A junction box is a box used to safely contain wiring connections or terminating a wire intended for future use.
All wire splices must be enclosed in a junction box.
Wires entering a plastic junction box enter through a slot do not need a clamp.
Wires entering a steel junction box enter through a hole or “knockout”. Before these wires can be routed through the hole, a wire clamp must be inserted and secured in the hole. The wiring is then fed through the clamp and secured. When securing the wire, make sure that none of the wires inside the outer covering/ insulation (black/white/copper) are visible.
Steel boxes must be grounded.
All boxes should be securely attached to a rigid part of the structure. All wiring connections should be in compliance with the national electric code. Wire nuts must be used. That is, electrical tape on twisted connectors is not acceptable.
Ground wires must be mechanically fastened together. A wire nut is not acceptable.
NOTE: All junction boxes must have a cover plate that is properly attached!