Check first when you have troubles
Acceleration/deceleration is not smooth
Check points Possible Cause
7 - 24
Acceleration/deceleration time is too
Torque boost (Pr. 0, Pr. 46) setting is
improper under V/f control, so the stall
prevention function is activated.
The base frequency does not match the
Stall prevention function is activated due
to a heavy load.
Regeneration avoidance operation is per-
Increase acceleration/deceleration time.
Increase/decrease Pr. 0 "Torque boost"
setting value by 0.5% increments to the
For V/f control, set Pr. 3 "Base frequency"
and Pr. 47 "Second V/f (base frequency)".
For Advanced magnetic flux vector control
or General-purpose magnetic flux vector
control, set Pr. 84 "Rated motor fre-
Reduce the load weight.
Set Pr. 22 "Stall prevention operation level
"higher according to the load. (Setting Pr.
22 too large may result in frequent over-
current trip (E.OC ).)
Check the capacities of the inverter and
If the frequency becomes unstable during
regeneration avoidance operation,
decrease the setting of Pr. 886 "Regene-
ration avoidance voltage gain".