Beijing Ronshuda washing machine after-sales service telephone on August 23, 2011.
Ronshuda Washing Machine, Electric Motor Housing Electric Repair Experience
When the motor is powered on, touching the end cover of the motor gives an electric shock feeling. When repairing Ronshuda washing machines, use a voltage tester to detect electricity. The electrification of the motor end cover is generally caused by reduced insulation performance of the motor. Use a megohmmeter (or multimeter) to measure the insulation resistance of the main and auxiliary windings of the motor to ground (i.e., the motor end cover). During testing, connect the three leads of the motor together with one end of the megohmmeter, and connect the motor end cover to the other end of the megohmmeter. The normal value of the motor resistance is above 50MΩ (the standard specifies 2MΩ). If the value is several megaohms or lower, it is considered abnormal, which indicates a decrease in insulation performance; if the meter needle wavers, it means that the insulation has been basically broken down, but there is still an insulating layer with a very small resistance; and if the resistance approaches zero, it indicates that the winding lead of the motor has short-circuited with the end cover. When touching the motor end cover gives an electric shock feeling, the insulation resistance of the motor has dropped below 0.1MΩ. Common reasons for the drop in insulation resistance are motor dampness or excessive dust accumulation. For the former, the motor can be removed and placed in the sun to dry or use a hairdryer to drive away moisture; for excessive dust accumulation, open the motor and clean it. If it is determined that the motor insulation has broken down, the winding needs to be repaired, rewound, or the motor replaced. If it is determined that the motor has a ground fault, check first whether the motor lead is worn, then see if any debris has fallen into the motor or if the assembly state of the motor is normal. Open the motor to look for grounding points on the surface of the winding. If it is determined that the grounding point is between the winding and the stator core, the winding should be rewound.