The complete insulation burning out on all phases of the three-phase winding is caused by motor overload. Under or overvoltages cause the same type of failure. Picture number 7: The complete insulation burn out on all phases is normally caused by high currents in the stator winding due to locked rotor.
How do you tell if a motor is burned out?
Start by completely disconnecting the spindle motor from all power sources. Check each wire, including T1, T2, T3 and the ground wire. If the reading is infinite, your motor should be fine. If you get a zero reading or any continuity reading, you have either a motor problem or a cable problem.
Can a brushless motor burn out?
Over-revving is a common cause of brushless motors going out. Magnets can be thrown off by too much heat or speed. Generally anything that can cause a brushed motor to destruct can destroy a brushless motor as well. Too much current, too many watts, too much heat…