Pwm Carrier Frequency - Toshiba TOSVERT VF-AS1 Instruction Manual

Gradient bias adjustment of analog monitor output
Here is an example of the adjustment of output from 0-20mA → 20-0mA, 4-20mA using the FM terminal. 
The analog output inclination can be adjusted using the parameter  .
5.17

PWM carrier frequency

  : PWM carrier frequency
  : Random mode
  : Carrier frequency control mode selection
• Function
1) The sound tone of acoustic noise can be changed by adjusting 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, this 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
magnetic noise of the motor is increased.
3) The random mode reduces motor magnetic noise by changing the pattern of the reduced carrier frequency.

4) To set the parameter  to  or  has the effect of suppressing voltage surge to the motor. Reduce the
carrier frequency to less than 4kHz if the wiring between the inverter and motor is long (20 to 100m as a
guide).
[Parameter setting]
Title
 PWM carrier frequency
Random mode

Carrier frequency

control mode selection
Note 1: For 37kW to 630kW models, the carrier frequency is between 2.5 and 4.9kHz inclusive.
Note 2: If  is set at 2.0kHz or above, it cannot be decreased below 2.0kHz during operation. Changes made to
decrease  below 2.0kHz take effect when operation is restarted after it is stopped.
 =  ,  = 
(mA)
20
0
0 100%
 =  ,  = 
(mA)
20
large
0
0 100%
Function
 ~  kHz (  ~  kHz) [Note 1]
 :Disabled,  : Enabled
 :Not decrease carrier frequency automatically
 :Decrease carrier frequency automatically
 :Not decrease carrier frequency automatically,
500/575/690V class supported
 :Decrease carrier frequency automatically,
500/575/690V class supported
4: Not decrease carrier frequency automatically,
with sinusoidal filter
5: Decrease carrier frequency automatically, with
sinusoidal filter
 =  ,  = 
(mA)
20
4
0
0
 =  ,  = 
(mA)
20
4
0
0
Adjustment range
E-31
E6581528
100%
small
100%
5
Default setting
According to model
⇒ Refer to page
K-46.

