4-2 Function Mode Automatic Carrier Frequency Reduction Function •This function automatically reduces carrier frequency according to an increase in output current. •This function is enabled when automatic carrier frequency reduction selection b089 is set to "01". •When output current exceeds 60%, 72%, 84% and 96% of the rated current, the carrier frequency is reduced to 12, 9, 6, and 3 kHz, respectively. When the output current falls below -5% of each level, this function will be reset. 4 Functions Carrier frequency 15.0 kHz 12.0 kHz 9.0 kHz 6.0 kHz 3.0 kHz 0 100 50 Output current (%) 60% 72% 84% 96% •The carrier frequency reduction rate is 2 kHz per second.
•The upper limit of carrier frequency variable with this function conforms to the set value of carrier frequency b083, and the lower limit is 3 kHz. Note: When b083 is 3 kHz or lower, this function is disabled regardless of the b089 setting. 4-70 Parameter No. Function name Data Default setting Unit b089 Automatic carrier reduction 00: Disabled 01: Enabled 00 Carrier frequency reduction starting level (Recovery level) Reduced carrier frequency (kHz) Less than 60% of the rated current 15.0 60% (55%) of the rated current 12.0 72% (67%) of the rated current 9.0 84% (79%) of the rated current 6.0 96% (91%) of the rated current 3.0