1, accident analysis: It is certain that this is an accident caused by a 6KV circuit breaker failure. When the breaker of the coal crusher is turned on in the control room, although the light indicates that the breaker has been turned on, in fact, because the connecting rod falls off or breaks, the two phases of the breaker are not disengaged, which leads to the two-phase operation of the coal crusher, the motor torque drops, the speed drops (by inertia operation), the current increases abnormally, and the coil is seriously heated and smoked after a few minutes. Due to the failure of the transmission part of the circuit breaker, of course, panic button cannot be used to break the brake. Finally, after a long time, the motor of the coal crusher caught fire and had to stop for treatment.

Precautionary measures: The transmission parts of 6KV circuit breakers frequently fail, especially for some frequently operated equipment, the inspection and maintenance should be strengthened. Operators should be calm, analyze correctly and pay attention to personal safety when encountering such abnormal situations.