Cable tests in cable lines are an integral part of the maintenance and operation of electrical infrastructure. Regular tests and cable inspections are aimed at detecting potential faults, assessing the technical condition and prevent failures that could lead to interruptions in the supply of electricity, and in extreme cases - to fire hazards. Safety rules when conducting such tests are crucial for the protection of employees, equipment and infrastructure itself.
Tests of cable cable and accessories
Cable cable and accessories attempts are a key element to ensure their reliability and operational safety. Cable tests, muff and heads specific to the standards should be carried out in accordance with relevant standards, such as the IEC 60502-2, PN-HD 620 S2, PN-EN 60228, PN-HD 629-1-S3, PN-HD 629-1-S3/A1, and PN-EN 61442. The scope of these tests Tests must be performed by accredited research units. The accreditation of these units is broadcast by national accreditation units in accordance with the Regulation of the European Parliament and of the Council (EC) No. 765/2008 of July 9, 2008.
The results of these tests are documented in reports that must be provided in Polish or as a translation into Polish, in paper or electronic form. These reports should contain all necessary data for assessing the methodology of the tests and the results obtained, both in the field of electrical and non -electrical tests. All trials listed in the standard are implemented at the cost of the first contractor, which ensures that the testing process is an integral part of the project, thus increasing the safety and reliability of cable lines. It is also necessary to run a line in accordance with the provisions, including To make connections, it is necessary for such equipment as hydraulic clamp.
Cable production tests used
The cable production tests used are key to ensuring their quality and reliability, as well as to detect all material and assembly defects that may occur at an early stage of operation. These tests must be carried out on each factory section of the cable, in accordance with the scope and methods specified in the relevant standards. The purpose of these tests is to confirm that all the characteristics and rated parameters of the cables meet the requirements of the specification. One of the key tests is an attempt to insulate alternating voltage (AC), which involves applying a 3.5U0 voltage with a frequency of 50 Hz for 5 minutes on each cable vein. Lack of piercing during this sample is a criterion confirming the integrity of insulation and its ability to withstand operating voltages. This type of rigorous tests are necessary to ensure that the cables will be safe and reliable in long -term operation.
What are the control tests of the cable line?
Cable line tests play a key role in ensuring that the installed cable meets all quality and safety requirements. This also requires checking of connections made with such devices asclamp. The first step is to check the sequence of phases and continuity of working and return veins, which can be carried out using a solid current with a voltage not exceeding 24 V.
Then you need to try the tightness of the coating of the located cable, using a voltage test worth 5 kV, which should be performed for 5 minutes without puncture and jump. The next stage is the voltage test of the main insulation, which includes measuring incomplete discharges and a dielectric loss ratio. This test can be performed with a sinusoidal alternating voltage or alternating voltage of cosine -rectus during the methodology used.
In addition, insulation resistance is measured using a 2.5 kV insulation resistance meter, where the measured resistance value should not be less than 100 mΩ for polyethylene insulation cables (XLPE, PE), with a line length of 1 km. These controlling procedures are necessary to ensure the reliability and safety of the cable line during operation.
Basic and diagnostic tests of cable lines
Basic and diagnostic tests of cable lines are a key element of management and maintenance of power infrastructure. Despite the use of security such asCable, over time, the lines are naturally worn and damaged, so it is necessary to control their technical condition.
The tests are classified in two types: basic and diagnostic. Primary tests should be entrusted to the contractor of cable works or the appropriate cells dealing with operational works as an integral part of the process of construction, reconstruction or renovation of medium voltage cable lines.
On the other hand, diagnostic tests are aimed at providing information necessary to diagnose the technical condition of the insulation of cable and cable accessories. Thanks to these studies, it is possible to develop effective preventive measures to reduce the risk of failure and planning modernization, which contributes to improving the rates of network reliability and reduction of operating and investment costs. Performing diagnostic tests should be entrusted to specialized executive cells, equipped with appropriate equipment and with necessary knowledge and experience. These tests should be carried out for both newly built and rebuilt cable lines, as well as in the case of existing installations, in accordance with specific procedures and recommendations.
For newly built or rebuilt cable lines, diagnostic measurements should be made before connecting cables to the power network and attaching the line under voltage, except for certain cases. By conducting these tests, you can not only ensure the safety and reliability of electrical infrastructure, but also the optimal use of resources and minimizing the risk of failure.
