Most electric hoists use three-phase electricity. Recently, many customers have called and found that electric hoists may experience current imbalance and other faults during use. Below, Shanghai Yiying summarizes the methods for handling current imbalance faults:

    1. Motor winding inter turn short circuit fault. You can observe whether there are areas where the coil is burnt or discolored due to high temperature at the end of the winding, or smell insulation burning. If there is an inter turn short circuit in the coil, the reading of the ammeter connected in series to the coil circuit of the short circuit detector will significantly increase;

    2. The open circuit fault of the winding can be checked by measuring the three-phase resistance with a multimeter or bridge meter. The maximum difference in the three-phase resistance of the motor winding should not exceed 3% of the average value of the three-phase resistance;

    3. To check for reverse connection faults in some coils of the stator winding, a low-voltage DC voltage can be applied to a certain phase winding, and the polarity of each slot along the iron core surface can be checked using a compass.

    4. For faults with unequal turns of three-phase windings, the first and last ends of the phase can be connected in series and powered on, and the voltmeter can be used to measure the voltage drop section by section.

    Measure whether the voltage of each phase is equal, then measure whether the voltage of each pole group in the abnormal phase is equal, and finally measure whether the voltage of each coil in the abnormal pole group is equal, to find the coil with the wrong number of turns.