Causes of excessive current in Radio Tubular Motor :

1. Open circuit of the motor winding
When one of the windings of the motor is open, or one of the parallel branches is open, it will cause the three-phase current to be unbalanced and cause the motor to overheat.

2. Short circuit of the motor winding
When the motor winding has a short-circuit fault, the short-circuit current is much larger than the normal working current, which increases the copper loss of the winding, causing the winding to overheat and even burn.

3. Wrong connection of motor star angle
When the delta connection motor is wrongly connected in a star shape, the motor is still running with a full load, and the current flowing through the stator winding will exceed the rated current, which may even cause the motor to stop by itself. If the stoppage time is a little longer without cutting off the power supply, the winding is not only serious Overheating, it will burn. When a star-connected motor is wrongly connected to form a triangle or a motor with several coil groups stringed into a branch is connected to two branches in parallel, the winding, and the iron core will be overheated, and the winding will be burnt in severe cases.

4. Wrong connection of the motor coil
When a coil, coil group, or one-phase winding is connected reversely, it will cause a serious imbalance of the three-phase current, and overheat the winding.

5. Mechanical failure of the motor
When the motor shaft is bent, the assembly is not good, the bearing is defective, etc., the motor current will increase, copper loss and mechanical friction loss will increase, and the motor will overheat.