Hi and thanks for any help.
I just pulled out a standard outlet in our bathroom to replace with a
GFCI. Got the GFCI in fine. However, apparently the load side powers
our hallway's three way switch (which has there separate switches) and
then runs into a bedroom and provides lighting there.
Whenever I turn the hallway light on it trips the GFCI. The lights
farther down the line don't trip the switch, just the three-way
hallway lights. Is this expected or is there a problem with the
AIUI what actually trips a GFCI is an unbalance in the current
between the currents flowing through the live and neutral wires beyone
(downstream) of the GFCI. While agreeing that it is not necessary that
the lighting circuits be fed 'through' the GFCI, it would appear
advisable, instead of looking for a 'ground fault', to look for the
possibility of miswiring or at least an 'oddity' of the 3 way switch
No question bout it, and I think Bud probably nailed it. If there are
multiple circuits involved, sometimes neutrals from different circuits can
get tied together in multiple switch boxes, in fact I'm sure that I've
inadvertently done it myself. This would cause the GFCI to trip
Your electrician has incorrectly wired the 3 way switches. This
condition could cause the screw shell of the lamps to be hot under
One way to get help is pull the switches out and take pictures or pull
the switches out and assign each cable a number.
No it is not expected. It seems that there may be a problem with the
hallway lights. After you get it corrected you can remove the lighting feed
from the load side of the GFCI unless it is also protecting a shower light
or shower fan or another bath, garage, basement, or outdoor outlet.
I believe the NEC requires that the circuit serving a bathroom
receptacle either (1) serves only bathroom receptacles or (2) serves
only loads in that bathroom. So you need to run a new circuit for the
downstream loads, in addition to investigating how the downstream
loads are miswired.
It certainly wouldn't come into force. The guy decides, for his safety, to
install a GFCI where one didn't exist, and you think the NEC wouldn't allow
it unless he completely upgrades to current standards. That would be
Thanks a load for all the responses. As a temp fix to allow light in
the hallway I wired the load & line sides through the line side of the
GFCI. I'm not comfortable doing more than replacing outlets/switches
myself so I'll have an electrician out to determine the problem and
solution. I just wanted to know if it was something I should be
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