Long return time
Overshoot or unstable
You can switch between PI control and P control under speed control using the X44 signal. (Refer to page 37.)
Motor does not rotate.
Motor does not run at
(Speed command does
not match actual speed)
Set the Pr. 821 value a little lower.
Decrease the value by half until just before an overshoot or the unstable phenomenon does
not occur, and set about 0.8 to 0.9 of that value.
Set the Pr. 821 value a little higher.
Double the value until just before an overshoot or the unstable phenomenon does not occur,
and set about 0.8 to 0.9 of that value.
(1) The motor or encoder wiring is
(2) The encoder specifications
(jumper connector setting) are
(3) The encoder wiring is wrong.
(4) The Pr. 851 "number of encoder
pulses" setting and the number of
encoder used are different.
(1) The speed command from the
command device is incorrect.
The speed command is
compounded with noise.
(2) The speed command value does
not match the inverter-recognized
(3) The number of encoder pulses
setting is incorrect.
Fine adjustment of gains for speed control
(1) Check the wiring.
* Choose V/F control (Pr. 800 = 20) and check the
rotation direction of the motor and the speed monitor
output from the DA1 output terminal.
When the forward rotation signal is
input, the motor running in the
counterclockwise direction as viewed
from the motor shaft is normal. (If it runs
in the clockwise direction, the phase
sequence of the inverter secondary side
wiring is incorrect.)
(2) Check the encoder specifications.
Check the positions of the 5V/12V/24V/External
and differential/complimentary jumper connectors.
(3) Check that FWD is displayed when running the
motor in the counter-clockwise direction from
outside during a stop of the inverter.
If REV is displayed, the encoder phase sequence
is wrong. Perform the correct wiring or match the
Pr. 852 "encoder rotation direction" setting.
Relationship between the motor and
Forward rotation is clockwise rotation
when viewed from A.
Forward rotation is counterclockwise rotation
when viewed from A.
(4) The motor will not run if the parameter setting is
smaller than the number of encoder pulses used.
Set Pr. 851 "number of encoder pulses" correctly.
(1) Check that a correct speed command comes from
the command device.
Decrease the PWM carrier frequency in Pr. 72.
(2) Readjust the speed command bias and gain in Pr.
902, Pr. 903, Pr. 917, and Pr. 918.
(3) Check the setting of the number of encoder pulses
in Pr. 851.