The Collaborative International Dictionary
Junction box \Junc"tion box\ (Elec.) A box through which the main conductors of a system of electric distribution pass, and where connection is made with branch circuits.
Wikipedia
An electrical junction box is a container for electrical connections, usually intended to conceal them from sight and deter tampering. A small metal or plastic junction box may form part of an electrical conduit or thermoplastic-sheathed cable (TPS) wiring system in a building. If designed for surface mounting, it is used mostly in ceilings, under floors or concealed behind an access panel - particularly in domestic or commercial buildings. An appropriate type (such as that shown on the right) may be buried in the plaster of a wall (although full concealment is no longer allowed by modern codes and standards) or cast into concrete - with only the cover visible.
It sometimes includes built-in terminals for the joining of wires.
A similar, usually wall mounted, container used mainly to accommodate switches, sockets and the associated connecting wiring is called a pattress.
The term junction box may also be used for a larger item, such as a piece of street furniture. In the UK, such items are often called a cabinet. See Enclosure (electrical).
Junction boxes form an integral part of a circuit protection system where circuit integrity has to be provided, as for emergency lighting or emergency power lines, or the wiring between a nuclear reactor and a control room. In such an installation, the fireproofing around the incoming or outgoing cables must also be extended to cover the junction box to prevent short circuits inside the box during an accidental fire.
Usage examples of "junction box".
Our clever little pal left the doors open, disconnected the hand-operated levers so that they appeared to be in the shut position when they were actually open, and crossed over a few wires in a junction box so that the open position showed green while the closed showed red.
We'll try and install something at the junction box leading into the house, but we're not sure how well it will receive.
What he was looking for turned out to be a small junction box, similar to a telephone socket.
Destroy this one junction box and the radar's steering, power and electronics went with it.
His armored fist closed on the junction box the admiral had described in the planning stages.
Her feet slammed into a junction box and she stopped, swinging in the air.
He pressed the firing button, sending a signal to the junction box.
When I got home, Maria's husband Ari stopped me on the gloomy landing, where he was repairing a junction box.
She lowered her legs around the junction box, gripped the cable between her feet, let her body weight go down—.
Xris could only hope that Amadi's diagram was accurate, that the junction box was where he said it would be.
At the point where the two lengths met, the drones had installed a heavy-duty junction box into which they connected a data line which they had also just strung along the main cable run.
There had been no junction box in evidence previously, which meant that Spartacus was not simply repairing its earlier work.
I blindly traced the segmented cable with trembling fingers, found a junction box, a switch.