55
4. Parameter description
Parameter
Note: In this curve the motor vibration can be reduced substantially during acceleration/deceleration, and thus the
life span of belts and gears is expanded.
4.15 Regenerative Brake (P.30, P.70)
P.30 “Regenerative brake function selection”
P.70 “Special regenerative brake duty”
● At the moment when the output frequency switches from high to low, due to the load inertia, the
motor speed will be higher than the output frequency of the inverter, and thus the generator effect
is formed. It results in high voltage between the main-circuit terminals P and N, which will
damage the inverter. Therefore, a proper brake resistor shall be mounted between the terminals P
and PR to dissipate the fed-back energy.
● There’s a built-in transistor (called as brake transistor) in the inverter. The conducting time ratio of
the transistor is called as ‘regenerative brake duty’. The Higher the regenerative brake duty is, the
more energy the brake resistor consumes, and the stronger the brake capability is.
Parameter Factory setting
Setting range
Remarks
30
0
0~1
0
If regenerative brake duty is 3%
fixedly, the
value of parameter 70 is failure.
1
The regenerative brake duty is the value witch
parameter 70 setting.
70
0
0~30%
---
Note: 1. In occasions where frequent start/stop occurs, a high capacity brake resistor is required.
2. Refer to Section 2-7 for brake resistor selection.
4.16 Soft-PWM (P.31)
P.31 “Soft-PWM selection”
●
Soft-PWM
is a method witch control the motor noise become melody.
● Motor noise modulation control is when the inverter varied its carrier frequency from time to time
during operation. The metal noise that generates by motor is not a single frequency. This function
selection is to improve the high peak single frequency noise.
●
Soft-PWM
is valid in V/F curve. It means P.300 must be set to 0.
Parameter
Factory setting
Setting range
Remarks
31
0
0
No Soft-PWM selection
1
When P.72<“5”
，
with Soft-PWM selection
