3. Main technical parameters
3.1 structural features
3.1.1 the circuit breaker adopts integrated and modular design, with simple and reasonable overall structure. It is set up and down, the arc extinguishing chamber is above, and the interlocking and operating parts are below. Special spring pneumatic operating mechanism is used, without adjustment, and the action is stable and reliable.
3.1.2 the vacuum arc extinguishing chamber of the three-phase conductive circuit of the circuit breaker is arranged in a closed insulating cylinder, which is made of materials with reliable electromechanical performance and mature vacuum pouring process. In this way, not only the phase to phase insulation performance is significantly improved, but also each phase circuit is not affected by the harsh external environment, dust and foreign matters can be prevented from entering the main circuit, and the overall size of the circuit breaker is reduced.
3.1.3 the circuit breaker adopts wl-35855x vacuum interrupter produced by Cutler hammer company of the United States or the domestic design coil type vacuum interrupter with longitudinal strong magnetic field structure. It adopts ceramic shell and copper wall chromium contact material. It has small overall size, high insulation level, strong arc extinguishing ability, long electrical life and excellent performance of breaking and closing short-circuit current.
3.2 mechanical action principle
Figure 2 shows the internal structure of the circuit breaker
The circuit breaker is mainly composed of conductive circuit, arc extinguishing system, insulation system and operating system. The dynamic conducting rod of the arc extinguishing chamber is connected with the operating mechanism through an insulating pull rod and a transmission connecting rod.
3.2.1 closing operation: the operating mechanism 9 stores energy to the closing spring by the motor. After the closing electromagnet acts, the closing spring pushes the crank arm 7 to rotate counterclockwise through the cam and connecting rod 8, and the crank arm drives the connecting rod mechanism 6 and screw 5 to move upward to complete the closing operation. At the same time, energy is stored for the opening spring and contact pressure spring. Keep the contact of the arc extinguishing chamber under a certain pressure and prepare for the opening operation.
3.2.2 opening operation: the opening electromagnet acts after being energized, the closing switch in the operating mechanism trips, and the moving guide rod of the arc extinguishing chamber moves downward driven by the opening spring to complete the opening operation of the vacuum chamber.
3.2.3 manual energy storage operation: insert the manual energy storage operation handle into the jack of the operating mechanism, then swing left and right (about 60), and use the one-way bearing to complete the energy storage of the closing spring. After energy storage, you can manually press the closing and opening buttons to realize the closing and opening operation.
Post time: Aug-31-2021