Omron SYSDRIVE MX2 SERIES, User Manual

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5 Basic Settings
5 - 10 Multi-function Compact Inverter 3G3MX2-V1 User’s Manual (I585-E1)
This setting is suitable for fan, pump, and other applications that do not require large torque at low
speeds.
It provides high efficiency, reduced noise, and vibration, because the output voltage is reduced in the
low speed range.
In the low speed range at 10% of the base frequency or lower, the setting provides constant torque
characteristics (VC) to secure a sufficient starting torque.
• The free V/f function is suitable for the applications listed below.
The output voltage of the inverter can be adjusted according to your application.
• With the free V/f function, you can configure V/f characteristics by setting the voltage and frequency
values at seven points. For any unused points, set the corresponding Free V/f Frequency 1 to 7 to 0
(Disabled).
• The set values of the Free V/f Frequency 1 to 7 must satisfy the following relationship:
1
≤
2
≤
3
≤
4
≤
5
≤
6
≤
7.
All of the default data are set to 0 Hz. Start by setting the Free V/f Frequency 7 (b112) and Free V/f
Voltage 7 (b113).
Reduced Torque Characteristics (VP 1.7th Power (VC at low speed))
Range (a): Constant torque characteristics are provided within the range from 0 Hz to 10% of the
base frequency.
(Example) If the base frequency is 60 Hz, the setting provides constant torque charac-
teristics within the range from 0 to 6 Hz.
Range (b): Reduced torque characteristics are provided within the range from 10% to 100% of the
base frequency.
The inverter outputs voltage based on a curve of the 1.7th power of the frequency.
Range (c): A constant voltage is output within the range from the base frequency to the maximum
frequency.
Free V/f Function
Application Adjustment method
Motor integrated with a brake (that uses
a shared power supply for the motor and
the brake)
If the motor and the brake share the same power supply, a large volt-
age is required at low frequencies to release the brake.
The release timing of the brake can be adjusted by setting the fre-
quency at which you want to release the brake and adjusting the volt-
age at that frequency.
Applications subject to significant load
variation at different motor speeds
When the load value changes significantly depending on the motor
speed, the output torque of the inverter can be adjusted by setting the
frequency at which the load value becomes large and adjusting the
voltage at that frequency.
0
VC
VP(f )
1.7
(a) (b)
(c)
Output frequency
[Hz]
Maximum
frequency
Base
frequency
Output
voltage
(100%)
10% of base
frequency