Connect the black wire to the other brass screw. The switch it is connected to is a dimmer switch with an onoff button as well as a dimmer slider.
3 Way Switch Wiring Diagram
Light switch black and white wire. If the wiring does not appear to be correct then the wiring should be traced out and identified and corrections made as needed. This is a typical wiring setup for a 3 way light switch with black white red and ground wires. The white neutral wire connects to the silver screw or you place it in the back wire hole on the same side of the device as the silver screw. The neutral wire from the source is spliced to the white cable wire and continues on to the light. Run white wemo to this common wire you add. It should be labeled as hot with a band of electrical tape so it is not confused with a neutral wire.
If there is a white wire connected to the switch this is likely the switch leg. For the ground on the wemo just cap it off with one of the wire nuts. The other black and white wires are the electrical circuit for the switch. White wires are often used for switching however the white wire should then be identified with black electrical tape or a permanent marker. One of the black and white wires goes to the light fixture. If you dont have a ground wire leave the green screw unconnected.
The hot wire in a 120 volt residential ac circuit usually is coated with black insulation while the return or neutral wire is white. Wiring a three way switch. One of these is the power feed and one is the switch leg but the switch terminals are interchangeable so there is no need to identify which is which. Run 2nd wemo black wire to black wire from old switch. Wemo black wire to the white wire from old switch. A single pole single throw switch such as a light switch.
Wiring two switches for two lights here two switches are wired in the same box to control two separate lights. Mark the white wire with a piece of electrical tape to indicate that the wire is now a hot wire. Then attach the white wire from switch one to a contact on the light fixture. You have to have a common and i did was run a single wire from a box that uses a common wire. This wire is sometimes red. Take the white wire from switch two and twist it with the black wire from switch one.
The black hot wire goes to the brass screw or into the hole in the back of the device on the same side as the brass screw. The wiring in the ceiling contains a black red and white wire as well as a ground. The other may be black red or white. Attach a wire nut. Attach the black wire from switch two to a contact on the light fixture. The fixture contains only black and white.
At the light the white wire connects to the neutral terminal and the black wire connects to the hot. If you have a ground wire connect the ground wire to the green screw. If the light can be turned on or off from switches at each.