Local repair method for grounding fault of stator winding of hydraulic motor

What are the electrical faults that often occur in hydraulic motor stators? Dalan oil pump motor manufacturers tell you that there are two main types: 1. Winding insulation breakdown grounding is more common in high-voltage motors; 2. Inter-turn insulation damage causes inter-turn short-circuit burnout windings, which occur in low-voltage motors. How to find the grounding fault point of the stator winding? The specific method is as follows: 1. Use the smoking method to find the non-metallic grounding of the stator coil. 1 stator coil non-metallic ground fault can be used in this method, but also a simple method. 2 Add a lower voltage between the core and the coil, adjust the voltage with a voltage regulator, and limit the current to within 5A to prevent the core from being burned out. 3 When the current passes through the grounding point, heat is generated at the fault point. Due to the heat, the burning of the insulation may cause white smoke or even sparks. 2. Use the voltage drop method to find metal ground fault points. This method should be carried out with the rotor removed, otherwise there is a risk of high voltage being induced on the rotor windings when AC is applied. The specific steps for finding a metallic ground fault point are as follows: 1 Connect the AC or DC power supply to both ends of the fault phase; 2 Read the corresponding voltage value on the voltmeters V1, V2 and V3; 3 Find the grounding point D proportionally The percentage of the actual length of the lead end A or X; 4 according to the determined, proportionally accurate search for the specific location of the metal grounding point. The partial repair method of the grounding point of the stator winding is as follows: 1. A large current is applied to the coil to be repaired to heat the winding, and the temperature is controlled at about 150 ° C to soften the insulation. 2. Pay attention to safety when using the electric heating method. If the winding has a ground fault, the outer casing may be charged. When the insulation has softened, the power must be cut off before the winding can be started. 3. Cut the end coil to help the rope, take out the spacer, and exit the slot in the slot where the faulty coil is located. 4, the old insulation of the faulty coil, brushed 1410 mica with lacquer, and then continuously wrapped F grade Tongma epoxy powder mica with 9 layers, requiring half-wound wrapping, the upper and lower layers should be staggered, and To bandage the fastening. Finally, another layer of 0.05 mm thick polytetrafluoroethylene film was laminated on the outside. 5. Clean the stator slots and handle the insulation of the remaining coil surfaces, and lower the repaired coil into the slot. 6, wrap the series connector and inline insulation, match the end block, and tie the end of the rope. 7. Perform a withstand voltage test on all windings and measure the DC resistance of the windings. The mutual resistance of the three-phase DC resistance should not exceed 2%. ----- Responsible Editor: Dalan Oil Pump Motor 02- Purchasing Consultant Copyright http:/(Dalan Motor) Reprint, please indicate the source http://news.chinawj.com.cn