3. 4 Others precautions
(1) Set the PWM frequency (Pr.72) low by the parameter setting.
Some models allow their PWM frequencies to be set lower. Doing this can reduces
the interference generated from the inverter, but increases the acoustic noise
generated from the motor.
(2) Increase the input filter time constant (Pr.74) of the inverter by the parameter setting.
Some models allow their filter time constant settings, which are used for the
frequency setting signal input, to be changed. The frequency setting signals are
given by external voltage or current input. Set this filter time constant higher if the
operation is unstable because of the interference. Note that setting this value higher
will make the inverter response slow.
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