This article is written for a standard, grounded US outlet. If your home does not have grounded outlets just disregard the part about the ground wire. This outlet is called a duplex receptacle because it has two places to plug in appliances or lamps. A split duplex outlet is one where one plug is switched and the other is always on OR the two plugs are on different circuit breakers (under the sink for the disposal and dishwasher is the most common example of two circuits).
If you have a split duplex outlet continue reading this article.
You won't need many tools to perform this job and none of them are expensive in most cases a flat and Phillips screwdriver are all you need. Occasionally you will need a pair of pliers to reform the loop of wire (terminal loop). Also sometimes you will need a very small flat blade screwdriver if the device has been wired using the pressure terminals on the back of the device.
Turn off the power and then verify that the power is off to both halves of the duplex receptacle by plugging in a known working lamp or using a circuit tester. Then remove the device box cover. Under that you will find two more screws near the top and bottom of the box that actual hold the device in place. Remove those and gently pull the device towards the room. Until you have access to the terminals to with the wires are attached.
There are a couple of important things for you to check out at this time:
How many wires are attached to the device? Four, five or six?
In inspected work you should never find more than five wires attached to the device and four is the most common. If another outlet is fed from this box the "make-up" should be in the back of the box and not attached to the device. The white wire may be common or there may be two white wires. There will be no more than one ground or green wire. The two hot wires may be black or a black and a red. Any combination of these is correct as long as they are connected to the correct terminal to ensure correct polarity.
Should you find a different situation, you are going to need to correct or replicate it. This is one of those places where the here often repeated advice about good work habits and one wire at a time is going to save your bacon. Take one wire at a time loose from the old device and connect to the new device.
Breaking the connection between the plugs.
The little tab between the terminals must be removed on the hot side and may need to be removed on the neutral side. One white wire; DO NOT remove the tab on the neutral side.
Polarity is Important!
All modern devices go out of their way to make sure you follow the correct polarity. The screw terminals have been color coded for many years; but now the back of the devices are imprinted with the standard wire color information. The hot, black wire(s) is attached to the gold screw and the neutral, white wire(s) is attached to the silver screw. The green or bare is attached to the single, green screw.
The wires should have a neatly formed loop that looks a lot like a question mark except the loop should be a bit longer. That loop should be placed under the screw so that the open side faces in a clock-wise direction. The reason is so that the wire will be pulled to the screw as the screw is tightened.
Once you have all the wires are connected gently bend the wire so that the device can be properly seated in the box, replace the cover and turn on the breaker. Test for proper operation.
