Analog input time constant (Pr. 74)
● It is effective to eliminate noise on the frequency setting circuit.
● Increase the filter time constant if steady operation cannot be performed due to noise, etc.
A larger setting results in slower response. (The time constant can be between 0 and 8, which are
about 5 ms to 1 s.)
Analog speed command input time constant (Pr. 822, Pr. 832)
● Set the primary delay filter time constant to the external speed command (analog input com-
mand) by using Pr. 822 "Speed setting filter 1".
● To change the time constant, for example, in a case where only one inverter is used to switch
between more than one motor, use Pr. 832 "Speed setting filter 2".
● Pr. 832 "Speed setting filter 2" is enabled when the RT signal is ON.
Analog speed command input offset adjustment (Pr. 849)
● This is used to set a range in which the motor is stopped for prevention of incorrect motor
operation in a very low speed rotation by the analog input speed command.
● Regarding the Pr. 849 "Analog input offset adjustment" value 100% is 0, the offset voltage is set
as described below:
100% < Pr. 849
100% > Pr. 849
The detailed calculation of the offset voltage is as described below:
Offset voltage [V] = Voltage at the time of 100% (5 V or 10 V ) × (Pr. 849 – 100)/100
It depends on the Pr. 73 setting.
Under PID control, the analog input filter is invalid (no filter).
Parameters referred to
Pr. 125, C2 to C4
according to Pr. 125
and C2 to C4
Slope does not
(10 V or 5 V)
Pr. 849 setting
Analog input selection
(bias and gain of the terminal 2 frequency setting)
(T) Multi-Function Input Terminal Parameters
5 - 265