Electrical Basics ~ Residential Wiring Diagrams

Wiring Diagrams ~ Common Switched Outlets...

Switched outlets are generally, used to switch on and off table lamps. They are common in living rooms, where there may be no overhead lighting. Or in a bedroom, located near a night stand for example.

Typically, the outlets will be half switched. Meaning that only the top portion of the outlet will be switched. While the lower, is always hot. This is achieved by breaking the brass tab, on the "hot side" of the outlet, that ties the top and bottom together.

In the diagram above, you will notice both a "Source A" and a "Source B". Since power is often fed through the system, it can work being fed from either end. Simply match the source in the diagram to your own situation.

The wiring is pretty straight forward. You have power in, then a switch leg and power out to the next device on the circuit. The switch and outlets are tied together using a 3 wire NMB cable. Standard practice is to use the red wire as the "switched conductor" and the black wire, as the constant hot. Connect these to the brass side of the outlet. Red to the top half and black to the bottom. The neutral/white wires will connect to the "silver" screws of the receptacles.

I always switch the top but others may switch the bottom. Either is fine...just make sure that they are all the same.

Another common place to find a switched outlet is at a garbage disposal. Often, the power will be fed to the receptacle under the sink. Then, using a 2-wire "switch loop", power is sent up to the switch. The outlet may or may not be half switched.

In this example, power is fed into the outlet, that will be "half switched". The neutral/white wire from the source will connect directly to the outlet. While the black/hot wire, is pigtailed twice. One goes to the bottom half of the receptacle and the other ties to the switch leg out. It will connect to the white wire. Don't forget to re identify this conductor with some black tape. The black/hot wire of the switch leg will connect to the top half of the outlet.