Omron J7 series, User Manual

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52
V/f Control
Chapter 5-2
2. With 400-V Inverters, the values for the upper limit of setting ranges and
the default settings will be twice those given in the above table.
• Set the rated motor input frequency to the maximum voltage frequency
(FMAX) while the rated motor input voltage is set to the maximum output
voltage (VMAX).
• The vertical-axis load or the load with high viscous friction may require
high torque at low speed. If the torque is insufficient at low speed,
increase the voltage in the low-speed range by 1 V, provided that no
overload (OL1 or OL2) is detected. If an overload is detected, decrease
the set values or consider the use of an Inverter model with a higher
capacity.
• The required torque of fan or pump control increases in proportion to the
square of the speed. By setting a quadratic V/f pattern to increase the
voltage in the low-speed range, the power consumption of the system will
increase.
Frequency (Hz)
Output voltage
(V)
n10(VMAX)
n13(VC)
n15(VMIN)
0 n14
(FMIN
n12
(FB)
n11
(FA)
n09
(FMA
Frequency (Hz)
Note 1. Set the parameters so that the
following condition will be satisfied.
n14
≤
n12 < n11
≤
n09
Note 2. The value set in n13 will be ignored if
parameters n14 and n12 are the same
in value.