3 way light switch question


  #1  
Old 01-13-21, 07:49 AM
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3 way light switch question

I have a hallway light controlled by a 3 way that I want to put a smart switch in. I have the TP-link Kasa kit which only requires one of the switches to be smart if it can be connected to the line wire (which would allow the kit to replace two sets of 3 way switches instead of one!).
When I pull the switches this is what I see. I'll be figuring out which is line and load once my baby wakes up but my my question is - can I assume in the box with the black and white wire capped together that those are neutrals?
Every other box in the home had a neutral bundle stuffed into the back so this one is confusing me with the black and white capped together.
Thanks!



 
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Old 01-13-21, 08:21 AM
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You do NOT have a neutral in those switch boxes. You have a switch loop. The white is power into the switch and the black is switched power back to the lights.
If your switch requires a neutral you can't use it unless you pull new cables.
 
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Old 01-13-21, 09:43 AM
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OK thanks for the reply.

Do you know an alternative 3way no neutral smart switch that does NOT require an additional bridge or hub?
 
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Old 01-13-21, 10:07 AM
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Check at the other 3-way switch location. Since the switch you showed is connected to the light fixture (the black/white connection) the other switch has to have the power connection. If the power originates there then the neutral should be there also.

If the power originates at the fixture the neutral may end there and may not be in either switch box.

In a 3-way switch circuit the common screw of one switch is connected to the power and the common screw of the other connects to the fixture.

The sketch in Post #18 of this thread illustrates 3-way/4-way circuits and power at fixture.

 
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Old 01-13-21, 12:46 PM
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I should clarify that the two pictures are of two DIFFERENT switch boxes in the 3 way circuit if that changes anything.
In one box is just 3 wires going directly to the switch.
In the other box are 3 wires going into the switch and two separate wires (black and white) capped together.
 
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Old 01-13-21, 01:17 PM
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It changes nothing. There is no neutral at either switch.
 
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Old 01-13-21, 05:26 PM
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joed is correct.

The second switch is called a dead end 3w switch since there is only a 3 wire cable there.

There are a few smart switches.....actually smart dimmers..... that don't need a neutral.
They're in the link below. I do use the Lutron Caseta but it requires a Lutron hub.

Some smart switches not needing a neutral.
 
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