Three-phase motor winding reverse connection inspection circuit

After the three-phase motor windings are connected reversely or a certain coil is embedded reversely, the direction of the current flowing in the winding becomes reversed, which will cause the three-phase motor to vibrate and produce noise. Moreover, the three-phase current is seriously unbalanced, the motor will overheat, the speed will decrease, and it may even fail. Start, blow the fuse. If one phase winding is connected incorrectly, it usually means that the external leads of the winding are connected incorrectly. At this time, the microampere block of the multimeter can be used to check, as shown in the figure. During operation, connect the three-phase windings according to the head and tail marks, and then turn the rotor of the three-phase motor by hand. If the pointer of the watch does not move, it means that the head and tail of the windings are connected correctly, as shown in Figure (a); if the pointer shakes, indicate a certain If there is a value, it means that there is an error in the head-to-tail connection. You should replace it and try again.