In daily operation, the contamination of the surface of the porcelain sleeve of the arrester should be checked, because when the surface of the porcelain sleeve is seriously contaminated, the voltage distribution will be uneven. In a lightning arrester with parallel shunt resistors, when the voltage distribution of one of the components increases, the current through the shunt resistor will increase significantly, and the shunt resistor may be burned out to cause a malfunction. In addition, it may also affect the arc extinguishing performance of the valve type arrester. Therefore, when the surface of the arrester porcelain sleeve is seriously filthy, it must be cleaned in time. Check the lead wire of the arrester and the grounding down conductor. There are burn marks and broken strands, and whether the discharge recorder burns through this aspect. It is most easy to find the invisible defect of the arrester; check whether the seal at the upper end of the arrester is good, and the seal of the arrester will be bad. If the water entering the water is easy to cause an accident, check whether the cement joint between the porcelain sleeve and the flange is tight. Install a waterproof cover on the lead of the 10 kV valve arrester to prevent rainwater from penetrating; check the arrester and the protected electric Whether the electrical distance between the equipment meets the requirements, the arrester should be as close as possible to the protected electrical equipment. The arrester should check the operation of the recorder after the thunderstorm. Check the leakage current. If the power frequency discharge voltage is greater than or less than the standard value, it should be repaired. And test; when the discharge recorder has too many movements, it should be repaired; there is crack in the porcelain sleeve and cement joint; when the flange and rubber mat are off, it should be repaired. The insulation resistance of the arrester should be checked regularly. The 2500 volt insulation shaker is used for the measurement, and the value obtained from the side is compared with the previous one. If there is no significant change, the operation can be continued. When the insulation resistance drops significantly, it is usually caused by poor sealing and moisture or short circuit of spark gap. When it is lower than the qualified value, it should be tested for characteristic. When the insulation resistance is significantly increased, it is generally due to internal parallel connection and poor contact resistance. Or breakage and spring slack and separation of internal components. In order to detect invisible defects inside the valve arrester in time, a preventive test should be conducted before the annual thunderstorm season. Valve type arrester installation 2. The arrester should be installed vertically, not tilted, the leads should be connected firmly, and the terminals on the arrester should not be stressed. 3. In order to prevent its normal operation and failure after lightning strike, affecting the normal operation of the power system, the lightning arrester installation position should be within the protection range of the drop-out fuse. 4. The lead wire section of the valve type arrester should not be less than: copper wire 16 square millimeters; aluminum wire 25 square millimeters. The grounding down conductor and the metal casing of the protected equipment should be reliably connected to the grounding grid, and the grounding resistance should be no more than 5Ω. Fault handling of valve type arrester Valve type arresters often have abnormal phenomena and faults during operation, and should analyze and judge abnormal phenomena, and take measures to deal with faults in time. 1. The weather is normal and the arrester is found If the porcelain sleeve has cracks, it should be stopped immediately. The faulty phase arrester will be taken out of operation and the qualified arrester will be replaced. In the thunderstorm, the porcelain sleeve was found to have cracks, and its operation should be maintained. After the thunderstorm, it was treated. If the flashover is caused by the crack of the arrester porcelain sleeve, but the system is not grounded, the faulty phase arrester should be deactivated under possible conditions. 2. The inside of the arrester is abnormal or the casing is broken. This phenomenon may cause system ground fault. When handling, personnel should not be close to the arrester. The fault arrester can be disconnected by circuit breaker or manual ground transfer. 3. The arrester suddenly exploded during operation. In this case, if the system has not been permanently grounded, after the thunderstorm, open the faulty phase isolation switch to disable the arrester and replace the qualified arrester in time. If the system has been permanently grounded after burning, it is forbidden to use the operational disconnector to deactivate the fault arrester. 4. The lightning arrester action indicator burns black or burns inside, the grounding lead line connection point is blown, the arrester valve resistance is invalid, the spark gap arc extinguishing characteristic is deteriorated, and the power frequency freewheeling is increased. If any of these abnormal phenomena are present, it should be timely The arrester is used for electrical testing or disintegration inspection. Butt Connector,Lugs Insulated Female Connectors,Insulated Female Connectors,Non-Insulated Spade Terminals Wire Connector Taixing Longyi Terminals Co.,Ltd. , https://www.lycopperlugs.com
1. The installation position of the valve type arrester should be as close as possible to the protected equipment. The maximum electrical distance between the arrester and the 10 kV transformer: the single-line incoming line that is frequently operated during the thunderstorm season should be less than 15 meters, the two-way incoming line is less than 23 meters, and the three-way incoming line is less than 27 meters. If it is greater than the above distance, it should be on the busbar. Set valve type arrester.