Home>Discussions>ELECTRICAL & LIGHTING>What to do with neutral wire?
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scott180
What to do with neutral wire?

I'm looking to rewire the three way switches that control the light at the top of the basement stairs and the two lights in the finished basement. Currently the power comes in at the light and is routed down to the switch at the top of the stairs. The switch at the bottom of the stairs is extended off the top switch box. Power is also extended from the top switch to the lights in the basement.

The issue is that the lights are tied into the same circuit as the living room. When the previous owner remodeled, he left it that way when he added the new basement lighting. I need to move it to a new circuit because we keep blowing the breaker. I can pull power to the lower switch and cap the power coming in at the light fixture.

I have all the wiring figured out except for one thing. The wire I have to add from the bottom switch to connect the switched power to the basement lights would have a floating neutral. Not sure if I should let both ends float or tie it off to something. I can tie one end to neutral in a junction box. But if I do that, should the other end float or be tied to neutral?

I have a drawing of the wiring setup, but I can't post it since this is my first post. Maybe if you PM me I can send it to you.

Scott

HoustonRemodeler
Re: What to do with neutral wire?

Scott,

Yes you can change the location the power enters the lighting circuit. There are a few ways to wire 3-way circuits, depending on where the power enters the circuit. Google image search for 3 way wiring diagrams and find the one that matches your fixture layout.

scott180
Re: What to do with neutral wire?

The issue isn't about how to wire the three way switch. I have that. The issue is what to do with the neutral that doesn't have a place to connect.

It brings the switched power from the lower light switch to a junction box. I have a neutral in the junction box. But the switch doesn't have a neutral in it. Just a three wire run to the other switch, with all three wires carrying power.

Do I leave both ends of the neutral not connected?
Connect one end in the junction box and leave the other end float?
Connect one end in the junction box (ground or neutral) and connect the other end to ground in the switch box?

JLMCDANIEL
Re: What to do with neutral wire?

i think you have a problem, with this new run you will not have neutral to the lights. The easiest way would be to install the new run to the lights where the old one is now located.

If you want your drawing posted e-mail it to me [email protected] put TOH PICS in the subject line and include your TOH user name or a link to this thread. I'll psot it for you.

Jack

JLMCDANIEL
Re: What to do with neutral wire?

In this case you can cap the far left neutral at both ends.

Jack

scott180
Re: What to do with neutral wire?

That seemed like the best way to do it, I just didn't know if there was some funny code thing where it has to be treated a different way. Thanks for checking on this.

Re: What to do with neutral wire?
scott180 wrote:

That seemed like the best way to do it, I just didn't know if there was some funny code thing where it has to be treated a different way. Thanks for checking on this.

Actually just cap off the neutral in the downstairs switch box. By 2011 Code it's required.

Also, cap off the hot from old power source.

Now both the the upstairs and downstairs lights will be controled by the 3W switches.

Dave357
Re: What to do with neutral wire?

Actually, you're just transferring your problem to the neutral, not eliminating the problem.

If you run a new hot wire to feed the lights, you also need to run a new neutral wire. If you continue to use the existing neutral, then you will only have eliminated the overload from the hot wire, while the overload will still exist on the neutral wire.

Run a new 2-conductor cable to one of the basement lights. The black wire will be your new hot (unused at the light). The white wire will be your new neutral.

Also run a new 2-conductor cable from the light to the lower switch. Connect the black wires together in the light. Use the black wire for your new hot at the lower switch. Connect the white wires together, along with the existing white wire(s) in the light. The white won't be used at the switch, but is required by code. Just cap it off & stuff it into the back of the box.

When you disconnect the old hot at the top of the stairs, also disconnect the old neutral.

Hope this helps.

Dave

Re: What to do with neutral wire?

Actually, the drawing is fine as-is and, very well done.

Personally, I would leave the neutral from the junction box to the downstairs switch connected in the JB and cap it off in the downstairs switch, ready for future use.

And yes, there must be a neutral (as well as the hot)in the upstairs switch box from the old feed. Both need to be capped off so you don't have parallel neutrals or hots.

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