Various wires and cables are actively used in technology and in everyday life. If it is necessary to conduct electrical wiring in areas with unevenness, then when choosing a conductor, pay attention to flexibility. In such a situation, you can focus on PV 3 1x25. However, other characteristics of the wire also matter. Only after getting to know them, you can understand why this wire is so popular.
Content
- Explanation of the name
- Design features
-
Main characteristics
- Mechanical properties
- Electrical indicators
- Selection recommendations
Explanation of the name
For people whose profession is related to electricity, it is important to understand the labeling of cable and wire products. Important information is included in the name of these products.
The designation of the wire PV 3 1x25 is deciphered as follows:
- P - wire.
- B is the material of the insulating layer, in this case vinyl.
- 3 - flexibility class.
- 1 - single core.
- 25 - cross-section of the current-carrying conductor in mm2.
However, in 2010 a new standard was adopted and the designation of conductors changed. Today the PV brand does not officially exist, and PGV is used instead of this marking.
Thus, the new name means the following:
- Pu - installation wire.
- G - flexible.
- B - vinyl.
In accordance with the new GOST, only one more option can be used as the first letters - Ku. This indicates that the conductor is a cable.
If the wire is not very flexible, then the letter "G" is absent in its designation. As for the designation 1X25, there are no changes here, and such an inscription speaks of the number of current-carrying conductors and their cross-section.
Design features
According to the marking, this conductor has one current-carrying conductor. It is made of several copper wires twisted together. Current-carrying conductor, the cross-section of which is in the range of 0.5-35 mm2, consists of at least seven wires. Conductor flexibility depends on the diameter each individual element. To ensure adequate flexibility, the size of these wires does not exceed 0.79 mm. The use of thinner elements will increase the class of the conductor.
An equally important element of the design of any cable and wire is insulating layer. Everything is quite simple here, and depending on the cross-section of the conductor, the thickness of the insulation is regulated by the corresponding standard. GOST also allows the presence of a two-layer protective coating. In this case, the thickness of the first layer is at least 70% of the total thickness of the entire insulation. In addition, the standard regulates and color of conductors, which can be changed in accordance with the wishes of the customer.
Main characteristics
Each conductor has unique characteristics. They can be divided into two groups - electrical and mechanical. Each of these groups should be considered separately.
Mechanical properties
It should be noted here not only the physical and mechanical properties of the wire, but also several other characteristics. Flexibility is one of the main indicators. According to the labeling PV 3 is a flexible conductor. Its maximum bending radius is at least 10 outer diameters. Keep this in mind when creating electrical routes.
An equally important characteristic of any cable and wire is the operating temperature range. For the product in question, it is from -50 to 70 degrees. However, the installation of the conductor can be carried out only at ambient temperatures from -15 to 35 degrees.
The next important parameter is the incombustibility of the conductor. Some wires not only do not support combustion, but are even self-extinguishing. It is quite obvious that the cost of such products is significantly higher in comparison with conventional ones.
The service life of the PV conductor 3 should also be noted. This figure is 15 years, but if the wire does not interact with air or aggressive media, then it increases.
Electrical indicators
Since PV 3 is a conductor, its electrical characteristics are of paramount importance, and should be remembered when choosing a cable. For any cable, an important parameter is resistancewhich depends on temperature and cross-section of the current-carrying conductor. In accordance with the standard, this indicator is measured at a temperature of 20 degrees.
When choosing a conductor, it is important to consider and cover resistance. It depends on whether he can withstand the operating voltage. At the final stage of production, all wires are subjected to a high voltage test. Moreover, the conditions of this test are also regulated by the corresponding standard. The product is immersed in a container with water and kept in it for 24 hours. After that, the conductors are exposed to a voltage of 2500 V for 3 hours.
Selection recommendations
During factory acceptance, the conductors undergo rigorous testing. The purpose of these tests is to identify non-compliance with mechanical and electrical performance. In addition, it is necessary to carry out periodic tests in order to detect damage in a timely manner.
Among these tests are:
- High voltage tests.
- Determination of the resistance of the veins.
- Bending and impact tests at an air temperature of -15 degrees.
- Heat shock and strength test.
All of them are carried out only by representatives of specialized organizations. The average consumer has less stringent requirements for the conductor.
When choosing a wire, you should check the marking, as well as compliance with the dimensions specified by the seller. You can also set the cable resistance value using a simple multimeter. In addition, it is worth checking the thickness of the protective layer and how easily it is removed.
