Cable lines tests, both at the assembly stage and during operation, are a key element of ensuring reliability and security of power systems. In this article, we will focus on measuring cable lines, focusing on procedures, qualification requirements and the importance of diagnostic tests.

Who has the right to measure the power line?

The most important thing is, of course, who at all has the right to conduct such measurements. Knowledge and experience are needed here, as is the use of professional equipment, such as a cable bristle trailer. Conducting research requires cooperation of the entire team:

• Recommender: a person with a qualifying certificate in a supervisory position. He is authorized to make decisions regarding work, identify threats and determine protective measures.
• Coordinating: is responsible for coordinating work related to the movement of power equipment.
• Allowing: authorized to be actions related to admission to work. He is responsible for the preparation, transfer of the work zone, completing the activities and the liquidation of the work zone.
• Team driver: Responsible for the implementation of activities related to the commencement and performance of operational works. It is also trained in the area of instruction on the performance of work, work at height and providing premedical first aid.
• Team member: The person responsible for performing work in accordance with the regulations and safety rules. It also has qualifications in the field of instructions for performing work, work at height and providing pre -medical first aid.

 

The use of these rights is aimed at ensuring safe and coordinated activities related to measuring the power line, and maintain the highest safety and quality of work standards. This is important not only when laying cable lines, using equipment such as rollers for unwinding cables, but also during operation and checking of the technical condition.

Conducting tests of cable lines

Cable lines tests are a key stage in maintaining their reliability and safety. They are divided into two main categories: basic and diagnostic tests. Cable works contractors are responsible for conducting basic tests, especially in the context of the construction, reconstruction or renovation of medium voltage cable lines (SN).

 

Diagnostic tests are aimed at providing detailed information on the technical condition of cable insulation and cable accessories. Their conduct allows you to construct an effective preventive system, minimizing the likelihood of failure. In addition, it enables planning of cable modernization, which translates into improving reliability indicators, as well as reducing operating costs and investment outlays. At the stage of laying cable lines, equipment such as cable scissors is used, but this does not replace further maintenance.

Basic tests on cable lines

When conducting basic tests on cable lines, the key aspect is to measure insulation resistance. Before taking this measurement, the outer surfaces of the heads should be carefully cleaned, maintaining the techniques indicated by the manufacturer. The cable with the equipment should be discharged and grounded before each measurement, lasting at least 1 minute. Measurement of insulation resistance should include any cable vein in relation to the screen and the return vein. Using a 2.5 kV insulation resistance meter, resistance values for 1 km long -length lines should not be lower than 100 mΩ for polyethylene insulation cables (XLPE, PE) and 50 MΩ for cables with paper insulation saturated with synovium (Pilc). For other cable lengths, the measured insulation resistance should be converted into 1 km long cable.

 

In subsequent stages of basic research, it is necessary to measure the continuity of working and return veins, aimed at checking the correctness of vein connections. This measurement is recommended for both new lines and after repair. In addition, the main insulation test should be performed, adapting the parameters to the specifics of a given system. Also, the tension test of the outer shell of plastic cables is an extremely important element of tests, requiring special attention during the diagnostic process. Checking phase compliance, although carried out after attachment, is an important stage that requires precise verification to ensure the correct functioning of the cable line.

 

To determine whether the cable line works properly, it is necessary to conduct appropriate tests. They must be carried out according to the instructions, because otherwise their results will not be reliable.