Omron VARISPEED G7 Instruction Manual page 96

Precautions for Rotational and Stationary Autotuning
Lower the base voltage based on Fig 4.4 to prevent saturation of the Inverter's output voltage when the rated
voltage of the motor is higher than the voltage of the power supply to the Inverter. Use the following proce-
dure to perform autotuning.
1. Input the voltage of the input power supply to T1-03 (Motor rated voltage).
2. Input the results of the following formula to T1-05 (Motor base frequency):
(Base frequency from the motor's nameplate × setting of T1-03)/(Rated voltage from motor's nameplate)
3. Perform autotuning.
After completing autotuning, set E1-04 (Max. output frequency) to the base frequency from the motor's name-
plate.
Output voltage
Rated voltage from
motor nameplate
T1-03
0
Base frequency
from motor nameplate ×T1-03
Rated voltage from motor nameplate
Fig 4.4 Motor Base Frequency and Inverter Input Voltage Setting
1. When speed precision is required at high speeds (i.e., 90% of the rated speed or higher), set T1-03 (Motor
rated voltage) to the input power supply voltage × 0.9.
2. When operating at high speeds (i.e., 90% of the rated speed or higher), the output current will increase as
the input power supply voltage is reduced. Be sure to provide sufficient margin in the Inverter current.
IMPORTANT
Precautions after Rotational and Stationary Autotuning
If the maximum output frequency and base frequency are different, set the maximum output frequency (E1-
04) after autotuning.
Output frequency
Base frequency
from motor nameplate
Trial Operation Procedures
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