The work of a permanent magnet China Speed Control AC Motors is closely related to electricity, but if there is a fault in the circuit, not only it itself will be affected, but we can't grasp its repair method, so it is necessary for us to learn how to find the fault and solve it.If the armature winding is severely short-circuited, it will burn out. If only individual coils are short-circuited, the motor can still run, but the surface spark of the commutator becomes larger, and the armature winding heats up seriously. If it is not found and eliminated in time, it will eventually cause the motor to burn.Therefore, when the armature winding has a short-circuit fault, it must be eliminated in time. Armature winding short-circuit faults mainly occur in the inter-turn short-circuit of the same-slot winding components and the short-circuit between the upper and lower winding components. Common methods for finding short circuits include:1. The short-circuit tester method is the same as the previous method for finding the short-circuit between the turns of the stator winding of the three-phase asynchronous motor. After the short-circuit tester is connected to the AC power supply, it is placed on a slot of the armature core, and the broken saw blade is placed in the other slots. The upper part of the opening moves in parallel, and when a relatively large vibration occurs, the winding component in the slot has a short circuit fault.2. Apply 6.3V AC voltage (DC voltage can also be used) to two commutation slices separated by K\/2 or K\/4, and use two meter pens of a millivoltmeter to sequentially contact the two adjacent commutation slices of the commutator , Detect the inter-chip voltage of the commutator. During the detection process, if the reading of the millivoltmeter suddenly becomes smaller, for example, the test reading between two commutator segments suddenly becomes smaller, it means that the armature winding component connected to the two commutator segments has a short circuit between turns. If the voltage between the commutation segments is equal during the detection process, it means that there is no short-circuit fault.