Toshiba VF-nC1 - Manual (Page 76)

E6581090
F-12
6
6.7 Jump frequency – Jumping resonant frequencies
H : Jump frequency (Hz)
H : Jump width (Hz)
• Function
Resonance due to the natural frequency of the mechanical system operated can be avoided by
jumping the resonant frequency during operation. During jumping, hysteresis characteristics
with respect to the resonant frequency are given to the motor.
Jump width (H) Jump frequency (H)
Output frequency [Hz]
Frequency setting signal 0
[Parameter setting]
Title Function Adjustment range Setting
H Jump frequency (Hz) NN～WN (Hz) 0.0
H Jump width (Hz) 0.0～ 30.0 (Hz) 0.0
☆ Do not set jump frequencies that overlap each other.
☆ During acceleration or deceleration, the jumping function is disabled for the operation frequency.
6.8 Preset speed operation frequencies 8 to 15
H ～ H : Preset speed operation frequencies 8 to 15 (Hz)
See Section 5.11 for details.
6.9 PWM carrier frequency
H : PWM carrier frequency
• Function
1) This parameter is used for changing the carrier frequency in order to change the tone of the
magnetic noise produced by the motor. This parameter is also effective in preventing the
motor from resonating with its load machine or fan cover.
2) In addition, this parameter is used to reduce the electromagnetic noise produced by the
inverter. To reduce the electromagnetic noise, decrease the carrier frequency.
Note: This reduces the electromagnetic noise but increases the magnetic noise from the motor.
3) If the PWM carrier frequency is set above 4kHz, it may fall automatically during acceleration
or under certain circumstances where an overcurrent flows.
[Parameter setting]
Title Function Adjustment range Setting
H PWM carrier frequency
0:2kHz
1:2kHz(random control)
2:4kHz
3:4kHz(random control)
4:8kHz (automatic reduction mode) *1
5:12kHz(automatic reduction mode) *1
6:16kHz(automatic reduction mode) *1
5
*1 Cartain models require to reduce the rated load current according to carrier frequency setting
as following table.