Terminal blocks are a necessary attribute in the sphereelectrification. Due to their variety, it is possible to flexibly adjust the electrical circuits, closing the windings, by virtue of their uselessness, and disconnecting unnecessary chains.
Terminal blocks are made of dielectrichousing and several mounting screws. In some cases, small metal lamellas are used (they make it convenient to fix the wire in hard-to-reach places).
The terminal blocks are an integral part of the supplyconducting electrical installation and commissioning works. On one side of the terminal board (in accordance with the rules of the PUE) it is allowed to "plant" no more than two wires of the same diameter. Otherwise, the contact will be bad, and the wires simply will not be shaken.
Terminal blocks are often called screwclamping, terminal clamping, terminal clamping, terminal block or terminal block. All this - the names of the same attribute, and a specific name is formed, relying on the location of the terminal strip.
The product allows connectionsingle-core wires with stranded wires. Thus both wires should be fastened from different sides of a box, on different screws. As a rule, the terminal blocks are carbolite, however, this dielectric is quite fragile, so the carbolite was replaced by more reliable plastic analogs. Basically, the products are used for the installation of lighting equipment, household sockets, for connecting the circuits of the power line terminal.
Today there are several types of terminals:
In addition, terminal blocks are available with screw and spring clamps.
Materials for product creation are also usedvarious. Pads are made of polyethylene and are used quite widely. Their feature is the low cost and separation of live parts by physical impact (for example, with a knife). In the body of the shoe, there is a special hole for rigid attachment. Most often in polyethylene pads all current-carrying knots are made of brass, as this is a fairly good and inexpensive conductor.
This product is mainly used forconnection of wires during installation of lighting devices and installation of junction boxes. In addition, the terminal blocks of polyethylene are suitable for the distribution of sockets for household appliances.
Modern terminals are often made ofpolyamide. This material is used in professional equipment, for example, in branded protection terminals or important control boxes for controlling high-voltage equipment.
Polyamide is used in such chains consciously,because these terminals are quite expensive, but high-quality. They are resistant to external influences, and are also resilient and characterized by high electrical resistance. Unfortunately, polyethylene analogs do not.
Polyamide is characterized by high breakdown voltage,a huge resistance to the wandering surface current, a markedly extended range of temperatures at which material can be used. In addition, self-extinguishing is inherent in polyamide terminals, since the material is practically non-combustible, and there are no halogen impurities in the composition.
Typically, the polyamide pads are made with live brass knots, which are covered with a galvanic film.