The electric chain hoist is used for a long time or is improperly operated, and various failures will occur. We have sorted out the following common failures, causes and troubleshooting methods for you.
The sliding distance of stopping when braking exceeds the specified requirements
When the electric chain hoist is used for a long time, the brake ring wears too much, which reduces the pressure of the brake spring and the braking force. The solution is to adjust the brake bolt or replace the brake ring.
The heavy object rises to mid-air and cannot be restarted after stopping
First check whether the system voltage is too low or whether the fluctuation is too large. If this is the case, only wait for the voltage to return to normal before starting; on the other hand, pay attention to the lack of phase in the operation of the three-phase motor, and it cannot start after stopping. In this case, check Number of power phases.
Can’t stop or reach the limit position and still don’t stop
This kind of situation is generally the contact welding of the contactor. When the stop switch is pressed, the contact of the contactor cannot be disconnected, the motor is energized and the hoist does not stop; if the limiter fails, the hoist does not stop. parking. In this case, immediately cut off the power supply and force the hoist to stop. After parking, check the contactor or limiter. If it is seriously damaged and cannot be repaired, it must be replaced.
The motor cannot start if there is no fault in the circuit
During winter construction, especially after snow, the motor still cannot start if there is no fault in the circuit. The reason is that the brake ring freezes to death. If the motor is forcibly turned on at this time, it will easily burn the motor. The solution is to open the motor cover and use a crowbar to pry the motor so that it can rotate freely.
The lifting chain or wire rope can’t go up or down.
The reason is that the stroke limiter is damaged, and the stroke limiter needs to be replaced.
The temperature rise of the electric hoist motor is too high
First of all, check whether the electric chain hoist is overloaded. Overloading will cause the motor to heat up. Long-term overloading will burn the motor. If the motor is not overloaded, it still heats up. Check whether the motor bearing is damaged. Check whether the motor is working according to the specified working system. This is also caused. One of the reasons for the motor heating is to strictly follow the motor working system when using it. When the motor is running, the brake gap is too small and not completely disengaged, resulting in a lot of friction. The friction heat is also equivalent to an additional load, which reduces the motor speed, increases the current and generates heat. At this time, stop working and restart. Adjust the brake gap.

Through the analysis of common failures and treatments of electric chain hoists, the maintenance personnel of electric chain hoists can know where to start inspections when dealing with failures and improve the efficiency of maintenance.

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