Views:3 Author:Site Editor Publish Time: 2019-08-16 Origin:Site
How can an electric hoist not start and run?
Electric hoists are widely used in enterprises due to their various forms, light and flexible, simple operation and convenient maintenance. This article will analyze the failure of the electric hoist electric hoist to start and operate.
First, check if the power fuse is blown. If one phase is broken, the motor is single-phase starting at this time, the starting torque is zero, then the motor cannot rotate, and enough fuse should be replaced.
Second, it may be that the voltage of the grid is too low. Because the starting torque is proportional to the square of the voltage, the acceleration torque cannot overcome the load torque, so the operating speed cannot be reached. In this case, the voltage of the power grid should be properly increased.
Again, there may be a short circuit, ground or open circuit between the phases of the stator windings. If the winding grounding occurs at the grounding plate of the lead-out, the junction box should be opened for inspection. If there is an open circuit, not only the motor should be inspected, but also the wiring of the control device should be checked first. If the contact of the AC contactor is poor, the line cannot be connected. At this time, apply the sandpaper to the contact of the contactor. When smoothing, check the connection and disconnection of the core, whether there is any jamming, and replace the new suitable contactor if necessary.
Finally, there may be a load that is too large or the transmission machinery is faulty. The power of the motor matched by the electric hoist is reasonable. When the heavy object is lifted, the overload condition cannot occur. If the electric hoist cannot be rotated, the load should be removed first. At this time, if the motor can be started normally, it indicates that the transmission mechanism such as the reduction gearbox has a fault, and the driven mechanism should be checked to clear the fault.