Electrical Wiring in the Home/Dimmer Switch


I have a hall light that is controlled by 4 switches.  I want to add a dimmer switch and the guy at the hardware store said I can only add one dimmer and it has to be on the one switch that is a 3 way.  That switch has 2 black wires and one orange. I connected up the 3 way dimmer and it does not work with the other switches.  If the other 3 are off the dimmer wont turn them on.  

Any thoughts?


A few.

To be clear there are two switches of the 4 that are 3 ways and the other two are four ways.
The 3 ways have 3 terminals and the 4 ways have 4 terminals. You can put the dimmer in either of the 3 way switch locations.

You either got a bad dimmer or you connected it wrong which isn't hard to do. You MUST know which is the "common" wire on the 3 way switch and connect it to the orange wire on the dimmer which is the dimmer "common". The "common" terminal on a switch is designated by a dark colored screw. The "traveler" terminals are designated by a "brass" color. It does not matter which of the remaining two wires is connected to either brass terminal, you just have to get the "common" right. The same applies to your 3 way dimmer. The two black wires are the "travelers".

If your not sure at this point which wire was the "common" then just mark the one that is currently connected to the orange wire on the dimmer. Once you have it marked disconnect it and reconnect it to one of the other two wires from the switch box and take the free wire from the switch box and connect it to the orange. Check the dimmer and see if it works properly. If it does not then rotate the wires again in the same manner using the next wire from the switch box. Barring a defective dimmer it should work because you will have tried all 3 wires from the switch box as the "common".

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Electrical Wiring in the Home

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"The Frank Williams School of Electrical Construction". My dear old boss is 100 ! and still going God Bless him. I started working for "Tenafly Electric" right out of high school at 19. He was tough but I learned more working for him in 8 and half years than most guys. We did mostly industrial work while doing some commercial and residential so I was fortunate to be exposed to all 3 areas of electrical construction. The guys I worked with were all good guys and I stay in touch with some of them still. Most of us went into our own buisness's which says something about the caliber of the guys I worked with. We had some interesting clients : Wella Corp. of shampoo fame, Farah Fawcett etc, I didn't buy shampoo for 10 years. It was a great place to work. Pan Am the former airline just before they went under, another great place to work, nice clean environment. C&C Metals, the largest button manufacturer in the US at that time, a not so clean environment but a very interesting place to work, lots of machine's cranking out buttons of all kinds but you had to be on your toes, it was a potentially dangerous place to be . All kinds of action going on around you.

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