When using the electric chain hoist for lifting, the rated load of the electric chain hoist and the weight of the goods should be clarified. When the weight of the hoist is unknown, it is forbidden to lift. In addition, when the weight of the heavy Object is clarified, the equipment of more than 25% of the weight should be Selected ( Prevent full load and reduce the pressure of electric chain hoist). If the lifting force of the electric chain hoist is insufficient, the following reasons should be considered.

Check whether the power fuse of the device is blown. If one phase is broken, the electric hoist motor will start in a single phase, the starting torque is zero, and the motor will not rotate, and enough fuses should be Replaced.
The grid voltage is too low. The starting torque is proportional to the square of the voltage. The acceleration torque cannot overcome the load torque and cannot reach the operating speed. The grid voltage should be increased.
The stator winding is short-circuited, grounded or open circuited between phases. When the winding is grounded, the junction box should be opened for inspection; in addition to checking the motor when the circuit is broken, the control equipment should also be checked for correct wiring, and the contactor should be Replaced if necessary.
The load is too large or the transmission machinery is faulty. Generally, it is reasonable to match the motor power of the electric chain hoist. If the hoist cannot be overloaded, if the electric hoist cannot be rotated, first remove the load. If the motor can start normally, it means that the gearbox and other transmission mechanisms are faulty and should be checked. Mechanism to clear the fault.
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