Acceleration/Deceleration Is Not Smooth - Mitsubishi Electric FR-A820-00046 (0.4K) Instruction Manual

6.6.7

Acceleration/deceleration is not smooth

Check
point
The acceleration/deceleration time is too
short.
The torque boost (Pr.0, Pr.46, Pr.112)
setting is not appropriate under V/F control,
so the stall prevention function is activated.
Parameter
setting
The base frequency does not match the
motor characteristics.
Regeneration avoidance operation is
performed.
Load
Parameter The stall prevention (torque limit) function is
setting activated due to a heavy load.
Motor
770
6. PROTECTIVE FUNCTIONS
6.6 Check first when you have a trouble
Possible cause Countermeasure
Increase the acceleration/deceleration time.
Increase/decrease the Pr.0 Torque boost setting value by 0.5%
increments so that stall prevention does not occur.
Under V/F control, set Pr.3 Base frequency, Pr.47 Second V/F
(base frequency), and Pr.113 Third V/F (base frequency).
Under Vector control, set Pr.84 Rated motor frequency.
If the frequency becomes unstable during regeneration avoidance
operation, decrease the setting of Pr.886 Regeneration
avoidance voltage gain.
Reduce the load.
Set Pr.22 Stall prevention operation level (Torque limit level)
higher according to the load. (If Pr.22 is set too high, an overcurrent
trip (E.OC[]) is likely to occur.)
Check the capacities of the inverter and the motor.
Refer to
page
349
672
673
215
696
—
235, 409
—