Vacuum circuit breaker current in industrial production and distribution are widely used, the most common products such as VS1-12 vacuum circuit breaker, but due to their work high rated voltage, current, fox ability, lead to the existence of many problems and hidden dangers, a single handle properly, it may lead to many accidents. Therefore it requires us in vacuum circuit breaker selection, installation, operation, maintenance process to strengthen management, to run the vacuum circuit breaker status monitoring and diagnosis of the common faults, can be timely and accurate processing of.

1, commissioning and acceptance test of strict equipment debugging and commissioning test, to prevent the equipment in the transport of the change and adjustment after the emergence of the phenomenon is not complete, especially the operating mechanism of vacuum circuit breaker and connection problems. The main complex parameters: bounce, tripping over the same period, distance, compression stroke, and closing speed and time, DC resistance, switching operation voltage value, fracture insulation level, drive test, these parameters should meet the requirements. In our usual routine maintenance work, mainly found the following problems: circuit breaker cabinet static contact in a telescopic baffle plate and a handcart type circuit breaker framework jam caused by feeding difficulties, breaker bouncing and travel is not qualified, the circuit breaker body insulator porcelain insulator with rod distance too close shot bad, bad closing contactor operation characteristics, tend to move after one cannot move or action electric pressure gradually increased, vacuum tube vacuum degree does not meet the requirements, we on these issues have made a deal. On commissioning and acceptance test of vacuum circuit breaker must be strictly. We want to find pieces of insulation breakdown, mechanism anomaly, vacuum arc extinguish chamber leakage and bouncing, velocity, stroke abnormal failure, and handle well before operation, to ensure the safe operation.

In 2, operation and maintenance, regular inspection

2, 1, operation and maintenance operation of observe no abnormal phenomenon, such as on the breaker, whether there are abnormal discharge sound, power transmission, observation of a vacuum arc-extinguishing chamber has no cracks, breakage. Abnormal findings report immediately, to be confirmed after the overhaul, and then carry out the operation.

In 2.2, regularly check the vacuum breaker body defects : vacuum interrupter body insulation breakdown, leakage, overvoltage protector of unqualified, vacuum interrupter resistance failed, the new input breaker rejecting and breaking phenomenon. Regular test, vacuum measurement, DC resistance and on-off action voltage value of the defect is found an important means of.

In 3, a vacuum circuit breaker status monitoring and diagnosis

The vacuum arc-extinguishing chamber is the vacuum circuit breaker is the key component, which is made of glass or ceramic support and seal, with the moving and static contacts and a shield cover, the vacuum degree of not less than 6.6 x 10-2P a. The new factory for the manufacture of vacuum arc extinguish chamber to reach 7.5 x below 10-4Pa. When the vacuum degree is reduced, the interrupting performance decreased. So the vacuum arc extinguish chamber cannot be affected by any external force or collided.

In 3.1, the vacuum interrupter check vacuum circuit breaker is characterized by a contact seal in vacuum interrupter insulating casing, in the strict quality management using modern equipment and manufacture, to ensure long life. In the following case need to be checked, if necessary

Need to replace the vacuum bubble:

( I ) vacuum interrupter has reached the factory guarantee the on-off times ( when the mechanical life of I million times );

( 2) vacuum interrupter has reached the designated inspection cycle ( points, closing times reach I million, short-circuit current of 100 times, for arc extinguish chamber pressure test, up to 20000 times when replacing the vacuum interrupter );

( 3) the appearance of unusual. Basis of inspection: the life of vacuum circuit breaker is composed of contact and vacuum degree 2 indicators to judge:

( 1) determination of wear of the contact. The vacuum circuit breaker contact rod engraved markers to check or use vernier caliper to determine contact overtravel. If the dynamic, static contact cumulative wear thickness is outside the specified range, indicates that the vacuum bubble electric life has ended, should replace the vacuum bubble.

( 2) a vacuum bubble DC resistance within the prescribed scope. A vacuum bubble DC resistance is less than 25 μΩ, vacuum circuit breaker conductive loop resistance is less than 45 μΩ

( 3) vacuum degree measurement.

①industrial frequency withstand voltage method. So that the circuit breaker is in the disconnected state, in vacuum interrupter contacts with voltage to determine the tolerance, 42kV, Imin industrial frequency withstand voltage test, the vacuum tubes should not be sustained discharge, is considered normal.

The vacuum degree tester. The more precise method is applied to the magnetron, manufacturing plant for vacuum arc extinguish chamber test. Vacuum degree greater than 5*10-4Pa,

③spark meter method. Only applicable to glass tube with vacuum interrupter, when in use, make spark leak detector in the arc chamber surface moves, in the high frequency electric field have different internal lighting situation. If the inner tube has a pale blue glow, the vacuum degree in 1.33*10-5 above; if it was red and blue light, illustrate pipes have failure; such as the pipe in atmospheric condition, is not light.