Mike;

Suggest you try a better grade of cord. There are low leakage outdoor rated cords
available. Cord leakage should be in the uA (10E-6) range. Make sure the cord is
water resistant, the words "Water-Resistant" should be printed every foot or so on
the jacket. Make sure also that the jacket is UV rated for outdoor use. UV can
begin to breakdown the jacket on cable very quickly, which then allows moisture to
intrude, and moisture will increase the leakage current. I have seen cheep orange
"outdoor" cords have ordinary lamp cord inside. Make sure the cord is UL rated for
Outdoors.

Sometimes a cord with larger conductors, smaller wire guage. IE> going from 18 AWG
to 16 AWG will sometimes help. And make sure it is a three wire cord.

By the way, I am an engineer and I make my own cords!

Paul




Michael Smith wrote:

> Oftentimes, natural leakage thru the insulation of a long extension cord
> (read 50-100+ feet) or from a long inside-the-wall run to another outlet
> is enough to trip a GFCI (Ground Fault Circuit Interrupter). A GFCI
> works by "sensing" the current running thru the hot and neutral lines
> and comparing them. If the difference between the two is >5 ma
> (milliamp=1/1000 of an amp), GFCI's are supposed to trip. For example,
> if you are vacuuuming the car, there might be, say, 5 amps going down
> the hot line and 5 amps coming back up the neutral (I know, not exact,
> but for brevity's sake). This is normal. Say you step in a puddle
> while turning the vac off. Now, 5 amps might be running thru the hot
> line, but since you offer less resistance to the current than the
> vacuum's motor, that current is going to pass thru you into ground
> instead of going back up the neutral line of the cord. The current thru
> both wires is not equal now. The GFCI trips, hopefully in such a quick
> time that the 5 amps runs thru you for a *very* tiny moment. The real
> problem arises when there is a long run between the line (the GFCI) and
> the load (telescope, light, weedeater, vacuum). Insulation isn't
> absolutely insulative (is that a word?). There is always a small
> leakage from the hot line to ground (the actual "ground" wire, the outer
> insulation, the ground itself, whatever.) On a long run, this leakage
> can accumulate to a large enough amount to cause a properly working GFCI
> to trip needlessly. I have seen this happen many times. I have even
> seen a GFCI trip with 250' of extension cord plugged in and nothing
> else.
>
> Mike
>
> I am not an electrician...however, is seems nobody has told the rest of
> my family.
>
> James W. Burrows wrote:
> >
> > At 15:59 1998-10-30 -0500, M. Gartland wrote:
> >
> > >Here is a story......for some strange reason my "new" coffee maker would not
> > >work one morning, it had not been making very tasty cups of coffee since it
> > >was bought so I was already pissed off about it.
> > <snip>
> >
> > I've had experience with a GFCI that was too sensitive, or just no good.
> > I'd installed it down in the basement to power the clothes washer (and, via
> > extension cord, the LX200). The d**n thing was _always_ tripped. Ripped
> > washer apart, found a few chaffed wires, taped them up, felt proud of
> > myself, but it still tripped. Installed an outlet on the power side of the
> > GFCI for the washer, but felt guilty. I thought, hmmm, wonder if that GFCI
> > is no good (made in China), replaced it with a Levicon (made in Mexico) -
> > solved! The new one tests OK, doesn't trip, and the washer's back on it.
> >
> > -- Jim Burrows phone 206.244.2933, fax .0294
> > -- Seattle N47.4722, W122.3661 (WGS84)

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