A highspeed roatating cutter is assembled at the inlet hole of the pump,make it easy to cut off long firm sundries cintained in the sewage,so as to avoid the impeller is blocked by the entanglement. It is suitable for draining sewage in sanitation,factory,mine and familly.The float switch can automatically control on and off with the change of the liquid level. The protector in the motor can automatically cut off the power when it overheated or overcurrented,thus guarantee the security and reliability of pump's run even in the atrocious environment.