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For additional assistance, please contact Toshiba Adjustable Speed Drive Marketing Dept. at (800) 872-
2192
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120 Hz Constant Torque Operation of a 60 Hz Motor
The G3’s adjustable volts/hertz relationship and high frequency capability can be utilized in
applications that require a 1:2 constant torque speed range or that have limited space available for
the motor.
The motor will run on 460V power but is wired for 230V. This can be done because the insulation
systems of low voltage motors are good for 600 volts. The drive will put 230V to the motor at
60HZ which the motor winding will need for proper operation. At this time, the motor can deliver
nameplate horsepower and torque. As the inverter continues to increase frequency AND voltage,
motor horsepower increases linearly to double rating at 120 Hz. A graph below shows a voltage
vs. speed curve with torque represented on the same graph by a dotted line.
