Installing an electrical junction box gives you freedom and flexibility when installing electrical cables.
It’s often used when an electrical circuit branches off in two or more directions.
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What Is a Junction Box?
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A junction boxis a standard electrical box that contains two or more spliced electrical cables.
The box must have a removable, accessible cover.
Junction boxes can be placed alongelectrical conduit, too.
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Choose the Right Junction Box
Install an electrical junction box that is appropriate for the installation.
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Attach Clamps to the Box
Install a cable clamp for each cable, as needed.
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Standard plastic electrical boxes do not have knockouts and contain internal cable clamps.
Tighten the nut with pliers.
Secure the Cables
Feed the cables through the clamps and into the box.
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Plastic boxes usually have spring-tabs for clamps and do not require tightening.
The ends of the wires should be clean, straight, and undamaged.
Trim any damaged wires and/or strip insulation as needed using wire strippers.
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Join the Wires
Join the wires together with approved wire connectors, following the manufacturer’s instructions.
Join the bare copper (or green insulated) ground wires together first.
Special green wire nut connectors are generally used to join the grounding wires together.
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If there are red (hot) wires, join them together, as well.
Confirm that all wires are secure by gently tugging on each wire.
Fit the Wires in the Box
Carefully fold the wires into the box.
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implement the box cover, securing it with two screws.
Code requires that the cover must be a solid “blank” without holes.
Restore power to the circuit by switching on the circuit breaker.
There also might be some more wire colors for other functions.
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