High voltage cable is a kind of power cable, refers to the transmission of 10KV-35KV (1KV=1000V) between the power cable, more should be used for power transmission of the main road.
Types of high voltage cables
The main types of high voltage cables are YJV cable, VV cable, YJLV cable, VLV cable.YJV cable full name crosslinked PE insulated PVC sheathed power cable (copper core).PVC insulated PVC sheathed power cable (copper core), VV.YJLV cable full name crosslinked PE insulated and PVC sheathed power cable VLV cable full name PVC insulated PVC sheathed aluminum core power cable.
Structure of high voltage cables
Part from the inside to the outside of the high-voltage cable comprises a conductor, insulation, inner protective layer, filling material , external insulation. Of course, armoring high-voltage cable is mainly used for underground, can resist the compression of high intensity on the ground and prevent damage to the other forces.
Characteristics of high voltage cables
The product is suitable for AC rated voltage 35kV and below for transmission and distribution can be fixed granary design lines, cable conductor of the highest long-term working temperature of 90 degrees, short circuit (the longest time is not more than 5S), the highest temperature of the cable conductor does not exceed 250 degrees.
High voltage cables fault reason
The cable is a bridge between the power supply equipment and the power supply equipment. Widely used, so fault often happens, below is a brief analysis of the common problems of the high voltage cable, produced according to the fault classification is divided into the following categories: manufacturing reasons, construction quality, design unit design reasons, external damage four categories.
Because of the construction quality leads to high voltage cables system failure in many cases, the main reason is the following several aspects: one is the site conditions are relatively poor, cables and connectors in the manufacturing plant environment and process requirements are very high, and construction temperature, humidity and dust in the field are not good control. Second cable construction process on the insulation surface will inevitably leave tiny scratches, semi conductive particles and emery cloth sand also may embedded in insulation and joint construction process due to insulation exposed in the air, insulation will also absorb water. All of these long-term safe operation to stay hidden. Three is not installed in strict accordance with the process of construction or process does not take into account the possible problems. Four is completed and accepted by the DC voltage test result in the formation of the joint inside the electric field leading to the formation of the insulation damage. Five is due to poor seal processing. Intermediate joints must be the metal copper shell plus PE or PVC insulation coating sealing structure, in the construction site to ensure sealing compacting, so effectively ensures the joint sealing and waterproof performance.