Junction box
A junction box (also known as junction box Socket outlet box or junction box - conforming to standards, however, called the installation box ) is used in electrical installations to merge more electrical cables and must comply with standard DIN VDE 0606-1 correspond.
Design and function
In junction boxes, the lines of sockets, lights, switches the sub-distribution and other fixed devices and consumers come together. The lead terminals are respectively connected to the realizable circuit (for example, switch circuit, cross circuit off) with each other. Similar features have also terminal boxes and junction boxes. For connections of conductors in cans are either fixed in position or loose terminals insulated terminals according to DIN EN 60998-2-1 Single (VDE 0613-2-1 ) as screw or DIN EN 60998-2-2 (VDE 0613-2 - 2) as a screwless terminal. In installation boxes ² may be used in accordance with DIN VDE 0606-1, section 4.1.10 (loose isolated ) individual terminals for conductor cross-sections of 1.5 mm ² to 4 mm. At larger cross-sections are to be selected terminals, which are fixed to the junction box in place of the lead compounds.
Junction boxes are available in flush or surface-mounted and cavity-wall construction. Surface-mounted junction boxes are widely used for example in the wet room installation in outdoor areas or in basements. In a domestic environment normally concealed junction boxes are used, which are typically within the installation areas and often near the ceiling.
Installation sockets according to DIN VDE 0606-1 ( section 4.4.1.5. ) Wear inside the can apply the decals on maximum parameters. Led is the conductor cross section (usually 1.5 mm ² and 2.5 mm ² ) with the maximum permitted number of terminals and conductors. Installation boxes in design for equipment installation ( switches, sockets, etc.) is also available in lower construction and thus offer additional space for terminals, which can spare some extra pure distribution boxes.
Robust junction boxes are referred to as terminal box and are used in industrial plant, specialized vehicles, ships, etc., they do not fall into the category of branch and installation doses.
Material
Junction boxes for domestic applications today consist of flame retardant thermoplastic vessel equipped. Previously also bakelite or lined with tar paper sheet was used. Surface-mounted junction boxes for wet room application have grommets for receiving the cable sheaths, partly as before stuffing boxes are used. For exposed areas ( outdoor use, vehicles and vessels ) Junction Boxes are manufactured from die-cast aluminum. These are ( earlier today increasingly uniform metric PG) equipped for cable glands with either glands or threaded.
Terminal blocks
As terminal block, the previously common screw terminal blocks were designated ceramic carrier body. The term was retained in the Duroplasttragkörpern used later and which is partly used also for today's terminal blocks with plastic material carrier.
Often, however, the conductors are connected in a junction box with compression sleeves. This press connections were particularly among aluminum conductors previously used the only reliable type of connection. Aluminum wires provide for repairs is a major problem, although they have grandfathered, but must not be connected to today's conventional terminal blocks. The previously approved for aluminum clamping brackets had lower clamping pressure, but were not reliable. Therefore aluminum conductors are no longer used today. For mixed compression of aluminum and copper conductors, there are special compression sleeves.
Another connection technology are spring-loaded terminal blocks for connecting several individual conductors. Also, they are suitable only for copper conductors.