3 way switches weirdness!

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condoowner

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Hello fellow HouseRepairTalk members!

I am not very knowledgeable in wiring, electricity and such, but I've replaced several 3 way switches and light fixtures to this day and never happened to be stuck with a weird wiring configuration. Basically, I have 2 light switches controlling a light fixture.. Basic 3 way config you will say (and maybe it is..) but I am confused with the wires. I only wanted to replace the switches and the light fixture, but I forgot to mark the wires and now I am lost..

Right now I have:

1 switch that has NOT been modified in any way (not replaced and not tempered with) this is switch 1 in the diagrams!!
1 switch that I replaced (and perhaps inadvertently wired wrong....)
1 light fixture that puzzles me....

So to be clear I've put together 3 diagrams of what I saw when I went to reinstall the switch and fixture..

These are the symptoms that something is NOT wired properly:

Switch 1 needs to be ON for the light to turn on, or else switch 2 is useless (but still has power to it!)
While switch 1 is OFF, switch 2 has power (its a dimmer and the green LED is lit up) indicating there is power going to it
If switch 2 (the dimmer) is dimmed to a minimum, the light fixture is lighting at 20%. I have an identical dimmer somewhere else, when the dimmer is at lowest setting, the light is off...

Please look at my diagrams.. Next step is to call an electrician if I cant figure it out on my own!

Thanks!!!!!

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It's a three way switch loop.
The white wire at the light is bringing unswitched power to the sw#2 and sending it through to the sw#1 on the white. The white at sw #1 is the common connection.
The black at sw#2 is the switched hot going back to the light fixture. The black at sw#2 should be on the common screw.
 
I think Ive fixed it, but Im not sure how... :)

I basically looked at the diagrams at the website you refered me to, and looked at the wirting diagram of the dimmer switch instruction leaflet, and noticed the black traveller wire from switch 1 is going to the screw on the left side of the dimmer swirtch, and the red traveller wire going to the lower (silver) right screw on the dimmer switch.

Then the common stayed on the black screw on the dimmer switch.

I basically had reversed the travellers... Now its working perfectly!! The only thing is, when the dimmer switch is ON but at lowest setting (the dimmer at the lowest intensity), the lights are very faintly lighting ON..

So 2 questions:

If everything "seems" to be working properly, no heat, no noise, no flickering, can I assume all is OK and let it like that or will I burn the house down???

Whats going on with the dimmer at 0% and lights still on?

Thanks!!

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AC power cycles on and off 60 times a second. A dimmer switch just keeps it off a little before coming back on, it should not be used as an off switch.
 
Ok understood!

Thanks guys!! Until I notice anything wrong, case closed!! :)
 
Oops, case unclosed! ;)

I went to install permanently the dimmer switch and noob's mistake, I realized the electric box is TOO small!!! ..... SO I went to buy a Leviton switch that is smaller than the Cooper dimmer I first bought, but still, it comes with 3 wire nuts and I can foresee this being a problem to fit everything in a 2" box... I cannot enlarge the box as it is sitting against a firewall (between 2 condos) and that's probably why the builder installed a 2in box at first.

So I am left with 2 options: install the dimmer away from the light fixture (not my favorite but it will do) or find a dimmer that will fit in a 2in electric box WITH everything else (wire nuts, wires, etc......)

Are you guys aware of such dimmer? Why are they so large???? Maybe you guys can recommend a dimmer that has remote control? SO I could put it on the other switch and use a remote to dim the light...
 
Hey TGMcCallie,

I have visited a Lutron reseller, and was surprised to see that the switch you suggested will barely fit in the 2" electric box I have to deal with... I have contacted Lutron and they are not recommending installing a dimmer in such small box due to heating problems and potential failure of the switch. This apparently could result in a fire which I am not interested to even consider.. They however recommended a Maestro dimmer with a remote controller to install in location #1 (the large box). Remember, this is a 3way application!! I have sent an email to them to ask to specify which model exactly I should buy but they have not been of real help.

I understand there is a dimmer that Lutron manufacture that has IR capability and comes with a remote controller. I happen to own a Logitech Harmony One remote controller. I was wondering if it would be possible to control the dimmer switch with my Logitech Harmony ??

So I am left with only 2 options:

Maestro IR dimmer in location #1 (the far one) with a remote controller and a normal switch in the 2" box
No dimmer at all... :(

Anybody can comment or recommend the exact model I should get? I found Lutron's website to be a pain as there are too many products, and there is no product finder wizard....

Thanks!
 
solved! I have installed a lutron wireless dimmer in location #1 (the larger outlet box) and made up an adapter plate for the pico remote at location #2. An electrician told me how to get rid of the 3 way feature and now it is only a one way light with one switch, the other one all wires being capped... (with the power passthrough of course..).

For the adapter plate for the Pico remote, I have used a pair of small round magnets glued to the plastic plate with cyanoacrylate (crazy glue). That being said, I am wondering if it is safe to use that, due to the proximity of the magnets to the wires in the box, and because the remote is literally next to the magnets.

Anybody think its unsafe/will create problems? On the wire side, I am thinking about electrical interference... on the remote side, I am thinking about radio interference and potentially turning on the light while no one is home???? Possible? The remote uses RF.

Look at the pictures, at least this looks sharp!

Thanks!

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Reactions: Gib
Nice Solution. The 2" deep box was not a good idea when it was first installed.

The small magnets won't bother the electrical system. They could affect your remote switch electronics but it's worth trying anyway. If they do affect the remote switch, there's no harm to anything else.
Gib
 
The 3way switch weirdness continues where I am trying to determine what to do with a 3 way switch setup with a ceiling fan..

When I moved in here, there was a standard 2 wire ceiling light fixture in the hallway. If I recall (it was in the beginning and I haven't used the light often), there was 2 switches controlling the light, one switch from one end of the hallway, the other at the other end. Standard 3 way setup.

Now I have replaced the ceiling light by a Monte Carlo ceiling fan with integrated light. The fan came with a remote controller. Being "stuck" with the wall switches, I decided to leave them as is, and I thought that they would allow to turn the ceiling fan ON or OFF, without bothering with the remote controller... My problem is that they seem not to do anything. In other words, they are totally useless, to the point thinking they control something else all together...

II turn the fan ON (true for both motor and light) with the remote, flipping the switches ON/OFF will not do anything at all... I even disconnected the switches and the fan was still operational.

Back when it was a normal light fixture, the red wire was capped with a wire nut. The wireless module that came with the fan did not allow me to use the red wire as it had only 2 wires (black & white) so I kept the red wire capped with a wire nut.

Plain simple a picture's worth a thousand words so I have prepared a diagram to explain what I had and what I now have...

Any clues as to why the switches seems not to be doing anything and is it unsafe/dangerous????? What should I do next? Cap the switches and their wires off???

Thanks to all!!!

sketch.jpg
 
In a 3way switch the red wire goes to one switch from the other. The unused red at the light box was probably put the for a fan to be installed at a later date. I suspect you have an extra red in one of the switch boxes for the fan and you have wired up the wrong one. Just a guess;)
 
Hey Neal, I'm very confident that I did not wire the wrong red wire.. the switches were replaced on the fly, that is I took the old one out and immediately put the new one with the wires exactly at the same terminals...

That's weird.
 
If you google 3way switches you will find some diff ways these are wired, you are going to have to sort what you have, what wires go where. Then you could have a bad switch or wire.
 
ok some research was required but I have progressed quite a bit in understanding the system. Folks used in electrical wiring might be able to explain to me how it really works. I quick survey with a multimeter and finding the source from the panel and a nice sketch helped quite a bit.

Basically, this is EXACTLY what I have. Now I understand why the fan always is powered on, even if the switches are off... the power routes from the main panel to the switch 1 (SW 1) then to the wire nut in the middle, then to the fan... Not sure of the purpose of such config.

Also, through deduction and logic, the switches must be wired as shown on the sketch.

It would almost look like a normal 3 way setup only if it had not the strange middle cable ... what that cable is doing???

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I think I just understood... This is a 3 way setup ONLY for the light. THe motor (fan) is always powered on hence the hot wire going to the SW 1 then to the fan, but the light would require a wire nut at the ceiling fan location to tie to the neutral. Doing so, the switches would act as a 3 way switch setup for the light only. make sense?
 
The lumps in your spaghetti will make it hard to chew.;)
You have power coming into box "A" and you have a 3 wire running to box "B" with a 3 wire running to the fan/light. Either the red or the black should be hooked to power and to the fan with out a switch as the older fans had power and were controled with pull chains for on/off, speed,and direction. Once you have that figured out you are back to wiring the switches properly for the light. Another box and switch could be added to control the fan.
 
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