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miswired 3 way Switch

Posted on 1/13/20 at 8:54 am
Posted by GeekedUp
Virginia
Member since Jun 2009
1965 posts
Posted on 1/13/20 at 8:54 am
Hoping someone can help give direction on a 3-way circuit I’m struggling with. It hasn’t worked correctly since we’ve lived here, so I believe it was wired incorrectly by the previous owner. I am changing one of them to a smart switch and would like to correct the issue while I’m at it. In short, one switch (“switch 1”) has to be in a specific position for the light to work. Switch 2 is the one I’m changing to a smart switch since that box has the natural wire bundle.

Here’s what we have from what I can tell so far:

Switch 1, Manual,
• Wires in box are White, Black, Red, and Ground
• The WHITE wire is hot at all times.
• I have wired this to the common/line terminal on the manual switch.
• Black & red are therefore the travelers. My understanding is that the order doesn’t matter.

• Switch must be in a certain position (“on”) in order for switch 2 to control the light
• If in the “off” the light obviously goes off, but switch 2 can not turn the light on

Switch 2, Smart Switch (TP Link, KASA 3 Way)
• 2 gang box. I have not removed other single-pole switch for inspection. It appears to have a RED wire on one of the terminals if that helps anything. It operates a separate light
• Wires on previous 3 way switch: Black single, 2 reds
• Other wires in box: Neutral wire bundle, black wire bundle
• I have wired the smart switch: black to the to the common (I believe this goes to the light), reds as travelers, white to neutral bundle.

So now the set up operates as it did before with switch 1 having to be in a specific position for switch to work. The smart switch receives power at all times as LED on front is lit up regardless of switch 1’s position.

I have not removed the light fixture or the other single pole switch. I’m wondering if something is jacked up with the red wires in the switch 2 box. There were two red wires connected the original switch 2 but only one to switch 1. Seems like the travelers should be the same. Also odd that there is a red on the single pole switch.

That’s a lot of words. Any ideas on what’s going on and how to wire so that it operates appropriately? I thought about moving the smart switch to Switch 1, but not sure that makes sense with the neutral bundle in the other box.

Thanks in advance
Posted by notsince98
KC, MO
Member since Oct 2012
17954 posts
Posted on 1/13/20 at 9:55 am to
sounds like switch 1 is a standard switch and not a 3-way.

EDIT: Sorry, i thought I had typed this but I apparently didn't.

WHITE SHOULD NOT BE HOT!! That should be a neutral or a grounded neutral conductor. It should read 0V when measuring to ground. It isn't wired properly.
This post was edited on 1/13/20 at 9:58 am
Posted by GeekedUp
Virginia
Member since Jun 2009
1965 posts
Posted on 1/13/20 at 10:46 am to
Yep. Thanks for the reply.

White should read zero regardless of the position of switch two, correct? I believe I read voltage on it when switch two was in both positions, but I did not Disconnect switch two completely and read it.
Posted by notsince98
KC, MO
Member since Oct 2012
17954 posts
Posted on 1/13/20 at 10:52 am to
quote:

White should read zero regardless of the position of switch two, correct?


I'd really have to see the wires in person and figure out where the load is in relation to the wire.

Typically, yes, the white should always read 0V but if they aren't using the white as a neutral it is hard to say what it should read.

did you check the panel to see if the white lands on the applicable breaker there? if there are multiple loads on the circuit, they could have miswired it from another device.
Posted by East Coast Band
Member since Nov 2010
62725 posts
Posted on 1/13/20 at 10:58 am to
You can follow 3 way switch wiring diagrams online fairly easily, if you're inclined to that, which I assume you are.
Just note some are a little different depending if the lights are before or after the switches or in-between them (as in the power flow)
As far as the hot being white, it must be a white wire coming out of your breaker box that way, or it's been mixed up in some junction box, most likely in the lighting box.
Just gonna guess here that the power goes to the light first, then is run down to your switch 1 then to switch 2. Somewhere in the connectors by the light a black wire is crossed with a white wire
Posted by guedeaux
Tardis
Member since Jan 2008
13609 posts
Posted on 1/13/20 at 11:03 am to
Do you have pics of the switches as they were wired?

Does the KASA allow a dumb traveler? I am not familiar with those switches, but a lot of them require a smart companion or alternative wiring for 3 way to function properly.

Posted by baldona
Florida
Member since Feb 2016
20391 posts
Posted on 1/13/20 at 11:06 am to
quote:

As far as the hot being white, it must be a white wire coming out of your breaker box that way, or it's been mixed up in some junction box, most likely in the lighting box.
Just gonna guess here that the power goes to the light first, then is run down to your switch 1 then to switch 2. Somewhere in the connectors by the light a black wire is crossed with a white wire


This. I have found with 3 ways the best thing to do is to pull the switches out from the wall dangling by the wires. Do NOT remove any wires. Take a picture of it. Then measure the voltage of the wires with the switches in each position. Mark the wires.

Then go from there. I've changed out plenty of switches that were wire incorrectly or had just a strand of a different color for who knows what purpose.
Posted by CAD703X
Liberty Island
Member since Jul 2008
77945 posts
Posted on 1/13/20 at 11:12 am to
i know this may not help, but when i wired my new lutron dimmer 3-way it required that i rewire the other 3 way switch even though it worked fine before.

the lutron came with an extra wire that i had to connect to the old switch and i had to completely rewire it before it would work correctly.

since smart switches require a common to operate correctly you will likely need a slave switch designed to work with the first switch or you'll always end up cutting the current when you flip the older one.

lutron is the only smart switch i know of that doesn't require a common.

did the switch come with any documentation on wiring the other 3way switch?
Posted by Clames
Member since Oct 2010
16538 posts
Posted on 1/13/20 at 11:40 am to
quote:

WHITE SHOULD NOT BE HOT!! That should be a neutral or a grounded neutral conductor. It should read 0V when measuring to ground. It isn't wired properly.


As someone who just replaced a whole house's worth of 3-way switches, let me clear this up.

Under newer practices, this is correct but in homes built in the 1990's and earlier it is entirely likely to have a white conductor as the common line. It's a conductor like the red and black, it's perfectly capable of being hot and a good electrician will mark such a wire.

Now, in terms of trying to figure out which wires are hot, you don't measure for voltage, you need a good NCV device. This is AC power, there's no polarity to tell you what wire is carrying the potential, only a non-contact voltage device can tell you that. Take pictures of the current wiring arrangment, the remove ALL of the wires from both switches and separate them enough so the NCV has room to help you isolate the hot wire. If you go in assuming the white wires are neutral in this arrangement, you'll be in for some frustration and maybe some sparks.
Posted by East Coast Band
Member since Nov 2010
62725 posts
Posted on 1/13/20 at 12:25 pm to
quote:

the remove ALL of the wires from both switches and separate them enough so the NCV has room to help you isolate the hot wire

But do note that it is possible that the hot from the breaker goes to the light first. Probably shouldn't be that way, but possible
Posted by notsince98
KC, MO
Member since Oct 2012
17954 posts
Posted on 1/13/20 at 2:36 pm to
quote:

This is AC power, there's no polarity to tell you what wire is carrying the potential,


There is no polarity but you can easily measure potential. The Neutral is bonded to ground. It will most definitely measure 0V when the circuit is open.

You should be able to measure 120V rms AC to ground or the neutral from either of the two hot wires.
Posted by GeekedUp
Virginia
Member since Jun 2009
1965 posts
Posted on 1/13/20 at 3:08 pm to
Thanks all. I'm going to break back into it after work and see what's up. One of the odd things to me is that there are 2 red travelers on switch 2, but only one red traveler on switch one. Just odd.

I'm guessing that hot white line is coming over from the 2 gang box somehow.
Posted by papasmurf1269
Hells Pass
Member since Apr 2005
20883 posts
Posted on 1/13/20 at 4:34 pm to
Sounds like whoever wired it is using black and white travelers and a red switch leg. ETA If you look in The other box you will probably find a black and a white made up together
This post was edited on 1/13/20 at 4:37 pm
Posted by Clames
Member since Oct 2010
16538 posts
Posted on 1/13/20 at 7:32 pm to
quote:

The Neutral is bonded to ground.


That entirely depends of when the house was built and how the load is connected between the switches. The one I recently worked on was built in the mid-90's and no, you won't see a potential if the white wire you are poking at is a traveler because it is not bonded to anything but the other switch. It's entirely possible, and to code at the time, that you can have white conductors at the switches and none of them are neutral bonded because that happened at the light receptical.
Posted by GeekedUp
Virginia
Member since Jun 2009
1965 posts
Posted on 1/13/20 at 8:59 pm to
quote:

Sounds like whoever wired it is using black and white travelers and a red switch leg. ETA If you look in The other box you will probably find a black and a white made up together


This might be it. Here’s what I found: in the 2 gang box, the white wire was bundled with the black. One red appears to go to the light as it comes on when energized.

I was expecting the lead to the light to come from switch 1 (the single gang), so I’m turned around now.

So what now? Do I re-wire the white back to the black bundle? Without it, there’s no power to switch 1. If I reconnect it, does the white connect to the common on switch 1?

And what about switch two?

Sorry for all the questions, but I’m not familiar with this setup. THANKS!!!












This post was edited on 1/13/20 at 9:01 pm
Posted by Clames
Member since Oct 2010
16538 posts
Posted on 1/13/20 at 9:56 pm to
You are going to be pulling your hair out if don't have a NCV. Do you have a grasp on how 3-way switches work? Common switching between the two other terminals? On one of those switches, one of the common terminals was the hot coming in for the whole mess. That old switch with the white wire on the black common terminal in the first picture? That ain't it, that white wire is in the traveler run and I would think it's also the one connected to the black wire at the other switch, providing the common hot connection needed. It's very hard just by looking at your pics to figure out exactly what is going on, it seems you moved the black wire from the adjoining switch over and now it's mixed in with wires we don't need to be concerned with.


You seriously need one of these for this kind of work as a DIYer.

Posted by GeekedUp
Virginia
Member since Jun 2009
1965 posts
Posted on 1/14/20 at 9:43 am to
Believe I have that exact one! I prefer the multimeter. Im familiar with standard 3 way wiring. This isn't it and is my guess as to why is wasn't working properly before.

I went up at halftime last night and pulled the black bundle out of the light box. The source/line wire is actually in the light box.

It then sends power to the 2 gang switch box. There it was originally bundled with a white wire which sent power to the single switch. Again though, the light didn't operate properly as a 3 way originally, so I'm trying to figure how it SHOULD be done.

The switch leg to the light is the red wire also in the 2 gang box. I thought the source wire and switch leg would be on different switches and connected by travelers. Something similar to this maybe?



Is that the purpose of the white wire bundled with the black - to send power to switch 1? This would connect to the common on switch 1 w/ the red & black being travelers?

It would seem like that would leave me short a terminal on switch 2:
-Common (from light box)
-Traveler 1
-Traveler 2
- Switch leg to light

Does that help? Thoughts?

This post was edited on 1/14/20 at 10:06 am
Posted by GeekedUp
Virginia
Member since Jun 2009
1965 posts
Posted on 1/15/20 at 7:39 am to
Following up here. I got it squared away last night and wanted to share in case it’s useful to someone else down the road.

My house was wired similar to the diagram above w/ the common wire coming from the light. The confusing parts:
• The circuit was not working properly at the beginning, so you couldn’t trust what was there. Might have been a good thing. See below.
• Source wire was bundled in box 2 and routed to box 1 rather than going directly there from the light
• Hot wire coming from box 2 (above) was white and not marked
• Switch leg to light was red instead of black.

I think the previous homeowner trusted the conventional color usage and switched the black traveler with the red switch leg during a remodel. In any case, it works perfectly now and the smart switch is always appreciated. Love the timer feature for when the kids leave the light on.

For anyone else troubleshooting a 3 way circuit, here are a few tips and rules:
• Take pics before disconnecting the original switches
• Identify the hot
• Don’t trust the wire colors
• Know the hot and switch leg (wire to light) have to be different switches
• Hot goes on the common terminal of one switch
• Switch leg goes on the common terminal of the other
• You must have two travelers, but the configuration (position 1 & 2) doesn’t matter

Thanks for the responses here. No one had the “answer” but talking through it was helpful and kept the thought process going.
Posted by Miketheseventh
Member since Dec 2017
5707 posts
Posted on 1/15/20 at 9:30 am to
One thing you need to verify is that the travelers on switch 1 is indeed the same two travelers in switch 2. With the wires being different colors this is critical for the switches to work correctly. First thing is make sure there is no power on the travelers and then you can verify this by connecting the two travelers together at one switch and at the other switch check between the two travelers and make sure that you have continuity between them. After you have confirmed that then focus that you have power at one switch all the time on the other screw on one of the switches. On the other switch you have to make sure that the wire that’s not a traveler is going to the light as it’s hot wire. Hopefully this gives you some trouble shooting guidance
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