On 2008-07-10, Ralph Mowery wrote:

The refrigerator and freezer should not be on a GFIC. They can trip and the
food will spoil. This is one thing the nation electric code puts the food
first and safety second.

This is not quite true. In a residence a refrigerator need not be on
a GFCI receptacle. In a commerical kitchen, _all_ receptacles are
required to be GFCI. If a refrigerator trips a GFCI, it is defective.
Period. Now the defect, which is at least 6 ma of leakage current
between the hot and the ground, may not cause any other apparent
problems. But it is a defect none the less--an appliance should not
leak that much current to ground.

Cheers, Wayne

On Jul 11, 9:43*pm, Wayne Whitney wrote:
On 2008-07-10, Ralph Mowery wrote:

The refrigerator and freezer should not be on a GFIC. *They can trip and the
food will spoil. *This is one thing the nation electric code puts the food
first and safety second.

This is not quite true. *In a residence a refrigerator need not be on
a GFCI receptacle. *In a commerical kitchen, _all_ receptacles are
required to be GFCI. *If a refrigerator trips a GFCI, it is defective.
Period. *Now the defect, which is at least 6 ma of leakage current
between the hot and the ground, may not cause any other apparent
problems. *But it is a defect none the less--an appliance should not
leak that much current to ground.

Cheers, Wayne

Wayne-

I still not convinced about a frig tripping a GFI's proves that the
frig is bad.

Recent experience.......

small fan with two wire cord & all plastic construction (including
housing & fan on/off, two speed switch) mounted to a wooden window
frame.

Trips GFI about 50% of the time when switched quickly from high speed
to low speed and sometimes when switching off.

Where is the leakage to ground? Seems like something else is
happening.

oh, I tired the fan on four different GFI's ...trips on two of them
but never on the "other" two !?

Are the GFI's "bad" (and which ones?) or is the fan a problem?

At this point I'm stumped & I just cycle the switch more slowly and
never trip the GFI.

cheers
Bob

On Jul 12, 5:45*am, BobK207 wrote:
On Jul 11, 9:43*pm, Wayne Whitney wrote:

On 2008-07-10, Ralph Mowery wrote:

The refrigerator and freezer should not be on a GFIC. *They can trip and the
food will spoil. *This is one thing the nation electric code puts the food
first and safety second.

This is not quite true. *In a residence a refrigerator need not be on
a GFCI receptacle. *In a commerical kitchen, _all_ receptacles are
required to be GFCI. *If a refrigerator trips a GFCI, it is defective..
Period. *Now the defect, which is at least 6 ma of leakage current
between the hot and the ground, may not cause any other apparent
problems. *But it is a defect none the less--an appliance should not
leak that much current to ground.

Cheers, Wayne

Wayne-

I still not convinced about a frig tripping a *GFI's proves that the
frig is bad.

Recent experience.......

small fan with two wire cord & all plastic construction *(including
housing & fan on/off, two speed switch) *mounted to a wooden window
frame.

Trips GFI about 50% of the time when switched quickly from high speed
to low speed and sometimes *when switching off.

Where is the leakage to ground? * Seems like something else is
happening.

oh, I tired the fan on four different GFI's ...trips on two of them
but never on the "other" two !?

Are the GFI's "bad" * (and which ones?) * or is the fan a problem?

At this point I'm stumped & *I just cycle the switch more slowly and
never trip the GFI.

cheers
Bob


I agree. Most of us have seen similar things where somthing suddenly
switching on/off can trip some GFCIs. Not sure of the exact
mechanism, but for one thing, GFCIs do not trip based on leakage to
ground. They work by sensing and comparing the current flow in the
hot and neutral and tripping if the current is not equal. Apparently
there is something about larger inductive loads that can cause them to
trip.

Your example is an excellent one, because there clearly is no path to
ground.

On 2008-07-12, BobK207 wrote:

small fan with two wire cord & all plastic construction (including
housing & fan on/off, two speed switch) mounted to a wooden window
frame.

Trips GFI about 50% of the time when switched quickly from high speed
to low speed and sometimes when switching off.

Where is the leakage to ground? Seems like something else is
happening.

oh, I tired the fan on four different GFI's ...trips on two of them
but never on the "other" two !?

Are the GFI's "bad" (and which ones?) or is the fan a problem?

Good example. I guess the the fan shouldn't trip the the GFI--were
the two that tripped of recent vintage?

Cheers, Wayne

On Jul 12, 6:00*pm, Wayne Whitney wrote:
On 2008-07-12, BobK207 wrote:

small fan with two wire cord & all plastic construction *(including
housing & fan on/off, two speed switch) *mounted to a wooden window
frame.

Trips GFI about 50% of the time when switched quickly from high speed
to low speed and sometimes *when switching off.

Where is the leakage to ground? * Seems like something else is
happening.

oh, I tired the fan on four different GFI's ...trips on two of them
but never on the "other" two !?

Are the GFI's "bad" * (and which ones?) * or is the fan a problem?

Good example. *I guess the the fan shouldn't trip the the GFI--were
the two that tripped of recent vintage?

Cheers, Wayne

All four were recent installations.....within the last year.

All were identical models.

cheers
Bob