More GFCI wierdness

[patrick flowers]

Spooky - I'm beginning to think my coach is reading my email. I plugged
the 50A shore cable into a 20A adapter with a 16ga extension cord (not
trying to run the AC, just wanting to hook up a flourescent trouble
light). All this was plugged into a 20A outlet with GFCI protection.
You guessed it - the GFCI tripped.

While trouble shooting, I determined that the GFCI would hold with the
main breakers on, but as soon as any one of the four individual breakers
was turned on - it would trip. Got disgusted about the same time it got
dark. As far as I can tell, there's no AC load in the coach at all -
the water heater and the converter are out and the roof air and fridge
are off.

One of my planned summer projects was to extend a 220V circuit out to
the coach, but I'm halfway scared to until I find the ground fault.
More tomorrow.

Patrick
- --
Patrick Flowers
Mailtoatrick

The GMC Motorhome Page
http://www.gmcmotorhome.com

 

[john dolan]

>While trouble shooting, I determined that the GFCI would hold with the
>main breakers on, but as soon as any one of the four individual breakers
>was turned on - it would trip. Got disgusted about the same time it got
>dark. As far as I can tell, there's no AC load in the coach at all -
>the water heater and the converter are out and the roof air and fridge
>are off. Patrick

Could this not be a neutral to chassis ground fault that the second
sensor in the GFI is picking up. Turning off the branch breakers and
turning off the converter etc as you stated above takes any hot to
chassis ground faults out of the mix, but pulling each neutral
circuit wire at the neutral buss may be the only way to isolate this, as
Edgar discovered. (again you may have been saying the same thing, or you
may have been testing the net to see who has been following along. In
any case, even if I am wrong it, has been a good learning experience for
me)

Actually I would think (not having actually done it, myself) that it
would be faster to disconnect all neutrals and put them back one a time
till the GFI trips. (again trying not to tell you more than I know, but
please understand I am just learning about how these GFCI things really
work) I remember that you and several others have done breaker box
wiring and I have not, so if I have made an uninformed assumption please
understand I am just learning, and I am not assuming that you did not
consider this possibilty also.

But Patrick, before you disconnect all neutrals, I think I am getting a
weak signal from your GMC right now... I just went out in the back yard
and watered my ground... it's coming in stronger now, and I think your
GMC wants its neutral to ground... water heater circuit checked. Thank
God for Arch's grandfather.

Regards,
John

- --
"I do whatever my Rice Krispies tell me to..."
John said, from inside a 1974 Glacier on the
Potomac, just north of the White House.

 

[john dolan]

Patrick...

I hope you read your mail last to first, or at least read this before you
follow my suggestion to pull all your neutral wires.

I just learned that highly inductive loads...even flourescent lamps can
cause tripping of GFCIs. Maybe I am also learning why GMC only put
certain circuits on the GFCI. Try a trouble light like Arch's grandfather
used.

Regards,
John

- --
"I do whatever my Rice Krispies tell me to..."
John said, from inside a 1974 Glacier on the
Potomac, just north of the White House.

 

[john dolan]

>Spooky - I'm beginning to think my coach is reading my email. I plugged
>the 50A shore cable into a 20A adapter with a 16ga extension cord (not
>trying to run the AC, just wanting to hook up a flourescent trouble
>light). All this was plugged into a 20A outlet with GFCI protection.
>You guessed it - the GFCI tripped.

On a database of 2 units from my personal experience, both units (6 way
outlets) with surge protectors built-in tripped GFCI outlets over and
over again. Since they sell combination units (GFCI and Surge) the MOV
surge protection must be ahead of the GFCI unit rather than downstream
from it. Downstream is the case most of us run into when we plug our 6
way strip/surge outlet into a GFCI outlet.

Regards,
John

- --
"I do whatever my Rice Krispies tell me to..."
John said, from inside a 1974 Glacier on the
Potomac, just north of the White House.

 

[wayne newland]

John

Many years ago, I worked for the telephone co as a large system salesman.
While in a tech class, I heard about a lady who had to go to the hospital and
was in a real stew about not being home to water her telephone. Well as you
might expect some people thought she was crazy, but the real story was very
simple. When the installer had trouble finding a ground, he did the easy
thing...he drove a stake in the ground, attached the ground to it and told
the lady to water it every day or the bell wouldn't ring. And now you know
the rest of the story.

Wayne Newland F9300 75 Palm Beach

PS I just got back from helping The Washington Chiefs (World Champions of
the Minor Football League) win their league opener 21 - 0. In my spare time
I am their Trainer and my GMC goes to the games to carry my gear and be the
dressing room for the lovely cheerleaders. Eat your hearts out, guys. Oh,
well, someone has to do it.

> >While trouble shooting, I determined that the GFCI would hold with the
> >main breakers on, but as soon as any one of the four individual breakers
> >was turned on - it would trip. Got disgusted about the same time it got
> >dark. As far as I can tell, there's no AC load in the coach at all -
> >the water heater and the converter are out and the roof air and fridge
> >are off. Patrick
>
> Could this not be a neutral to chassis ground fault that the second
> sensor in the GFI is picking up. Turning off the branch breakers and
> turning off the converter etc as you stated above takes any hot to
> chassis ground faults out of the mix, but pulling each neutral
> circuit wire at the neutral buss may be the only way to isolate this, as
> Edgar discovered. (again you may have been saying the same thing, or you
> may have been testing the net to see who has been following along. In
> any case, even if I am wrong it, has been a good learning experience for
> me)
>
> Actually I would think (not having actually done it, myself) that it
> would be faster to disconnect all neutrals and put them back one a time
> till the GFI trips. (again trying not to tell you more than I know, but
> please understand I am just learning about how these GFCI things really
> work) I remember that you and several others have done breaker box
> wiring and I have not, so if I have made an uninformed assumption please
> understand I am just learning, and I am not assuming that you did not
> consider this possibilty also.
>
> But Patrick, before you disconnect all neutrals, I think I am getting a
> weak signal from your GMC right now... I just went out in the back yard
> and watered my ground... it's coming in stronger now, and I think your
> GMC wants its neutral to ground... water heater circuit checked. Thank
> God for Arch's grandfather.
>
> Regards,
> John
>
> --
> "I do whatever my Rice Krispies tell me to..."
> John said, from inside a 1974 Glacier on the
> Potomac, just north of the White House.