What function does a thermistor serve in a 3-phase winding?

In a 3-phase winding, a thermistor primarily serves the function of breaking the control circuit when overheating is detected. This is crucial for preventing damage to the motor as overheating can lead to insulation failure, reduced efficiency, and potentially catastrophic failure of the winding.

The thermistor is sensitive to temperature changes, and as temperature increases, the resistance of the thermistor decreases. When the temperature exceeds a predetermined threshold, the change in resistance can trigger a control mechanism that interrupts the power supply to the motor, effectively preventing further heating and ensuring the safety of the system.

This preventive measure is vital in maintaining the longevity and reliability of electrical components in a motor system, especially under varying operational conditions that could lead to excessive heat generation.