power cableHas advantages such as reliable operation, safe power supply, and low maintenance workload. The laying of cables can be divided into direct burial, laying along cable trenches, erecting or hanging along walls and poles, etc. Suitable for places where the installation of towers and wires is not allowed due to safety considerations and environmental constraints. However, once there is a problem with the cable, it will be difficult to locate and handle, resulting in a large amount of work and endangering the safe power supply of the system. Therefore, analyzing various doubts about power cables and actively preventing the occurrence of doubts is essential for the safe operation of the power system.
Fault analysis:
(1) The handling of the contact surface of the connecting fittings is inadequate. Regardless of whether the wiring terminal or the connector is connected, due to the influence of production and storage, there may be impurities, burrs or oxide layers, especially on the aluminum surface, which is prone to form a strong and insulating oxide layer. Only by eliminating these defects can the process quality of cable joints be ensured.
(2) Damage to conductors. The strength of stripping and cutting the insulation layer of a cable is relatively high. Sometimes, a steel saw is used to handle the damage to the conductor, but the damage may not appear severe. However, when the core twists and turns, it will worsen, resulting in a reduced cross-section and increased heat generation.
(3) The wire core is not in place when the conductor is connected. When connecting conductors, the required insulation stripping length is to add 5ram to the depth of the crimping fixture hole, otherwise it will create an empty space at the end of the wire, and only rely on the thickness of the fixture wall to conduct and add heat.
(4) The conductor connection pressure is not good. Some crimping tools and molds cannot meet the requirements, making it difficult to ensure the quality of crimping.
(5) The cable joint was struck by lightning. Some cable joints are not equipped with lightning arresters, resulting in cable joints being damaged by lightning strikes and explosions. Regularly measuring the temperature of the cable joint lead out contact is a useful measure to check the quality of the contact, usually using an infrared thermometer.
Analysis of Preventive Measures:
(1) Establish and improve unified quality standards and specifications for cables and their accessories to ensure control over product quality;
(2) In the production process of cable terminals and intermediate joints, emphasis should be placed on the requirements for sealing and moisture resistance;
(3) Necessary business qualifications and technical training and assessment must be conducted for cable laying construction personnel and cable head production personnel. Personnel without corresponding qualifications are not allowed to carry out cable installation construction to ensure the quality of cable installation;
(4) Strengthen the supervision of construction quality, stop construction operations that do not meet standards, and eliminate behaviors that sacrifice project quality for the sake of rushing for project progress;
(5) Strengthen data management, standardize and complete construction completion drawings, and indicate coordinates, joint methods, quality and technical requirements for intermediate joints to facilitate operation and maintenance;
(6) Strictly control the testing and acceptance, and change the production management mode where construction and testing are completed by the same department;
(7) Strengthen information exchange with the municipal department to avoid damage to power cables caused by excavation, pile driving, and other construction operations;
(8) Strengthen equipment inspection, conduct infrared temperature measurement for cable head production, and regularly maintain cable marker posts, guardrails, etc;
(9) Carry out cable pre testing work in conjunction with the planned power outage.
Anhui Huarun Instrument Cable Co., Ltd., founded in 1996, is a comprehensive enterprise integrating electronic equipment. Covering an area of 68000 square meters. The company is located in the conveniently accessible Tongcheng Industrial Park, with beautiful terrain and environment. It borders the ancient city of Yangzhou to the east and the historic city of Nanjing to the south in the metropolitan area. We are a specialized company engaged in the research, development, production, and sales of instruments, cables, and rubber products. The company has strong technical development capabilities and gathers talents from the wire and cable, instrument, rubber and plastic, and electronic equipment industries. Its main products include thermocouples, thermistors, bimetallic thermometers, pressure gauges, pressure transmitters, high and low temperature compensation wires, high temperature cables, power cables, control cables, flame-retardant cables, silicone rubber cables, signal cables, heat tracing cables, intrinsic safety cables, computer cables, rubber products, electronic equipment, and complete sets of automation instruments and meters.