4-2 Function Mode * To switch to the 2nd control, allocate 08 (SET) to the multi-function input and then turn it on. 4 „ Control Method (V/f Characteristics) Functions 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 regardless of the frequency. Output voltage (100%) Output frequency (Hz) 0 Base frequency (A003/A203) Max. frequency (A004/A204) Special Reduced Torque Characteristics (Special VP) •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. Output voltage (100%) VC Output frequency (Hz) 10% of base frequency 0 Base frequency (A003/A203) Max. frequency (A004/A204) a b c Period a: Provides constant torque characteristics (VC) 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 within a range from the base frequency to the maximum frequency. 4-12 Parameter No. Function name Data Default setting Unit A044 V/f characteristics selection 00: Constant torque characteristics (VC) 01: Special reduced torque characteristics (Special VP) 02: Intelligent sensorless vector control (iSLV) 00 A244 * 2nd V/f characteristics selection A045 Output voltage gain 20. to 100. 100. % A245 *2nd output voltage gain Related functions A046, A246, A047, A247, A082, H003, H203, H004, H204 VP (1.7th power of VP)