Question about Cooper Wiring Devices Three Way Grounded Switch, 15 Amp

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I am replacing a 3 way light switch with a dimmer switch. The existing switch has the green ground, two black on one side and a red on the other. The new dimmer has the green ground, two red and one black. I'm guessing that the red in the wall goes to the single black on the dimmer and the two black in the wall go to the two red on the switch. However, I don't want to guess.

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There is no universal convention on the color coding of wires for three-way switches, other than green always being ground. Fortunately if you wire it wrong you won't hurt anything, it just won't work right. Two wires are "travelers", they run between one three-way switch and the other. The "travelers" were attached to opposite sides of one end of your old switch. From your description, one is red and one is black. (These two wires are interchangeable, except that in one position both toggles up or both down would ON. In the other position one toggle up and the other down would be ON.) The "third wire" was attached to the other end of the old switch and is black. If you can't tell by just looking at it which lead of the new switch is alone at one end of the new switch (and is therefore mate for the "third wire"), you can just try the combinations. Assuming you still know which black wire is your "third wire" there will only be 3 combos.

Posted on Jul 28, 2010


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How do I connect an old 3-way toggle switch to my new 3-way dimmer?

Cookrobert- you have to determine wich wire is the common wire in the box (house). Look in the box and see wich two wires ore in the same sleave. (These will be your travelers, (more than likely a black and a red) the wire that is in its own sleave (black)with a white tied to other whites is the common. Now the dimmer will tell you wich wire is commom. Tie the tow commons together. The green wire is ground if your house does not have ground , cap it and forget the green, if your house does have a ground (bare copper wire) then connect the green to the bare wires is the house box. Now your to travelers on the house side will tie to the two travelers on the dimmer side. Once you have found the traveller's on the house side and dimmer travelers they can be flip flopped. It dosnt matter. Just as long as they are the traveller's it will work. It sounds complicated but I'm sure you got this. I'm a 30 year electrician. (master).. I'll be looking for your update my friend. Good luck

Jan 21, 2015 | Electrical Supplies

1 Answer

I am trying to install a Trimatron 6681 three - way in my dining room. the trimatron has two red wires, one black and one green. my switch has a red and copper wire on one side and two black wires on the...

It may be obvious, but the first thing to do is confirm that the power is off.

Do you have a DMM (digital multi-meter) or a voltage sensor?

It sounds as though you are replacing an existing 3-way switch with a new 3-way dimming switch, is that correct?

There should be another 3-way switch or dimmer somewhere else.

One of the the two switches has a hot wire coming into the switch from the breaker panel and two hot wires coming out that go to the other switch (as well as the neutral and ground, 4 conductors total, using special 3-way cable).

The second 3-way switch will have those two hot wires coming in and one hot going out to the load (the lamp or light) -- and the neutral and ground, 3 conductors total to the light.

In either case, the single hot wire either comes from the breaker panel or goes out to the lamp.

So, my _guess_ would be that the one red wire on the existing switch is the same as the one black wire on the new switch, and the 2 black wires are the same as the 2 red wires. Bare copper or green wires are ground wires, they are the same. Most house wiring uses bare copper, but some fixtures and switches use wires with green insulation.

I hope that's helpful. Remember, I'm just _guessing_ about the wires -- you should confirm with a meter (which will require turning the power on and checking with a meter -- be very careful.

Let me know if you have any questions.

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1 Answer

I have to replace trimatron push on/off Dimmer. the old that needs replacement has 2 "travelers" while the new one same manufacturere has back red and green. How do I connect to existing...

If the new one has black, red and green, then it must not be a 3-way. Green is universally the ground and the black and green would be the in and the out (either way) on a 2-way switch. You are one lead short! Good luck, Al K

Jun 01, 2011 | Rotary Leviton 836-6683I Trimatron Deluxe...

1 Answer

I would like to install a Lutron 3 way dimmer switch. The switch has a red, black, green, and white/red striped wires. The previous switch has 2 red and 2 black wires connected to it. The other 2 light...

The circuit you are working on is a 3-location circuit - where two of the devices were 3-way switches, and the remaining device (the one you are trying to replace with a dimmer) is a 4-way switch. Standard dimmers like the one you're using CAN NOT be used to replace a 4-way location. If you wanted to use it to replace either of the 3-way switches, that's no problem - but what you're doing right now will not work.

If you absolutely want to dim the lights from that specific electrical box, my suggestion is to upgrade to a "smart dimmer" where instead of a basic dimmer and two light switches, you have three devices that talk to one another and all dim the lights together.

In terms of your ground wire questions - ground wires certainly aren't necessary to make the whole thing work - rather they're there for safety. Sometimes installers will ground the device by connecting the ground wire to the backbox (assuming its metal) and then rely on the mounting screws on the dimmer or switch to perform the grounding. There are some code rules/exceptions for allowing the device to not be grounded (usually when its in a plastic, non-combustible backbox). If you want to make sure everything is completely up to code (which are usually goverened by local municipalities), you should consult a licensed electrician - but above all else, just use good judgement. Long story short, if the devices weren't grounded before, you can't make it any worse.

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1 Answer

We just bought a house and the living room has a light fixture and there is a dimmer switch that controls it. I removed the light fixture and installed a ceiling fan but the fan barely moves and the light...

You're correct. The dimmer switch was not made for that fan.

The Green is ground > so you're right there too. I assume other plugs nearby are working when dimmer is on. Check that to make sure.

By your description, I assume there is NOT another switch or dimmer that connects to same light. If so, you need a 3-way switch and the following instructions are void.

I suspect when you wired the new fan, that you saw the red and small black wires in the ceiling box. Did you connect the fan and light to those wires? If so, the following information will help you wire the switch.

Your incoming Hot line is probably the larger black wire that connects to Dimmer black >>> this wire will connect to either screw on the new switch

To test Hot wire for sure: Take out dimmer and mark wires for identification. Separate wires. Turn on power and test each wire to bare ground. Tape tester leads to wood sticks so hands are away from power. You'll be fine. Tester lights up on Hot wire.

Next: The smaller black and a red wires are a toss up.

Here's how I would proceed. Connect the black Hot to either screw on switch. Connect red wire to other screw. Put wire nut over small black. Turn on power. Flip switch. Check both lights and fan to see which works with red wire.

Next reverse the toss up wires. Put wire nut over red. Connect small black to switch. Check both lights and fan.

If red and small black control the light & fan, then connect them together on the same screw, and you're done.

If you want to control the fan and light separately, buy double switch, and then Hot connects to dark-colored screw on one side of switch, and red and small black connect to two different screws on opposite side of switch.

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1 Answer

I attempted to install a slide dimmer yesterday. when i pulled the existing switch off I had three black wires (two pushed in to the back of the switch and one wound around a screw) and one white wire...

The white and the black wires are both hot wires, and the green wire is for earth ground only. The green wire does not belong hooked up to the white wire.

The two black field wires should be attached to one side of the dimmer switch (one of the black wires from the dimmer switch)

The white field wire should be attached to the other side of the dimmer switch (the other black wire from the dimmer switch)

The green wire from the dimmer switch should be hooked up to earth ground only (any un-insulated copper wire that is inside the switch/outlet housing) and if you can not find it attach the green wire to the inside of the light switch outlet housing and be sure that it is attached to metal.

The other hall light switch that you are talking about must be connected inline with that light switch you trying to turn into a dimmer, and it should operate again nomally once you have connected that light switch properly, and if not check for any tripped circuit breakers.

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1 Answer

Replace 3 way dimmer but different color wires how to connect?

you will want to make the following connections
existing-black wall to black dimmer now connects to red dimmer
existing black wall to red dimmer now connects to black dimmer
existing red wall to black dimmer now connects to red dimmer
Green wire connects to bare copper wires in wall

Apr 26, 2010 | Leviton Toggle Touch Dimmer - TGI06-1LB -...

1 Answer

How to install a dimmer switch

This is a 3-way switch, made to control a light fixture that is also controlled by another switch in a different location. A typical example is a ceiling light fixture installed in an upstairs hallway, which could be controlled by switches at both top and bottom of the staircase.

The green wire in your switch is the ground connection, and joins to the green insulated or bare copper ground wire in the switch box. The red wire is the common connection. It connects either to the incoming AC hot wire from the electric panel, or to the hot terminal of the light fixture, depending on the switch location. The two black wires are traveller connections. They connect to the traveller terminals of the other 3-way switch.

If you purchased this switch as a replacement for a regular single-pole toggle switch or dimmer switch - one that controls a light from a single location only - then this isn't what you need and you can't use it. You'll know if you have a single-pole switch because it will have only three wires or screw connections. Return it and get a single-pole.

To install this as a replacement for a 3-way toggle switch or dimmer, connect the red wire to the wire going to the common terminal of the original switch. This will be a black- or brass-colored screw on a toggle switch, or the different-colored (not green, that's ground) wire on a dimmer. The black wires connect to the wires that go to the traveller screws (copper-colored) on a toggle switch, or the same-colored wires on a dimmer. It doesn't matter which traveller wire connects to which.

Note that if you're using a 3-way dimmer, only one of the switches can be a dimmer. The other switch has to be a plain old 3-way toggle.

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1 Answer

I have a trimatron dimmer which has a black, red, green and another red wire labeled 3 way. My box has two black , white, red and groud wire. this room has two seperate light switches that control the...

When you take the existing switch out of the wall, the existing switch will have one black screw and two gold screws. The wire that is connected to the black screw of the existing switch (probably on of the black wires from the box) connects to the black wire on the new dimmer. The other two wires (one black and one red from the box) that are connected to the two gold screws on the existing switch will connect to the two red wires on the new dimmer. Basically, wire from black screw goes to new black wire and wires from gold screws go to new red wires.

Sep 27, 2009 | Leviton Trimatron Rotary Dimmer 6602-i Lot...

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