Power lines are always open. During the entire period of operation, they are exposed to atmospheric factors. That is why their fastening and installation must be carried out in accordance with the standards. For fastening wires and their insulation, a glass insulator PS-70E is used. It will be discussed in this article.
Application area
Insulators PS-70E are used for insulation and fastening of wires. The latter may include overhead power lines and lightning protection cables. In addition, they are able to hold the switchgear of substations, the voltage at which reaches high values (from 6 to 500 kilovolts). In this case, the products are used in several pieces at a time. They are connected in a kind of garland. They are connected in series by articulation. The number of elements themselves in the garland is determined by various factors:
- voltage value of overhead lines;
- category of the product itself;
- type of support posts;
- the conditions under which the product will be operated.
On poles made of wood, a garland of two insulators is used if the voltage on the line does not exceed 35 kilovolts. At the same voltage value, but on metal supports, a garland consisting of 4 insulators is used. If the voltage of the overhead power line is in the range of 6 to 35 kilovolts, the number of PS-70E pendant glass insulators used does not depend on the height above sea level.
Symbols of insulators and their interpretation
Designations of the PS-70E insulator tell about its main characteristics. The decryption will look like this:
- The letter "P" means that the insulator is suspended.
- The letter "C" indicates the material from which the product is made (in this case, glass).
- The number "70" determines the smallest mechanical load at which the insulator breaks down. Measured in kilonewtons. In our case, it is 70 kN.
- The last letter "E" indicates the modernization of the insulator. Conventionally, it can determine the approximate time of manufacture of the product. The letter "E" indicates that this model is one of the last.
Insulator Properties
PS-70E is characterized by the following indicators:
- The diameter of the product is 255 millimeters.
- The diameter of the rod is 16 millimeters.
- Weight - 3.5 kilograms.
- Type - suspended.
- Under normal operating conditions, the insulator can withstand voltages of 70 kilovolts.
- In conditions of high humidity (in the rain), the product withstands a voltage of 40 kilovolts.
- The minimum breaking load is 70 kilonewton.
The widespread use of suspension insulators is due to the fact that they show better characteristics in comparison with pin products.