Motor Control Resistors 

 

DC Series Wound Motor Resistor

The resistor limits torque by limiting current flow to the motor and is used for starting and stopping the motor.

 Initial information needed by us:

• Application

• Horsepower

• Line voltage

• Full load amps

• Starting torque

• Number of speeds

• Duty rating i.e. ON time and OFF time cycle for each section of resistor etc.

 

 

AC Squirrel Cage Induction Motor Resistor

The resistor acts as a voltage divider for soft starting of the motor.

Initial information needed by us

• Application

• Horsepower

• Line voltage

• Full load amps

• Resistance value and current rating.

• Duty cycle rating i.e. ON time and OFF time cycle for each section of resistor etc.

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AC Wound Rotor Induction Motor Resistor (Slip Ring Motor)

The resistor is connected in series with the slip ring winding to provide “soft starting” as resistance is removed in steps.

Initial information needed by us:

• Application

• Horsepower

• Secondary volts

• Secondary amps

• Starting torque

• Number of resistance sections

• Duty cycle rating i.e. ON time and OFF time cycle for each section of resistor etc.

 

 

 

 

 

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Star Delta / Wye-Delta Starting Resistor

Wye-delta is a reduced-inrush starting method in which 3 phase motor stator coils are initially connected in a wye configuration and switched to delta as the motor’s speed increases. The resistor works as a reduced voltage starting resistor by starting a motor at 58% reduced voltage.

Initial information needed by us:

• Application

• Horsepower

• Line voltage

• Full load amps

• Resistance Value

• Duty cycle rating i.e. ON time and OFF time cycle for each section of resistor etc.

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For other applications, such as railways where resistor is used for field diverter / tap changer / arno converter, Please contact is with details.