Smart Switch Dumb Question


Old 12-12-19, 11:17 AM
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Smart Switch Dumb Question

So here it is. My first post in a forum in over 20 years. I bought a smart switch on Amazon for to sync with Alexa. I totally understand how to wire it in when you have a normal situation such as ( 2 neutrals tied together and black in/out of switch). In my case the power is supplied to the light first (whites tied together) so that being said. The existing switch has a black in and white out. So... Now I'm confused because I have 4 conductors on my smart switch. red black white and ground. How do I wire this in? I would hate to tear the ceiling apart to rewire.

Last edited by Tommy Dunleavy; 12-12-19 at 11:21 AM. Reason: Typos
Old 12-12-19, 11:49 AM
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What switch do you have? What do the instructions say the red, black, white and ground are for?

I assume ground is ground. Black and white might be the conductors for what you are controlling and red is always hot to power the switch. Another option is that your switch is a three way but your instructions should tell you either way.
Old 12-12-19, 11:52 AM
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Sounds like a Romex wired home. You can either replace the NM 2 conductor from ceiling to box with 3 conductor. Or, use a "no-neutral" required smart switch.
Old 12-12-19, 12:20 PM
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You can't install it without new cable to the switch. You do not have a neutral. The only way to get a neutral is a new cable with three wires.
Old 12-12-19, 12:24 PM
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Looks like I should just rewire it the correct way. If I'm gunna do something, might as well do it the correct way. Thanks for the feedback.
Old 12-12-19, 06:37 PM
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Before you go rewiring, they do make smart switches that don't require a neutral. That's most likely a much easier solution than running a new 3 conductor (plus ground) cable from the light to the switch.
Old 12-12-19, 06:39 PM
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The smart switches that don't require a neutral do require a certain lamp load.
Sometimes with one LED bulb... there isn't enough load to run the switch.

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