Capping Electrical Wires in a Junction Box

When it comes to electrical stuff, one should always be careful to avoid any unwanted and unforeseen accident. In a house where there are kids, it is extremely important to make sure nothing is hanging out. It is important to cap off electrical wires to remove a device safely from a circuit. If there is an uncapped energized wire, there will be a risk for a person making contact with it to get electric shock. It could also become fire hazard as the hot wire and a grounded surface contact will ignite the material, which is combustible around it. It will take a short time to cap off the wires and save your life and someone else as well. Here are the steps on how to cap off the wires.

You will need:

  1. Wire Strippers
  2. Blank Box Covers
  3. Wire Nuts
  4. Black Plastic Electrical Tape
  5. Wire Cutters/Diagonal Pliers

Junction Box


  1. First, turn off the circuit breaker or remove the Edison base fuse from the circuit that needs to be capped off. As a beginner, you should not cap off wires while they are hot as only professional electricians are able to do it.
  2. Then, cut the ends of the wires until they are flushed with their insulation. This will help you to work with a straight section of the conductor perfectly. Use the wire strippers to remove an inch of the insulation from the end of the wire that needs to be capped off.
  3. Screw tightly a wire nut over the stripped conductor. Tug on the wire nut with the other to make sure it holds while holding the wire tightly in one hand. Tape over the wire and the wire nut for it to be more secure so that it won’t come loose.
  4. Continue these steps until you have capped off all the wires. Make sure to install a blank cover on the box if you are capping off wires in a lighting outlet box, device box or a junction box. This covering step is needed as they are required by the National Electrical Code.
  5. Even though these steps are specifically for capping off electrical hot wires, the code will need you to cap off the grounded or neutral conductor. The neutral conductor can become a hot conductor if the break is between another neutral and load bar in the panel. The bare copper grounding wire is not a big concern, but you should cap off every neutral wire existed.

Image Credit:

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Additional Reading:

Live Wire: Women and Brotherhood in the Electrical Industry

Electrical Materials