The invention and the driving motor are installed in the plating bus nawooteu, and a drive shaft rotated by the drive motor, and the impeller is rotated by the rotation of the drive shaft, the metal pump including a reduction gear that is provided between the drive motor and the drive shaft characterized in that the torque sensor for measuring the torque of the drive shaft, and the current and the torque sensor to measure the operating current of the driving motor, and converts it to a torque, and a rotation sensor for measuring rotation of the drive shaft, wherein torque measuring sensor, the current or torque measuring sensor, received is a measurement result of the rotation detection sensor, when the drive torque rate of the drive shaft for the torque pre-set more than the ratio of the motor and rotating the drive shaft has to generate a reduction gear alarm, If more than the torque rate ratio of the drive shaft for the predetermined torque of the drive motor and the drive shaft is not rotated is characterized in that a control unit for generating a drive shaft bound alarm.
According to the present invention, the torque sensor to the metal pump, current or torque measuring sensor, the reducer installed the rotation measuring sensor, and in accordance with the rotation if the ratio and the drive shaft of the measured values ​​received is a control value measured by said sensor to generate an alarm or alarm drive shaft constrained by informing to the operator the current status of the metal pump, and to accurately predict the maintenance and the replacement time of the metal pump has the effect that can be serviced or replaced, the metal pump on time.