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What is the purpose of inserting resistance in the stator circuit during starting?
Explain the reason of inserting a resistor in a motor stator circuit.
Explanation of Solution
A resistor is inserted in a motor stator circuit in series. The voltage drop caused by inserting resistor reduces the voltage across the motor terminals. Reduced voltage results in reduced starting torque and reduced inrush current. Therefore, the resistor is inserted in stator to reduce the starting voltage of a motor and to avoid the winding damages.
Example:
Refer to Figure 26-1 in the textbook where the supply voltage of 480 V is connected across the resistor and the motor which is connected in series. The resistor voltage drop causes the low voltage
Conclusion:
Thus, the reason for inserting a resistor in a motor stator circuit is explained.
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Chapter 26 Solutions
Electric Motor Control
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