When doing electrical wiring or any wiring for that matter, making the connection is one of the most important parts. If your wiring connection is not done correctly there is a good chance that the circuit will not work, or not work for long. With electrical wiring there is even a chance it may cause a fire.
If you are going to do it yourself, make sure you do it right.
Making a electrical splice.
The first type of connection we will cover is making a splice, defined as connecting one or more wires together.
How to make a splice.
1) Use an electrical meter to make sure power to the circuit is off.
2) Determine which wires need to be spliced together.
3) Next you will need to route the wires into an approved
electrical box of the proper size using an approved connector.
4) If the box is metal box, you will need to connect the ground wire to the box with an approved green ground screw. If it is a plastic box, you don’t have to worry about it.
5) Now you are ready to splice the conductors together. Use a pair of linesmen pliers to twist the conductors together.
6) Next twist the approate size
wire nut
onto the twisted conductors until it is fully tight.
7) Pull on each conductor to insure that each one is secured in the splice.
8) Finally install an approved blank electrical cover on the box.
Making connections to a device.
When making a connection to a device such as a receptacle or a switch, make sure to use the provided screw terminal. Never use the hole in the back that allows you to stab the wire directly into the back of the device. I have seen many problems with the stab back type of connection.
Proper way to connect to a device.
1) Strip back about ¾” of the insulation.
2) Use your strippers or pliers to bend the conductor to fit around the screw terminal.
3) Wrap it around the screw terminal.
4) Tighten the screw terminal.
5) Pull on conductor to insure you have a tight connection.
Tip: After all connections are made it can be useful to wrap electrical tape around the screw terminals. This can help make sure that the bare ground wire doses not touch the screw terminals. It can also be useful if the device is ever pulled out of the box while energized. This is an optional step and is not required.
Connecting to a device using stranded wire.
When connecting to a screw terminal using stranded wire you will need to use a
spade terminal
.
1) Strip back about ½” of insulation.
2) Slide to spade terminal onto the wire.
3) Crimp the spade terminal with the appropriate size crimping tool.
4) Place under screw terminal and tighten.
5) Pull on conductor to insure you have a tight connection.
Related Resources:
National Electrical Code Handbook
National Electrical Codebook
Stallcup's Illustrated Code Changes
The Complete Guide to Home Wiring (Black and Decker Complete Guides Series)
Wiring Simplified
Guide to Using the National Electrical Code
Residential Remodeling and Repair Professional Reference
It is important to note that electrical codes change, and that in some areas local electrical codes are not the same as the National Electrical code. The local authority having jurisdiction in your area may have different codes than the national code. It is important to find out if your local codes differ from the national code, your local authority having jurisdiction is the final judge and jury.
Caution: To prevent severe shock or electrocution always turn the power OFF at the service panel before working with wiring.