Q: how can film capacitors prevent failure?
A: even if it is a good film capacitor quality permanent also hard to avoid can appear a few problems, as long as we understand the capacitor failure preventive measures, can effectively increase the service life of the film capacitor.
1. Deal with abnormal operating conditions in a timely manner, and in the operation, it is found that there are abnormal conditions such as bulging tummy, joint heat and serious infiltration (leakage) oil, etc., which must be withdrawn from operation. In case of any serious accident, such as oil injection, fire, explosion, etc., the power failure inspection shall be conducted immediately, and the new capacitor shall be replaced after the cause of the accident is determined.
2. Strictly control the running voltage, and the running voltage of the shunt capacitor must be strictly controlled within the allowable range. The long running voltage of the parallel capacitor shall not exceed 10% of the rated voltage value, and the running voltage is too high, which will greatly shorten the service life of the capacitor. With the increase of operating voltage, parallel capacitor dielectric loss will increase, temperature rise, the capacitor to speed up the capacitor insulation aging, capacitor inside insulation breakdown and premature aging, damage. In addition, under high operating voltage, the insulation medium inside the capacitor will have local aging, and the higher the voltage, the faster aging and the shorter life.
3, installing fuse protection, respond to every single capacitor set the fuse protection, claim the protection of the rated current of the fuse shall not be greater than was 1.3 times rated current of the capacitor, which can avoid a capacitor failure occurs, caused by not timely removal of explosion accidents.
4, correct selection (cut) switch, disconnect the parallel capacitor, as a result of the switch between static and dynamic contact arc, will cause the operating overvoltage generation, in addition to the claim will be (cut) switch capacity to choose better than parallel capacitor group of large capacity by about 35%, also must be a contact between the insulation recovery high strength, small arc reigniting sex, the circuit breaker arcing good performance.
5, and control the operating temperature, under normal circumstances, the general requirements parallel capacitor shell's hot spot temperature shall not be greater than 60 ℃, otherwise, must find out the reason, for processing.
6, strengthen patrol, inspection, maintenance, shunt capacitors should be regularly check the blackout, at least 1 time every quarter, mainly check the capacitor shell, porcelain bushing, mounting bracket parts such as dust and dirt does exist, and cleaning seriously. Special attention should be paid to whether the joints of the joints are strong and loose. Whether the shell is bulging or leaking oil, etc. If any of these phenomena occur, the capacitor must be withdrawn and handled properly.