You will have two 3-way switches on this circuit. You can replace one of them with a 3-way dimmer.

Hello,

Please see my Original Post at the top. The 4-Way switches are located as follows ... 1 on the 1st floor landing and 2 switches on the 2nd floor outside each bedroom.

I also meant to say a 3-Way Dimmer ... NOT a 4-Way Dimmer.

A 3-Way Switch controls a ceiling light from 2 locations
A 4-Way Switch controls a ceiling light from 3 locations
Am I correct in my thinking so far ???

I purchased a Lutron 3-Way Dimmer to Replace one of the 4-Way switches, located outside one of the bedrooms.

When I removed the 4-Way switch it had 4 Wires (2-Red, 2-Blk, and a bare ground). The new 3-Way dimmer only has 3 wires (2-Red, 1-Blk and a ground).

Did I purchased the WRONG DIMMER ???
If not can some one give some instruction on Correct Wiring.

Thank You All,

Lou B

In a setup with more than 2 switches controlling one lamp, the switches at the ends of the wiring chain are 3-wire and the ones in the middle of the wiring are 4-wire.

Like Bill said, if you have three switches, two of them are 3-way, one is 4-way.... you can have any number of 4-ways, but you will always have two 3-ways..

You've got the right dimmer, just pick one of the other switches to replace.A four-way switch just swaps the travelers between the two three-way switches. There is no neutral, incoming power from circuit box or outgoing to the light.

You need a Lutron Maestro dimmer setup. You replace a 3 way with a master and a 4 way with a slave unit.

Here is a link that might be useful: Lutron Maestro

what hendricus said -- you can't replace the 1 4-way switch with a dimmer, but you can replace either of the 2 3-way switches with a dimmer. Hopefully one of those is in the location you want to place the dimmer. If not, you can look into the Lutron system.