E6582233
F-22
6
6.12 PWM carrier frequency
: PWM carrier frequency
: Random mode
: Carrier frequency control mode selection
Function
1) The
parameter allows the tone of the magnetic noise from the motor to be changed by
switching the PWM carrier frequency. This parameter is also effective in preventing the motor from
resonating with its load machine or its fan cover.
2) In addition, the
parameter reduces the electromagnetic noise generated by the inverter.
Reduce the carrier frequency to reduce electromagnetic noise. Note: Although the electromagnetic
noise level is reduced, the acoustic noise of the motor is increased.
3) The random mode reduces motor electromagnetic noise by changing the pattern of the reduced carrier
frequency.
[Parameter setting]
Title
Function
Adjustment range
Default setting
PWM carrier frequency
2-12 (kHz)
4
Random mode
0: Disabled, 1: Automatic setting
0
Carrier frequency control mode
selection
0: Carrier frequency without reduction
1: Carrier frequency with automatic reduction
2: Carrier frequency not reduced automatically
Support for 400V models
3: Carrier frequency reduced automatically
Support for 400V models
3
Note 1: Some models need reduced current ratings, depending on the PWM carrier frequency
settings.
Refer to the table on the following page.
Note 2: When the PWM carrier frequency is set high, selecting “Carrier frequency not reduced automatically”
causes the inverter to be tripped more easily than selecting “Carrier frequency reduced automatically.”
Note 3: When
f316
=
2
,
3
, to avoid motor unstable PWM carrier frequency is limited by 4kHz internally and if
is set more than 4kHz,
is displayed.