Set two kinds of base frequencies (Pr. 47)
Use the second base frequency when you want to change the base frequency, e.g. when using
multiple motors by switching between them by one inverter.
Pr. 47 "Second V/f (base frequency)" is valid when the RT signal is on.
The RT signal acts as the second function selection signal and makes the other second
Set "3" in any of Pr. 178 to Pr. 184 "Input terminal function selection" and assign the RT
Base frequency voltage setting (Pr. 19)
Use Pr. 19 "Base frequency voltage" to set the base voltage (e.g. rated motor voltage). If the set-
ting is less than the power supply voltage, the maximum output voltage of the inverter is as set
in Pr. 19.
Pr. 19 can be utilized in the following cases:
● When regeneration frequency is high (e.g. continuous regeneration)
During regeneration, the output voltage becomes higher than the reference and may cause
an over current trip (E.OC ) due to an increased motor current.
● When power supply voltage variation is large
When the power supply voltage exceeds the rated voltage of the motor, speed variation or
motor overheat may be caused by excessive torque or increased motor current.
When advanced magnetic flux vector control or general-purpose magnetic flux vector control
is selected, Pr. 3, Pr. 47 and Pr. 19 are invalid and Pr. 83 and Pr. 84 are valid.
Note that Pr. 3 or Pr. 47 value is made valid as inflection points of S-pattern when Pr. 29
"Acceleration/deceleration pattern selection" = 1 (S-pattern acceleration/deceleration A).
Changing the terminal assignment using Pr. 178 to Pr. 184 "Input terminal function selec-
tion" may affect the other functions. Make setting after confirming the function of each termi-
Note that the output voltage of the inverter cannot exceed the power supply voltage.
Set V/f pattern
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