We are re-doing some electrical outlets and switches in our older home
(built 1954). We put a GFCI at the start of every branch. There is
one branch that keeps tripping the GFCI and I can't figure out why.
The wiring goes through the GFCI, to 4 other outlets, and through a
switch to this last outlet. we have determined that the switched
outlet is the problem.

We unplugged everything and turned the switch that controls the outlet
off. Then we turned the breaker on again, no trip. We plugged various

items into all of the other outlets, no trip. we turned on the light
that is controlled by the a different switch in the same box, no trip.
we turned the outlet on with the switch (nothing plugged in to it), no
trip. As soon as we plugged anything into it (we tried several items)
it would trip the GFCI every time. We tried having it plugged in and
then turning the switch on as well, still tripped. There is one red
wire coming into the outlet (hot from the switch) and two neutrals
coming out.


Can anyone point me in the right direction for what the problem might
be? Any help would be appreciated.


Thanks,
Steve

sfaust wrote:
it would trip the GFCI every time. We tried having it plugged in and
then turning the switch on as well, still tripped. There is one red
wire coming into the outlet (hot from the switch) and two neutrals
coming out.

NO! There are not two neutrals. There is one neutral and one ground.
GFCIs work by detecting when the current going through the hot lead
does not match the current coming back through the neutral lead.

It sounds like you have the neutral and ground reversed on the outlet
controlled by the switch. It's also possible the light you are plugging
in has some malfunctions. Is is a dimmer light?

Bill Ranck
Blacksburg, Va.

I really don't think it's a ground. Both wires are white insulated.
The outlets that we took out are ungrounded (2 prong) and I have not
seen any ground wires, that's part of the reason we're putting in the
GFCI's. Also, both of the white wires were connected to the side
terminals on the old outlets, there was no ground screw.

The light is not a dimmer. We will try it in another outlet with GFCI
protection to see if it trips it, we haven't tried that. I do think we
tried other electrical items in that outlet and got the same result
(GFCI trip).

I don't see how it could be a ground, but I'm by no means an expert
here, so if you still think it is please "splain" it a little more

thanks for the help,
Steve

On 15 Mar 2006 16:45:59 -0800, "sfaust" wrote:

I really don't think it's a ground. Both wires are white insulated.
The outlets that we took out are ungrounded (2 prong) and I have not
seen any ground wires, that's part of the reason we're putting in the
GFCI's. Also, both of the white wires were connected to the side
terminals on the old outlets, there was no ground screw.

The light is not a dimmer. We will try it in another outlet with GFCI
protection to see if it trips it, we haven't tried that. I do think we
tried other electrical items in that outlet and got the same result
(GFCI trip).

I don't see how it could be a ground, but I'm by no means an expert
here, so if you still think it is please "splain" it a little more

thanks for the help,
Steve

Look I'm definitely no electrical guru so bear with me but could the
GFCI be bad? I know I've heard of them going bad on occasion.

yeah, I thought that, but why would it work with the other outlets on
the system? It's fine as long as nothing is plugged into that last
outlet. It's not the GFCI that seems to be causing the problem. I
plugged the same lamp directly into the GFCI and it worked fine. I
also tried switching the problem outlet out for another one and that
didn't help, so as far as I can tell it would be somewhere in the
wiring?

Again, I'm pretty much a novice here with pretty basic electrical
knowledge, so if I'm missing something obvious or making a false
assumption please point it out because I probably don't see it

Thanks for helping,
Steve

On 15 Mar 2006 21:57:42 -0800, "sfaust" wrote:

yeah, I thought that, but why would it work with the other outlets on
the system? It's fine as long as nothing is plugged into that last
outlet. It's not the GFCI that seems to be causing the problem. I
plugged the same lamp directly into the GFCI and it worked fine. I
also tried switching the problem outlet out for another one and that
didn't help, so as far as I can tell it would be somewhere in the
wiring?

Again, I'm pretty much a novice here with pretty basic electrical
knowledge, so if I'm missing something obvious or making a false
assumption please point it out because I probably don't see it

Thanks for helping,
Steve


Ok, again just guesses on my part but it sounds to me like either the
wiring is wrong going into the switch from either side or at the last
outlet. I'd probably try switching one pair of wires at a time at
the switch and see what goes and then the last outlet. I say this
because it seems like your problem is from the switch to the last
outlet so I'm guessing it has to do with wiring. I can't say why tho
if you tell me it's been like that since the 50's but I don't have any
other guess and that seems to be the logical thing to do unless you
can come up with a better guess. If you exhaust all the combinations
of the above solution, then maybe try to leave the wiring as it was
and switch the wires in pairs at the GFCI.

If you do solve this problem, please report back so I can learn from
it (tho I don't own a home of that vintage currently). Good Luck.

sfaust wrote:
I really don't think it's a ground. Both wires are white insulated.
The outlets that we took out are ungrounded (2 prong) and I have not
seen any ground wires, that's part of the reason we're putting in the
GFCI's. Also, both of the white wires were connected to the side
terminals on the old outlets, there was no ground screw.

OK, if it is two white wires, where does the second one go?
There should be one coming from the switch location, not switched
but connected through that box. The other one must go somewhere.
I would try disconnecting each of those white wires, one at a time,
and see if it works with just one of them. The other is an
unknown. Is there another red or a black wire?

Bill Ranck
Blacksburg, Va.

Make sure that the neutral for the outlet is the
neutral that goes through the GFCI and and only through
the GFCI. What's with the "two white wires" that you
mentioned?


sfaust wrote:
yeah, I thought that, but why would it work with the other outlets on
the system? It's fine as long as nothing is plugged into that last
outlet. It's not the GFCI that seems to be causing the problem. I
plugged the same lamp directly into the GFCI and it worked fine. I
also tried switching the problem outlet out for another one and that
didn't help, so as far as I can tell it would be somewhere in the
wiring?

Again, I'm pretty much a novice here with pretty basic electrical
knowledge, so if I'm missing something obvious or making a false
assumption please point it out because I probably don't see it

Thanks for helping,
Steve

sfaust wrote:
Ok, after further investigation based on some info here, I have figured
it out. For any who are curious or are in the same situation here is
what happened:

Thanks for posting back. It's always nice to know that someone
got some useful help from a newsgroup.

Bill Ranck
Blacksburg, Va.