Speaking of standards, NBR 5410 is ABNT's specific norm that mentions the necessary distance for junction boxes. In it, the specification is very clear: for internal pipes, the distance must be up to 15 meters, and, in external pipes, it must be up to 30 meters, in a straight. How far a box can sit behind the finished wall surface depends on whether that surface is combustible. 20 draws a sharp line between the two scenarios: Combustible surfaces (wood paneling, similar materials): The front edge of the box, plaster ring, or extension ring must extend to. Present in any type of electrical installation, the junction boxes are important for promoting the passage of the wires inside walls, as well as to connect wires to sockets and switches. Some people use the junction boxes to change the direction of the wires within the building or project.
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