In the daily operation of the power system, it often affects the normal operation of the cable due to the quality of the power cable itself, improper construction and unreasonable operation and maintenance. The following are the common line problems and faults in the use of the power cable. analysis.
Common line faults
Short-circuit fault : There are two-phase short-circuit and three-phase short-circuit, which are mostly caused by hidden dangers left in the manufacturing process.
Grounding fault : A certain core or several cores of the cable break down to the ground. The insulation resistance is lower than 10kΩ and the low resistance is grounded. Above 10kΩ is called low resistance grounding. Mainly due to cable corrosion, lead cracks, insulation dryness, joint processes and materials.
Broken linear fault : one core or several cores of the cable are completely or not completely broken. Cables can be disconnected due to mechanical damage, terrain changes, or short-circuits.
Hybrid fault : Two or more of the above faults.
Causes and Countermeasures for Power Cable Line Failure
External force damage : In the process of storage, transportation, laying and operation of the cable, external force damage may occur, especially the directly buried cable that has been operated, which is easily damaged in the ground construction of other projects. Such accidents often account for 50% of cable accidents. In order to avoid such accidents, in addition to strengthening the quality of work in cable storage, transportation, laying and other aspects, it is more important to strictly implement the ground-breaking system.
Corrosion of protective layer : Electrochemical corrosion of underground stray current or chemical corrosion of non-neutral soil invalidates the protective layer and loses the protection of insulation. The solution is to install the drainage equipment in the stray current dense area; when the local soil on the cable line contains the chemical substances that damage the cable lead package, the cable should be installed in the tube and the neutral soil should be used as the cable gasket. And cover, but also asphalt on the cable.
Overvoltage, overload operation : improper selection of cable voltage, sudden high voltage intrusion or long-term overload during operation may damage the insulation strength of the cable and break down the cable. This requires strengthening inspections and improving operating conditions to resolve them in a timely manner.
Outdoor terminal head soaking water : Due to poor construction, the insulating glue is not filled, causing the terminal head to be immersed in water and eventually exploding. Therefore, it is necessary to strictly implement the construction process regulations, carefully check and accept; strengthen inspection and timely maintenance. The oil leakage of the terminal head destroys the sealing structure, so that the impregnating agent at the end of the cable is lost, the thermal resistance is increased, the insulation is accelerated and aged, and the moisture is easily absorbed, resulting in thermal breakdown. It is found that the patrol should be strengthened when the terminal head leaks oil, and should be redialed when it is serious.
Concerned about surprises
Label: terminal head power cable two-phase short circuit power system common fault
Previous: 12 types of parts usually included in fasteners Next: China's hardware safety locks purchase and daily maintenance knowledge
- Bluetooth wireless
- Built-in speaker
- Built-in microphone
- Handsfree speakerphone
- Supports profile A2DP (Advanced Audio Distribution Profile)
- Aux in (3.5mm audio input)
- Micro-USB port for battery recharge
- Wireless range: 10 meter
- Controls: volume up, volume down, play/pause, pairing/answer phone
- On/off switch
- LED pairing indicator
- DC battery power: built-in rechargeable battery
- Battery life: ~5 hours at 100% volume
- Dimensions:Diameter 115mm*Height 145mm
- Includes: Micro-USB cable, Aux plug,
Bluetooth Speaker,Portable Bluetooth Speaker,Mini Bluetooth Speaker,bluetooth Wireless Speaker,portable wireless speaker
Shenzhen Lanejoy Technology Co.,LTD , https://www.wire-spring.com