Fault Diagnosis of Vacuum Circuit Breaker
In use, maintenance, maintenance of new vacuum circuit breakers may feel difficult, especially once a fault, it may do nothing. For this phenomenon, describes the newest on the market made by vacuum circuit breaker modules and fault diagnosis.
As a new vacuum circuit breaker switch, and the previous breaker, magnetic circuit breakers and other than blowing a lot of strange places, especially in recent years, the latest foreign influx of vacuum circuit breakers and domestic manufacturers continue to introduce new , such as the vacuum circuit breaker structure compared with the previous, major changes have taken place. Actually, no matter what form of vacuum circuit breakers, are similar to the basic working principle, this paper analysis of vacuum circuit breaker failures and conclude and to make the complex seem to have become rule-based troubleshooting.
1 circuit breaker modules
Vacuum circuit breakers should function as electrical switches are: ① accurately closing, ② to switch reliably maintained in the closing position, ③ accurately sub-gate, ④ reliably keep the switch OFF position, ⑤ correct implementation operating procedures and the issue of switching signals (including the indication signal, control signal and the signal chain.)
Structural analysis during the vacuum circuit breaker, no matter what kind of structure in the form of circuit breakers can be divided into the control of its operating system, power and transmission of three parts.
A vacuum circuit breaker in the structural analysis, functional structure of the base frame by frame module can be divided into the following units:
(1) unit of energy mechanism
→ switch on the unit for complete storage.
Power vacuum circuit breaker switch on no more than two areas: energy storage spring or DC electromagnetic body. As spring operating mechanism can best match the energy transfer, and to various specifications of the circuit breaker breaking current with a generic operator (only the use of different energy storage spring), the optimal cost performance. Therefore, the more advanced circuit breaker abroad and nearly all of spring operating mechanism.
(2) drive mechanism unit
The function of this unit is closing closing → hold (lock) → complete the closing action; sub-gate → (release) → complete the sub-gate action.
Drive mechanism unit consists of four or five bar linkage institutions.
(3) The main drive unit
Main drive unit including the main shaft breaker, insulation putter, adjustable head, even the panels. It is the operating mechanism and vacuum interrupter pole fixed conductive bridge between the power transmission.
(4) Auxiliary Unit
Such as points, closing buttons, points, combined status indicator, auxiliary switch, terminal blocks and circuit breakers necessary chain of devices.
Should be noted that the above is not completely separate functional units, but relatively independent, such as the chain of devices.
2 fault diagnosis of circuit breakers
Vacuum circuit breaker contact opening distance is small, the energy required for operation of small, small impact, organization is simple, so the rare failure. From the failure rate and repair situation, the vacuum circuit breaker is an ideal circuit breaker. This part of the circuit breaker failure compared in Table 1.
Table 1 vacuum circuit breaker failure comparison site
Operator 50
Part 34 of the main circuit
Control section 10
Other 6
Vacuum circuit breaker is faulty, according to its ability to accurately closing, sub-gate and to maintain a reliable closing switch, the OFF position to judge. The main circuit’s fault, from the routine repair and maintenance of circuit breakers found and removed, for example, whether the vacuum interrupter vacuum decreased labor frequency voltage method can be easily identified. Circuit breaker, sub-operation is not normal, and sometimes difficult to find fault, especially the failure to identify a number of integrated more difficult to judge, but as long as the structure of the circuit breaker to find out the principle of functional modules from the start of the investigation, I often see achieving a multiplier effect.
The basic operation of the circuit breaker can be simply described as:
Closing for Storage → → → Closing Closing hold (lock) → Action → minutes to complete closing gate → (release) → complete sub-gate action.
A part of any of these problems will affect the circuit breaker together, sub-operation. Therefore, the analysis point of failure, we should first distinguish the various functional blocks, and then taken step by step process of elimination, one by one investigation.
Fault 1: not on the energy storage
Stored energy is the vacuum circuit breaker is not the fault of the more common, especially in the ratchet, pawl-driven energy storage mechanism, fault probability is higher. Energy storage energy mechanism to complete the action, depending on the energy storage motor, drive mechanism, positioning pieces of the three links. Firmly grasp the three links, it is easy to identify the crux of failure.
Fault 2: No closing action
No action occurred closing the main fault is with the closing solenoid pull, energy storage is in place, locate the relevant pieces of movement is normal.
Fault 3: Air co
A closing movement, but not close together on the gate is called air. In the analysis of such failure, to keep it from closing (locking) to start analysis, then analyze whether the energy storage part of the related.
Fault 4: regardless of gate
This needs to be stressed that the circuit breaker tripping occurs, air time on the analysis of aggregate, etc. prior to repair the main circuit breaker, to fully determine what is the reason for the control and the secondary components such as auxiliary switch, terminal blocks, etc., and then analysis and diagnosis for the circuit breaker.
4 Conclusion
As mechanical and electrical products, vacuum circuit breakers work long live its test is more severe, failure is inevitable, but as long as the circuit breaker control structure principle, fully find out the relationship between functional units, regardless of what the face of kinds of structures in the form of circuit breakers, as long as the investigation according to the procedures step by step, comprehensive analysis to identify trouble spots and is very easy to be excluded.