Performance requirements of operating mechanism

During the operation of MCCB, 80% of the faults often occur in the operating mechanism. When the fault occurs, it is often in the place that is not easy to be detected by people, and the operating mechanism is no exception. The operating mechanism is in static operation all the year round, so it is difficult to monitor its use status to check the fault. Especially for the equipment in the outdoor environment, it is affected by humidity, temperature, corrosion, etc., which are more likely to cause the failure of the operating mechanism, so the maintenance of the operating mechanism is very important Mechanism optimization, the use of new materials, the improvement of new technology, and the improvement of machining accuracy are long-term tasks to be solved.

In order to make MCCB have good mechanical and electrical performance, the operating mechanism as its core component should have the following capabilities.

1) It has stable opening and closing ability to avoid the phenomenon that the moving and static contacts are not closed in place when closing;

2) When the dynamic and static contacts are closed, the stability of the dynamic and static contacts should be maintained, that is, there should be appropriate final pressure;

3) Good consistency of opening and closing, avoid frequent mechanical operation, failure;

4) The opening and closing time is short, which is conducive to improving the breaking capacity of the product and breaking the fault current in time;

5) The bouncing of opening and closing should be small to avoid the arcing caused by bouncing and increase the contact resistance;

6) The value of overtravel is large, which can avoid the unstable power on of the moving and static contacts after burning and avoid the danger;

7) High mechanical life is a key index of circuit breaker product stability;

8.Reduce the fatigue fracture caused by repeatedly switching on and off of the operating mechanism.