Either loosen the screws or use the wire strippers to snip the ends off and remove the old switch. Then tie the 2 black wires along with the black line wire on the idevices dimmer switch together with a wire nut.
Trying To Figure Out 3 Way Switch Loop Double Gang Multiple
Installing a dimmer switch with 3 black wires. From the dimmer 3 wire cable runs to the other switch and 2 wire cable runs to the light fixture. This simple diagram below will give you a better understanding of what this circuit is accomplishing. The source hot wire is spliced to the common on the dimmer and the neutral is splice through to the light fixture. It doesnt matter if you reverse the two switch wires to a single pole dimmer. Finish the job by installing the cover plate and turning on the power to test the new dimmer. A good rule is to not exceed more than 80 of the rate maximum for the dimmer switch.
Screw the dimmer to the box with the screws provided. When buying a dimmer switch check the maximum load its rated for. Wires going to the dimmer will be black and usually can be placed. Connect the ground wire from your dimmer to a green or bare copper wire in the wall box. Fold the wires neatly into the box. Black wire power or hot wire white wire neutral bare copper ground when wiring a dimmer switch circuit all we want to do is to control the black wire hot wire to turn dimbrighten the load.
Connect the black dimmer wire to your tagged common wire and remove the electrical tape. When installing dimmers for 3 way switches. At the 3 way switch the white cable wire is marked black and connected to the common terminal. For example if it has a limit of 600 watts you wouldnt want to install the dimmer on a switch that controls 8 100 watt recessed lights. Connect the two remaining dimmer wires called traveler wires separately to each remaining wire in your wall box. Install the dimmer.
Remove 34 inch of casing from the end of the house wires and the dimmer switch wires if needed. Twist the ends together clockwise and cap them using a wire connector nut. Remove all wires from the 4 way switch and cap both red wires with wire nuts.