E6581158
F-31
6
6.11
Preset-speed operation frequencies
6.11.1 Preset-speed operation frequency 8 to 15
H
-
H
: Preset-speed operation frequency 8 to 15
See Section 5.14 for details.
6.11.2 Fire-speed control
H
: Preset-speed operation frequency 15 (fire-speed)
•
Function
Fire-speed control is used when operating the motor at the specified frequency in case of an emergency.
If fire-speed control is assigned to the terminal board selection parameter and a fire-speed control signal
is given, the motor will be operated at the frequency specified with
H
(preset-speed operation
frequency 15). (When the terminal board selection parameter is set to 52 or 53).
6.12
PWM carrier frequency
H
: PWM carrier frequency
H
: Random mode
H
: Carrier frequency control mode selection
•
Function
1) The
H
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
H
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 electromagnetic noise by changing the pattern of the reduced carrier
frequency.