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Connecting GFCI to Two Lightswitches

4405 Views 12 Replies 4 Participants Last post by  mpoulton
I'm a little more than confused and hope you all can help me out!

I live in a old construction apartment complex that is wired using BX in Plaster and Cinder block walls. Having no previous outlet in the Bathroom, I knocked out the existing light-switch boxes and replaced them with a three gang steel masonry box.

There are three BX Cables coming into Box:
1x -- 3 Wire (Black, Red, White) This goes to Light 1
2x -- 2 Wire (Black, White) One goes to Light 2, and One provides Power from the Electrical Box.

The GCFI Outlet:
Pass & Seymour
1595-W
http://www.legrand.us/passandseymou...~/media/FB719ADBAAED4BAAA5813806B860C8AC.ashx

I took the 2 Wire and hooked it up to the GFCI. As a standalone outlet it works normally. When I add Light 1 to the GFCI, using its LOAD connections the GFCI Is tripping.

I've Included a detailed diagram of the incoming wiring, but am not sure where to go from here. Any help or guidance would be appreciated.

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I assume "light 1" is wired as a two-level fixture where the red and black wires each control part of the fixture? How do you have it connected exactly? The neutral for the light goes to the load-side neutral terminal on the GFCI, not to the line side, right?

Have you confirmed that there isn't actually a ground fault? The GFCI may just be doing it's job. A hot wire in contact with plaster or masonry may leak enough current to trip a GFCI. A hot wire touching metal lath certainly will.
mpoulton,

thanks for the reply. Light 1 is just a normal light fixture that goes above the sink. Light 2 is a hi-hat fixture that I dont use much. I believe the red serves as a hot wire.

The Ground is 12ga wire from the GFCI mounted to the Metal Masonry Box which is grounded by the BX cable. The GFCI doesn't trip until I try and hook up the lights, which I believed is caused by me wiring it incorrectly. How would I go about testing for a Ground Fault, I do have a MeterMan Handy.

I have an image of the original wiring below: This is how the wiring was when I opened up the box.

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Ah, looks like "light 1" is set up for a ceiling fan - the black wire in that cable is a constant-hot and would power the fan motor if a fan were installed.

First, how did you have this wired with the GFCI? A picture of that would be most useful.

Second, testing for a ground fault: Meterman makes a whole line of test equipment. What, specifically, do you have? The ideal tool to start with would be a sensitive clamp-on AC ammeter.
mpoulton,

thanks for the reply again.

Here is a picture of how I left it last night. I have to get another elbow from the store to connect Light 2 to the box properly.

Just an FYI, not sure if it matters, Some of the outlet's in the bedroom are down because the power to them, the chain, runs through the bathroom light switch box.

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Alright. So I think I've got it. Basically it is one of those thinking to hard situations, haha.

Alright so I originally was feeding the GFCI via a pigtail but it wasn't working. So I started to try and feed the switches through the GFCI via the LOAD connections and started to run into problems. I re-attached the Ground from the GFCI and pigtailed off the Hot wire to the GFCI and to the light switch and both work without tripping. I believe that I originally had wiring correct but overlooked securing the GFCI ground correctly on the receptacle, which when overlooked sent me in the wrong direction.
Why are you connecting the lighting to the GFCI load in the first place? A tripped GFCI will leave you in the dark. Secondly, using those right angle box connectors in an inaccessible location(buried in the wall) is a code violation.
Why wire the lights to the load side of the GFCI? Pigtail from the incoming wires to the lines side, connect everything else up just as it was.

FWIW, If you were trying to wire the GFCI as you left it in the last picture, it will trip every time... the neutrals to the lights and downstream outlets must be wired to the load terminal of the GFCI as well as the hots.

And the ground should have no bearing on the operation of the GFCI... it does not need one to operate.
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Why wire the lights to the load side of the GFCI? Pigtail from the incoming wires to the lines side, connect everything else up just as it was.

FWIW, If you were trying to wire the GFCI as you left it in the last picture, it will trip every time... the neutrals to the lights and downstream outlets must be wired to the load terminal of the GFCI as well as the hots.

And the ground should have no bearing on the operation of the GFCI... it does not need one to operate.
Agreed, I didn't catch the neutrals not connected to the load side. The box appears to be ungrounded as well.
Why wire the lights to the load side of the GFCI? Pigtail from the incoming wires to the lines side, connect everything else up just as it was.
Already done. See above post.

FWIW, If you were trying to wire the GFCI as you left it in the last picture, it will trip every time... the neutrals to the lights and downstream outlets must be wired to the load terminal of the GFCI as well as the hots.
That's done in the picture, maybe a bad angle doesn't allow that to be seen. I have the neutral pigtailed into the "Neutral Line Slot" of the GFCI.
Why are you connecting the lighting to the GFCI load in the first place? A tripped GFCI will leave you in the dark. Secondly, using those right angle box connectors in an inaccessible location(buried in the wall) is a code violation.
I figured that. I cannot move the cables as they are secured in the wall. What would allow me to attached the BX Cables to the Box without using Right Angle Connectors while not violating code?

Agreed, I didn't catch the neutrals not connected to the load side. The box appears to be ungrounded as well.
Correct me if I'm wrong, it's my understanding that the metal sleeve of the BX cable (armored) serves as the ground. Attaching a grounding cable screw to the metal box and a ground cable from the receptacle's ground screw to the box would create a ground...?

Why wire the lights to the load side of the GFCI? Pigtail from the incoming wires to the lines side, connect everything else up just as it was.
Already done. See above post.

FWIW, If you were trying to wire the GFCI as you left it in the last picture, it will trip every time... the neutrals to the lights and downstream outlets must be wired to the load terminal of the GFCI as well as the hots.
That's done in the picture, maybe a bad angle doesn't allow that to be seen. I have the neutral pigtailed into the "Neutral Line Slot" of the GFCI.
The supply neutral goes to the line neutral of the GFCI. The fixture neutrals go to the load side of the GFCI.
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That's done in the picture, maybe a bad angle doesn't allow that to be seen. I have the neutral pigtailed into the "Neutral Line Slot" of the GFCI.
No, it's definitely not right. All current that leaves the GFCI through the load-side hot terminal must also return to the GFCI through the load-side neutral terminal. So everything powered by the GFCI's load side must have its neutral connected ONLY to the GFCI's load-side neutral terminal. I can't tell exactly what you've got going on (doesn't look like anything is connected to the load side at all...) - but it's not right.
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