4-2 Function Mode „ Constant Torque Characteristics (VC) Output voltage is proportional to output frequency. While proportional from 0 Hz to base frequency, the output voltage is constant from base to maximum frequencies. Output voltage (100%) Output frequency (Hz) 0 Base frequency Max. frequency „ Special Reduced Torque Characteristics (Special VP) 4 Suitable for a fan or pump that requires torque in a low speed range. These have VC characteristics only for low deceleration in reduced torque characteristics. Functions Output voltage (100%) VC Output frequency (Hz) 0 10% of base frequency Base frequency Max. frequency Period a:
Provides constant torque characteristics within a range from 0 Hz to 10% of the base frequency. (Example) If the base frequency is 60 Hz, the Inverter provides constant torque characteristics within a range from 0 to 6 Hz. Period b: Provides reduced torque characteristics within a range from 10% to 100% of the base frequency. The Inverter outputs voltage based on a curve of the 1.7th power of the frequency. Period c: Provides constant voltage characteristics within a range from the base frequency to the maximum frequency. a b c „ Free V/f Setting •You can set desired V/f characteristics by setting 7 points of voltage and frequency.
(b100 to b113) •The free V/f frequencies should always be 1 ≤ 2 ≤ 3 ≤ 4 ≤ 5 ≤ 6 ≤ 7. All the default settings are 0 Hz. You must set Free V/f setting 7 first. (Operation is disabled by factory default.) 4-22 VP(f 1 .7 )