If you have a 2 gang or 3 gang switch you may have black and grey wires however these will have a brown sleeve on them as they are also switched live wires.

Switch with three wires.

On one of the 3 way switches a line or hot wire gets connected to the common copper or black screw terminal. Hi all i am replacing my single pole light switch and noticed when i removed the old switch that there are three black wires coming from the box. Another type is the four way switch which is used in conjunction with two three way switches to control lighting from more than two locations. I assumed it was a single pole switch as it is a simple switch to turn on the bedroom light and there are no other controlling switches but when i pulled the old switch out of the wall i found three black wires attached to it two go directly into the switch and a third is screwed on the side. The old switch was attached with two blacks inserted into the back of the switch. All the white wires are capped together and the same is for the ground wires.

The three way switch is a variation of the standard single pole switch which controls a light only from one location. Between each three way switch is a pair of travelers that are connected to the unlabeled brass terminals. On the other three way switch the load wire the load is the wire that feeds power to the light fixture gets connected to the common copper or black screw terminal. Pick the diagram that is most like the scenario you are in and see if you can wire your switch. Of the three black wires only one of them is hot. Three way switch wiring.

Wire nut the neutral white wires together. For example they can be arranged so that the feed cable runs to the first three way switch then to the light fixture box then to the second three way switch. Single pole switch with 3 black wires. Three way switches can be wired in a number of different ways depending on where they are located relative to the light fixture in the circuit cable runs. I am trying to install a dimmer switch in my bedroom. A three way wall switch is single pole double throw spdt with three connection wires and is typically wired with 12 3 or 14 3 cable between the two switches.

You will be replacing it with a new 3 way light switch. 3 way switch wiring diagram take a closer look at a 3 way switch wiring diagram. Two way switches are single pole single throw spst with two connection wires and are wired with 12 2 or 14 2 cable between the switch and fixture. This is the existing white neutral wire coming into the box and the new white neutral wire from the 3 wire romex you re going to use to connect the other 3 way switch you will install in a minute. This first step will eventually send power directly to the light fixture. The traveler wires are interchangeable between the two brass colored terminal screws.

The 3 wire system is less common than the 2 wire system it includes a neutral at the switch as well as the live and switched live wires.