How to check the grounding fault of the armature winding of the DC motor?

The armature winding grounding fault, is generally a notch or commutator internal breakdown breakdown, and the winding end of bracket breakdown. Commonly used inspection methods are as follows:

1 measurement of the pressure between the chip. The voltage DC power supply is connected to the reversing plate and the shaft, and the pressure drop between the two pieces is measured, and the pressure drop of the reverse voltage drop between the adjacent ground is opposite to that of the power source.

2 measuring the pressure drop between the reverse plate and the shaft. The low-voltage DC power supply received apart in a distance of two commutator on, measuring commutator and axial pressure drop, if somewhere in the pressure drop for zero or very little, it is to take place.

3 test light inspection. 220V small power AC test lamp is connected to the reversing plate and the shaft, and the location of the ground is judged according to the spark, smoke and noise observed in the test.