
(insulated!) and touched the hot drill case, the GFCI tripped from the
capacitor your foot made with the concrete under the insulated sole. If
you started by touching NEUTRAL, THEN touching the hot drill motor, the
trip was instantaneous, and you barely could feel the shock DIRECTLY
ACROSS THE AC LINE before the GFCI tripped. Your idiot rationalization
with the little kid across the line wouldn't wash....especially if he was
sitting on a floor, even a wooden one with a vinyl top. (Click), dead
circuit, live kid.


Read furter upstream where they are a=talking about whole hhouse
GFI. That is the Eurropean name, used on 240 volt service. It doesn't
trip at 7 mA.


--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.

bud-- wrote:

Michael A. Terrell wrote:
tm wrote:
I agree with the GFI protection on all household outlets. Good idea.


No, it isn't. You can get nuisance trips on refrigerators and
freezers. They have grounded cords and they don't need GFCI. I haven't
seen a new copy of the NEC lately, but I was told it is against code in
the US to use a GFCI to power either.


It was never against the code to use GFCIs on refrigeration.

But the NEC used to have exceptions for GFCI requirements in garages and
basements where a refrigerator/freezer would be plugged in. Those
exceptions are gone.

Plug-in refrigerators/freezers using 15/20A 120V receptacles in
commercial kitchens are required to be on GFCI protected receptacles.

The UL allowed leakage for refrigerators/freezers is about 0.5mA.
Tripping a GFCI means the appliance has a problem.


Try to get someone to replace a refrigerator that trips a GFCI once
every six months.


--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.

On Feb 1, 6:22*pm, "Michael A. Terrell"
wrote:
bud-- wrote:

Michael A. Terrell wrote:
tm wrote:
I agree with the GFI protection on all household outlets. Good idea.

* *No, it isn't. *You can get nuisance trips on refrigerators and
freezers. *They have grounded cords and they don't need GFCI. *I haven't
seen a new copy of the NEC lately, but I was told it is against code in
the US to use a GFCI to power either.

It *was never against the code to use GFCIs on refrigeration.

But the NEC used to have exceptions for GFCI requirements in garages and
basements where a refrigerator/freezer would be plugged in. Those
exceptions are gone.

Plug-in refrigerators/freezers using 15/20A 120V receptacles in
commercial kitchens are required to be on GFCI protected receptacles.

The UL allowed leakage for refrigerators/freezers is about 0.5mA.
Tripping a GFCI means the appliance has a problem.

* *Try to get someone to replace a refrigerator that trips a GFCI once
every six months.

--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.- Hide quoted text -

- Show quoted text -

Well, I guess that I´m fortunate then. I live in a small appartment
and I have 4 outlets in my kitchen which are feed by two separate
circuits, with a dedicated circuit breaker for each one. Each circuit
is also protected by a GFCI. Each GFCI controls two outlets, including
the GFCI itself. In one of the circuits I have a refrigerator and a
microwave oven plugged in, and the GFCI has never tripped. I´m sure
the GFCI works because it trips when the test button is pressed
turning off everything plugged to it including the refrigerator outlet
which is wired to the output of the GFCI.

The refrigerator is an LG, less than six years old. I guess it is
pretty well insulated, both electrically and thermally.

Of course, I agree that an old fridge probably has enough leakage to
trip a GFCI given certain conditions, but I think that with newer
refrigerators that shouldn´t be an issue.

On Jan 30, 12:03*pm, mm wrote:
Is it possible to repair a whole house surge suppressor?

At 100 to 200 dollars, I don't want to keep buying new ones.

I was going to install a whole house surge suppressor. *When one of
them does its function, I think the MOV burns out, or some part does.

I haven't seen anything on the web about replacement modules for even
those units that might have them.

Will I be able to find, buy, and solder in replacement MOVs after the
first one burns out? (the green led goes out and the red led goes on)

I can't find any info about plug-in replacement parts, so if I can
repair any unit myself, I won't have to shop so thoroughly.

Items for sale, if interested:
I can install it myself. *I'm considering, in ascending price order:http://www.amazon.com/Intermatic-IG1...se-Surge-Suppr...

and less likely (plus two are required, one for each leg)http://www.amazon.com/Square-D-SDSA1.../dp/B002GUZ1NI

I think that repairing a whole house surge protector is like trying to
repair a circuit breaker. OK, technically it can be done, but there is
no way to reliabily test them for performance after the repair. For
instance, after opening a 20A circuit breaker to "fix it", there is no
way to be sure that the breaker will trip at their designated
ampacity. The same applies to a whole house surge protector... there
is no way to test it for reliability after the repair. Also, there is
the risk that the repaired protector catches fire when the time to
clamp a surge comes if it wasn´t properly repaired. To me trying to
save 100 or 200 US$ is no excuse for taking the risk of burning down a
whole house.

lsmartino wrote:

On Feb 1, 6:22 pm, "Michael A. Terrell"
wrote:
bud-- wrote:

Michael A. Terrell wrote:
tm wrote:
I agree with the GFI protection on all household outlets. Good idea.

No, it isn't. You can get nuisance trips on refrigerators and
freezers. They have grounded cords and they don't need GFCI. I haven't
seen a new copy of the NEC lately, but I was told it is against code in
the US to use a GFCI to power either.

It was never against the code to use GFCIs on refrigeration.

But the NEC used to have exceptions for GFCI requirements in garages and
basements where a refrigerator/freezer would be plugged in. Those
exceptions are gone.

Plug-in refrigerators/freezers using 15/20A 120V receptacles in
commercial kitchens are required to be on GFCI protected receptacles.

The UL allowed leakage for refrigerators/freezers is about 0.5mA.
Tripping a GFCI means the appliance has a problem.

Try to get someone to replace a refrigerator that trips a GFCI once
every six months.

--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.- Hide quoted text -

- Show quoted text -

Well, I guess that I´m fortunate then. I live in a small appartment
and I have 4 outlets in my kitchen which are feed by two separate
circuits, with a dedicated circuit breaker for each one. Each circuit
is also protected by a GFCI. Each GFCI controls two outlets, including
the GFCI itself. In one of the circuits I have a refrigerator and a
microwave oven plugged in, and the GFCI has never tripped. I´m sure
the GFCI works because it trips when the test button is pressed
turning off everything plugged to it including the refrigerator outlet
which is wired to the output of the GFCI.

The refrigerator is an LG, less than six years old. I guess it is
pretty well insulated, both electrically and thermally.

Of course, I agree that an old fridge probably has enough leakage to
trip a GFCI given certain conditions, but I think that with newer
refrigerators that shouldn´t be an issue.


Refigerators or freezers are reqired to be on a circuit by
themselves. A lot of older homes, or places that were enver inspected
didn't do this. I generally had three dedicated circuits to a kitchen,
and had the ceiling lights on a fourth, shared lighting only circuit.
If a refrigerator or similar appliance with a three wire cord is bad
enough to trip a GFCI, either it will stay at a low leakage, or quickly
reach a point to trip the breaker.

A lot of the leakage current comes from capacitance between the motor
windings, and the motor's core. New or old, this will always exist.
There is a lot higher risk of food posioning that electrocution from a
faulty refigerator or freezer.


--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.

Michael A. Terrell wrote:

Refigerators or freezers are reqired to be on a circuit by
themselves.

Not in the NEC.

Refigerators or freezers are reqired to be
on a circuit by themselves.

They aren't in my condo. And even a separate circuit doesn't keep the
transients from propagating to lines on the same phase.

bud-- wrote:

Michael A. Terrell wrote:

Refigerators or freezers are reqired to be on a circuit by
themselves.

Not in the NEC.


The NEC is the minimum code requirements. Every place I've lived
required it.


--
You can't fix stupid. You can't even put a band-aid on it, because it's
Teflon coated.