What is MKESH cable: design features, main parameters of the wire

Cable products are one of the most demanded products, as they are used in many areas of human activity. One of its representatives is MKESH wire, which is most often used to connect electronic and radio equipment, as well as connecting the switching part of the automatic telephone exchange (automated telephone stations).

Explanation of the abbreviation

MKESH is a generalized marking of this series of cable products, where

• M - the area of ​​use of the cable, that is, the performance of installation work;
• K - the presence of an insulating layer made of nylon;
• E - the presence of a protective screen;
• Ш - designation of the outer shell. In this case, a PVC hose.

In the current catalogs and reference books of cable products, generalized marking is not used; to the right of it, digital designations are required, for example, MKESH 14 × 0.75. The number 14 in this case indicates the number of cores, and 0.75 is the designation of the cross-section of the copper wire used when twisting it.

Design features

The basis of the cable is made up of conductive cores, the number of which can be from 4 to 14 pieces. The cores are structures of several twisted wires, placed in external insulation - usually polyvinyl chloride, which is highly resistant to drops temperatures.

On top of the core (the interweaving of the veins), a film of synthetic materials is applied, on which a screen is created - an interlacing of a thin bare copper wire. The screen protects the cable from interference and the effects of various electromagnetic interference. It also ensures stable quality of electric current transmission and high product reliability.

Main characteristics

Among all the performance characteristics of cable products the most relevant for the MKESH series are the following parameters:

• the minimum bending radius, which should be equal to 5 outer diameters of the wire;
• linear resistance of the cable - 0.1 Mohm / km when operating the line in an environment up to + 20 ° C;
• the possibility of laying both in one line and in a bundle with other cables;
• large construction length - more than 25 m;
• high resistance to shock and mechanical stress;
• long service life - 15 years.

Along with good performance MKESH series products have a number of limitations, which appear during operation and installation work:

1. MKESH cable can be used in the temperature range from -50 ° C to + 50 ° C, with air humidity less than 98%.
2. The maximum allowable voltage depends on the type of current flowing in the system: with direct current - up to 0.7 kV, and with alternating current - up to 0.5 kV, with a frequency of 0.4 kHz.
3. Products of the MKESH series are subject to prolonged heating of an individual core, which is normal, until it reaches + 70 ° C, which, according to the tolerance, is a critical value.

Features of cable installation

One of the advantages of the MKESH series is that it can be laid in cable ducts, pipes, wells and other linear structures together with cables for other purposes. This advantage is relevant for enterprises with limited space, where there are no possibilities for laying separate lines.

Internal (copper) and external (polyvinylchloride) screens protect MKESH from interference of electromagnetic radiation and other interference emanating from other cables. They also provide reliability and uninterrupted transmission of control signals.

But screens alone are not enough to provide the required transmission quality; for this, it is necessary to carry out installation work in accordance with the rules. Previously, they were carried out as follows: the ends of the wires were taken and soldered to the contacts of the cross-section or distribution cabinet. And now this is done using crossover pads.

Each end is designed to provide signal path to a separate piece of equipment. The terminals on the jumper block are color coded to match the core color. After connecting all ends to the appropriate terminals, close the shielding copper sheath to the earthed enclosure of the rack-type or cabinet-type equipment. Moisture protection is ensured by terminating the cable on both sides.

Cable cost

Before purchasing cable products, including a representative of the MKESH series, you should focus on the following factors:

1. Number of lived. For example, to control a video surveillance system consisting of three cameras, you need to use a cable that consists of more than 4 cores.
2. Cable cross-section: up to 0.5 mm for secondary circuits of low-current systems controlled by powerful magnetic starters, and from 0.75 mm if controlled by an electric motor.

The cost of the cable varies from 13.85 to 96.65 rubles per 1 m and depends on the number of cores and their cross section.