Terminal box: purpose, description

More than a hundred years ago, with the introduction of electricity in everyday life, humanity finally took the technogenic direction of our civilization. Now we are surrounded by various electrical appliances and equipment. Almost every house has electric wires, and if housing is in hard-to-reach areas, then people find a way out of the situation: install wind generators, solar panels and so on. But not all people know that almost any electrical appliance needs an element such as a terminal box. What is it and what is it for? In this article we will try to answer these questions.

The terminal box is a rectangular or round box with a terminal block inside. Typically, the shoe is designed for a maximum cross-section of a commutated wire (35 mm) and for the number of direct connections - 7-12 pcs.

The terminal box, depending on the purpose, can be:

• For dry rooms;
• For objects with an aggressive environment (chemical production);
• For outdoor use (temperature and moisture resistant).

Classification of terminal boxes

1. The mounting method is:

• For open installation;
• For concealed installation in concrete;
• For concealed installation in plaster, drywall.

2. Depending on the materials used:

• From polypropylene, АВС-plastic, PVC self-extinguishing, etc .;
• From metals.

3. By degree of protection (dust, moisture, etc.):

• IP20 boxes;
• IP44, IP54, IP65;
• Explosion-proof.

4. Divided according to climatic performance:

• For external use V1;
• For placement under the canopy of U2;
• For premises Y3.

5. Depending on the form of performance are:

• Rectangular;
• Square;
• Round.

6. By the presence of terminal blocks:

• With terminal blocks;
• Without terminal blocks.

Also mention should be made of the instrument boxes. They are somewhat larger in overall dimensions than the terminal boxes. Allow to place in itself except the pads small appliances, switches, sockets.

The terminal box can have in its housing hermetic glands for the supply of wires and cables. Omentums are often replaced by metal or plastic pipes. Seals can be rubber with cut concentric circles or plastic, allowing you to adjust the mounting hole. The use of oil seals can significantly improve the leaktightness of the product. The box is closed with a lid, which is fixed to the body with screws or latches with gaskets.

All terminal boxes, depending on the purpose, application and design, have different markings. This allows the consumer to quickly select the desired product. After all, the terminal junction box can be used both under water and at a height (say, five thousand meters above sea level), can be protected in the wall, and can be constantly exposed to aggressive influences in the chemical industry. All this information is contained in the product code. For example, the explosion-proof terminal box is marked with 1ExeIIT5. There are many types of markings, even among explosion-proof boxes. In the marking, information is also encrypted about the degree of explosion protection, and the place of application of the product, and much more.