Pwm Carrier Frequency And Long Wiring Mode (Pr. 70 , Pr. 72 ) - Mitsubishi Electric FR-S500E Instruction Manual

2.10.2 PWM carrier frequency and long wiring mode (Pr. 70
, Pr. 72
You can change the motor sound.
Parameter
70 Soft-PWM setting
72 PWM frequency selection
<Setting>
By parameter setting, you can set whether to exercise Soft-PWM control that
changes the motor tone or select with or without long wiring mode.
Soft-PWM control is a control system that changes the motor noise from a metallic tone into an
unoffending complex tone.
Surge voltage is suppressed regardless of wiring length in the long wiring mode. (When
operating the 400V motor with wiring length of 40m or longer, select the long wiring mode.)
Pr.70
Setting
Soft-PWM
0 Invalid
1 (When Pr. 72 setting
= any of "0" to "5")
10 Invalid
11
CAUTION
1.The output voltage at the rated frequency drops by a maximum of 5V.
2.For the 400V class, use an insulation-enhanced motor.
Refer to page 19 for an inverter-driven 400V class motor.
Pr.72 Setting
PWM carrier frequency can be changed.
0 to 15 The setting displayed is in [kHz].
Note that 0 indicates 0.7kHz and 15 indicates 14.5kHz.
REMARKS
An increased PWM frequency will decrease the motor sound but increase noise and leakage
currents. Therefore, perform the reduction techniques. (Refer to page 16.)
Metallic sound may be generated from the motor at sudden deceleration but it is not a fault.
Refer to
)
Name
Long wiring mode
Valid
Valid
Description
(page 67).
Operation selection function parameters
Factory Setting
Setting Range
1 0, 1, 10, 11 Setting is enabled when
1 0 to 15
Description
Invalid
Invalid
When Pr. 72 "PWM frequency
Valid
selection" = 1 or more, the PWM
carrier frequency is constant at
1kHz. (When "0" is set, the PWM
Valid carrier frequency is constant at
0.7kHz.)
101
Remarks
Pr. 30 = "1"
Remarks
2