Is it true that full resistance of the Resistor Bank aids in shaft RPMs at normal speed in a Wound Rotor Motor?

Is it true that full resistance of the Resistor Bank aids in shaft RPMs at normal speed in a Wound Rotor Motor?

• A. True
• B. False
• C. It aids only during the startup phase
• D. It doesn't affect performance at any speed

Answer: (B)

In a Wound Rotor Motor, the full resistance of the resistor bank does not contribute positively to shaft RPMs at normal operating speeds. A Wound Rotor Motor operates with varying resistance during different phases of its operation. The purpose of incorporating a resistor bank is primarily during the startup phase, where increased resistance helps limit the starting current and provides better control over the acceleration of the motor. Once the motor reaches its normal operating speed, the resistance of the resistor bank is typically reduced or removed entirely to allow for optimal performance and efficiency. High resistance can actually impede the performance of the motor at this stage, reducing its ability to maintain the desired operational efficiency and torque. Therefore, the statement regarding full resistance aiding shaft RPMs at normal speed is not accurate, making it true that at normal speed, full resistance does not aid and may hinder performance.

In a Wound Rotor Motor, the full resistance of the resistor bank does not contribute positively to shaft RPMs at normal operating speeds. A Wound Rotor Motor operates with varying resistance during different phases of its operation. The purpose of incorporating a resistor bank is primarily during the startup phase, where increased resistance helps limit the starting current and provides better control over the acceleration of the motor.

Once the motor reaches its normal operating speed, the resistance of the resistor bank is typically reduced or removed entirely to allow for optimal performance and efficiency. High resistance can actually impede the performance of the motor at this stage, reducing its ability to maintain the desired operational efficiency and torque. Therefore, the statement regarding full resistance aiding shaft RPMs at normal speed is not accurate, making it true that at normal speed, full resistance does not aid and may hinder performance.