Siemens Washing Machine Frequently Suddenly Powers Off During Spin Cycle
Beijing Siemens Washing Machine Repair Technical Information.
For computerized washing machines, the working state of certain components is affected by load and temperature. Sometimes during operation, the washing machine suddenly stops turning, the indicator light goes out, but after disconnecting the power to the washing machine, it can restart and run again after some time. This type of fault often occurs in washing machines with a three-terminal integrated voltage regulator in their DC power supply circuit, and it usually happens during the spin cycle. The reason for the fault is that the quality of a certain device in the DC power supply circuit is poor, causing changes in its operational characteristics when temperature and load change, leading to instability in the circuit's operating state. Commonly faulty devices include the power transformer and filter capacitor.
As the temperature rises gradually during operation due to poor insulation of the transformer, the rise in temperature further degrades the insulation performance, causing the output voltage to drop. When the microprocessor and other loads consume a large amount of electricity, the leakage current of the transformer increases further, causing the voltage delivered to the regulator to decrease further. When the washing machine enters the spin cycle, the microprocessor and other components consume the maximum power, causing the transformer's output voltage to drop further. The three-terminal integrated voltage regulator enters an overheat protection state due to the excessively low input voltage, causing the washing machine to suddenly power off, the indicator light to go out, and the operation to stop. After disconnecting the power to the washing machine for some time, the three-terminal integrated voltage regulator returns to normal, allowing the washing machine to restart, the microprocessor to reset, and the washing machine to start running again from the beginning according to the program.
Poor insulation of the filter capacitor, resulting in high leakage current, can also cause the three-terminal integrated voltage regulator to enter a self-protection state. When the washing machine frequently powers off suddenly during the spin cycle, you can check the power transformer and filter capacitor. If you find any component with a higher temperature, it indicates a faulty element. Simply replacing the faulty component will resolve the issue.