circuit breaker operating mechanism, because whether the circuit breaker can operate effectively and reliably depends to a large extent on the performance and quality of the operating mechanism, so according to the different circuit breakers, the empty operating mechanism should meet the required properties and reliability. ,mainly in the following points:

should have sufficient closing function

In actual work, the energy of the operating mechanism will not remain at the rated value, but will change within a certain range. According to the requirements of power-related regulations, the lower limit is 8085% of the rated value, and the upper limit is 119% of the rated value. That is to say, when the operating mechanism is at the lower limit, it can break the short-circuit current, and when the upper limit is °, the relevant components should not be damaged due to excessive operating force. Moreover, when the power grid is short-circuited, the short-circuit current in the circuit can reach 40kA, or even greater, and the electric power that the circuit breaker can withstand can reach more than several thousand Newtons. The operating mechanism must overcome such a huge electric power before closing. breaker.

Should have the ability to maintain inter-combination

In order to reduce the overall size of the circuit breaker and reduce energy consumption, the switch coil is designed as a short-time working system, which only allows the closing current in a very short time. If the power-on time is too long, the closing coil will be burned. This requires the operating mechanism to maintain the circuit breaker in the switch position after the closing coil loses power

Have a relatively short switching time

The opening of the circuit breaker means that the circuit must be interrupted, and an arc must occur. When a short-circuit fault occurs, the short-circuit current is much larger than the normal load current. When the system is short-circuited, the system circuit behaves as an inductive circuit, so when the AC current crosses zero, the dynamic and static contacts of the circuit breaker are separated at the moment when the dynamic and static contacts are separated. The voltage cannot be abruptly changed, and a transient recovery voltage will appear. In order to achieve the purpose of breaking the circuit, the operating mechanism must provide a certain speed of opening, especially the speed of just opening (the speed at which the moving contacts are just separated during the opening process of the switch)

With anti-jump device

In order to avoid the phenomenon of continuous multiple splits after the circuit breaker is closed, mechanical or electrical methods should be used so that the circuit breaker cannot be arbitrarily split or split after the circuit breaker is opened, so as to reduce unnecessary actions.

There should be linkage device

There is a linkage device in the operating mechanism to ensure the reliability of the circuit breaker, so that when the circuit breaker is in a state, it will not be affected by the misoperation of the operating mechanism. Generally, the operating mechanism should have the opening position interlock, low air pressure and High air pressure interlock, position interlock in spring mechanism, etc.