CKJ5-125/1.14

Yueqing public Yao Electric Switch Factory Tel :0577 -62,906,628 Fax 577 -62767956 Mobile: 18205877547 vacuum circuit breakers technical indicators o ● Ambient temperature: maximum ambient air temperature does not exceed + 40 ° C, and the average of 24 hours does not exceed + 35 ℃, the lowest ambient air temperature not lower than -15 ° C. ● Altitude: The altitude of the installation site for the low voltage components in the low-voltage class components and high-pressure switching element does not exceed 2000 meters, switching elements for high-pressure class over 1000 meters. ● Relative humidity: relative humidity of the atmosphere in the ambient air temperature of + 40 ° C when not more than 50 [%] at a lower temperature allows a higher relative humidity, daily average of less than 95 [%], the wettest month the average temperature of + 20 ° C when the monthly average maximum relative humidity of 90 [%] have taken into account due to temperature changes in the surface of the condensation product. ● Working environment: rain and snow hit, the risk of fire, explosion, chemical corrosion and strong vibration of the occasion. ● Pollution degree: II-level, non-conductive pollution. o In recent years, with the continuous construction and development of the grid, all kinds of voltage quality and supply reliability of a higher demand. Vacuum circuit breaker interrupter ability, long electrical life, on-site maintenance, high technology content, in the power systems up to 35kV voltage level is widely used. Vacuum circuit breaker has universal application, some issues still need to take good care of proper treatment, can only be assured of safe and stable operation of the power system. Timely find out the point of failure of the vacuum circuit breaker, take active preventive measures, to improve the reliability of the power grid is helpful. Is combined with vacuum circuit breaker failure Shixing Power Supply Bureau recently discovered together for a brief analysis. 1 fault found at 9:10 on April 8, 2007, the the Shixing Power Supply Bureau, an 110kV integrated automation substation in the shift routine patrol equipment and found that abnormal sound 35kV321 vacuum circuit breaker "creak" sound intermittently, after further observation, confirmed C relative to the issue of the sound. Duty infrared thermometer check the C-phase electrical connection point, the TA and the circuit breaker body temperature of about 16.5 ° C, the circuit breakers are ambient temperature, visual inspection did not find other abnormalities. After 321 vacuum circuit breaker from the grid splitting out of operation, at the same time inform the engineering and technical personnel to the scene to conduct investigation and testing to ensure the shortest possible time to deal with failure, normal power is restored. Failure analysis of the 2.1 visual inspection and vacuum test the vacuum circuit breaker model ZW7-40.5 built-LZZBJ4-35 current transformer, put into operation in June 2005. We first insulation resistance, the vacuum degree of the vacuum circuit breaker contact resistance test results show that the vacuum circuit breaker vacuum interrupter, the lower end of the insulating sleeve, built-in current transformer insulation resistance and the degree of vacuum, the contact Resistance is also qualified. As can be seen from the result of the detection of the infrared thermometer, an electrical connection point contact is good, no fever phenomenon. Breaker insulated rod, horizontal rod, box, we continue to check and found no fracture, corrosion, discharge, broken off, foreign body or parts fall off, fixedly connected to some of the components are not loose, either insulated or damaged, defaced gasket unaged, current transformer core silicon steel screws on tight. Issued by the vacuum circuit breaker intermittent "creak" abnormal noise is a current transformer secondary circuit open or cable due to the loose? Conduct the multiple manual closing operation of the test, the circuit breaker to trip-free test the electric sub closing operation test, the circuit breaker is not abnormal, spring operating mechanism of the circuit breaker and mechanical drive should not be a problem. 2.2 pressor test in order to pinpoint the vacuum circuit breaker C issued specific location of the abnormal noise, follow do not expand the scope of damage, do not exacerbate the principles of equipment damage, in the case of the circuit breaker, single-phase sub- 22.5kV rated voltage is applied to the test and found no abnormal noise. To truly reflect the failure to find as soon as possible to issue the specific location of the abnormal noise, no-load power transmission circuit breaker (ie only together on the bus side isolation switch and circuit breakers), after about 4min C phase finally appeared intermittent "squeak squeak "sound of the discharge, between the for specific sound insulating sleeve in the lower end portion and the current transformer, the casing current transformer sound is particularly evident, but with the passage of time discharge louder, like feeling at all times possible occurrence of breakdown. The degree of vacuum test can not replace frequency voltage withstand test. The degree of vacuum test due to the limit of the test range, with the power frequency voltage withstand test in order to make an accurate diagnosis of the vacuum interrupter. Especially for vacuum bubble completely leak test values ??with a good degree of vacuum when the value is close to easily cause misjudgment.