Free V/F Setting - Omron SYSDRIVE MX2 SERIES User Manual

5-5 Settings Relating to Control Method
Reduced Torque Characteristics (VP 1.7th power)
Suitable for a fan or pump that does not require large torque in a low speed range.
It will provide high efficiency, reduce noise and vibration, owing to reduced output voltage in a
low speed range.
V/f characteristics are shown below.
Output voltage
(100 %)
Period (a): Provides constant torque characteristics within a range from 0 Hz to 10% of the
Period (b): Provides reduced torque characteristics within a range from 10% of the base
5
Period (c): Provides constant voltage characteristics within a range from the base frequency

Free V/f Setting

Under the free V/f setting function, desired V/f characteristics can be set by setting seven
points of voltage and frequency.(b100 to b113)
The set frequency should always be 1 ≤ 2 ≤ 3 ≤ 4 ≤ 5 ≤ 6 ≤ 7.
All default data is 0 Hz, so set free V/f frequency 7 first. (Operation is disabled by factory default.)
If the free V/f setting is enabled, the functions of Torque Boost Selection (A041/A241), Base
Frequency (A003/A203), and Maximum Frequency (A004/A204) are disabled. (Free V/f
frequency 7 is handled as the maximum frequency.)
Parameter
b112
b110
b108
b106
b104
b102
b100
5-47
VP (f
VC
0
10 % of base Base frequency
frequency
(a) (b)
base frequency.
Example) If the base frequency is 60 Hz, the Inverter provides constant torque
characteristics within a range from 0 to 6 Hz.
frequency to the base frequency.
The Inverter outputs voltage based on a curve of the 1.7th power of the frequency.
to the maximum frequency.
Function name
No.
Free V/f Frequency 7 (f7)
Free V/f Frequency 6 (f6)
Free V/f Frequency 5 (f5)
Free V/f Frequency 4 (f4)
Free V/f Frequency 3 (f3)
Free V/f Frequency 2 (f2)
Free V/f Frequency 1 (f1) 0. to Free V/f frequency 2
1.7
)
Output frequency (Hz)
Maximum frequency
(c)
Data
Free V/f frequencies 6 to
400. (1000.)
Free V/f frequency 5 to
free V/f frequency 7
Free V/f frequency 4 to
free V/f frequency 6
Free V/f frequency 3 to
free V/f frequency 5
Free V/f frequency 2 to
free V/f frequency 4
Free V/f frequency 1 to
free V/f frequency 3
SYSDRIVE MX2 Series USER'S MANUAL (3G3MX2-Axxxx)
Default
Unit Description
setting
0. Hz
0.
0.
Set
frequencies
0. for each break
point.
0.
0.
0.