By law, spliced wires should always be kept inside junction boxes. Some homes have spliced and reattached wires and could be dangerous if left exposed. A junction box will help hold these wires and protect you and your home.
- Prepare tools. You should always have the right type of tools for the job at hand. You can consult a certified electrician if you are going to install the junction box by yourself. The tools that you are going to need are two types of screwdrivers; a Philips screwdriver and a flathead screwdriver for the different types of screws you will use. Have wire strippers ready, one for ROMEX wires and another to strip various types of wires. Decide on a type of junction box you need and have the appropriate cover for it. A pair of standard pliers and a long nose will come in handy when you need to twist wires and cut them to the right length. Two important tools you will need when working with electrical wiring are the electrical tester that tells you if you wired everything correctly and the AC tester that will warn you if there is still some traces of electrical current running through the wires you are going to work on. Have a hammer ready too; it will come in handy when you need to fix a component to a structure.
- Turn electricity off. Before doing any work on the junction box, first turn off the electricity running through the electrical wires. Go to your circuit breaker and turn off the switch that corresponds to the wires you will be working on. In some houses, you may have to switch off the main fuse box or remove a fuse. Check the wires that you will be working on and determine if there is no electrical charge running through them with an AC tester.
- Add the junction box. Depending on the type of junction box you acquired you may have to screw in, nail in or use a stud to secure the junction box to the wall. First locate the spliced wires and separate them; cut them if necessary. Once the wires are separated or cut, expose part of the wire with the wire strippers and pull them back to accommodate the junction box. Fix the junction box to the wall or joist with the screws. Put in the cable connectors and slide in the wires. Hold it in place using a pair of pliers to tighten the locknut.
- Twist the wires together. When all the wires are inside the junction box, twist the like colored wires together from their exposed ends to an inch of the insulator. Twist the bare copper wire and attach a wire cap on the wire ends to protect them from touching the box surface or other wires. You can use a different colored wire nut on the bare copper wire to signify that it is the ground wire. Then cover the junction box with the cover plate using the screws provided and then turn on the electricity. Check the outlet or device that the spliced wires are connected to with the electrical tester.
By installing junction boxes where there are spliced wires around your home you will avoid electrical accidents from happening.