Mitsubishi Electronics FR-F700-NA ユーザーズマニュアル
350
Check first when you have a trouble
5.5.5
Motor rotates in the opposite direction
5.5.6
Speed greatly differs from the setting
5.5.7
Acceleration/deceleration is not smooth
Check
points
points
Possible Cause
Countermeasures
Refer
to
page
Main
Circuit
Phase sequence of output terminals U, V and W is
incorrect.
incorrect.
Connect phase sequence of the output cables (terminal
U, V, W) to the motor correctly
U, V, W) to the motor correctly
Input
signal
The start signals (forward rotation, reverse rotation) are
connected improperly.
connected improperly.
Check the wiring. (STF: forward rotation , STR: reverse
rotation)
rotation)
The polarity of the frequency command is negative
during the polarity reversible operation set by Pr. 73
Analog input selection.
during the polarity reversible operation set by Pr. 73
Analog input selection.
Check the polarity of the frequency command.
Check
points
points
Possible Cause
Countermeasures
Refer
to
page
Input
signal
Frequency setting signal is incorrectly input.
Measure the input signal level.
—
The input signal lines are affected by external EMI.
Take countermeasures against EMI such as using
shielded wires for input signal lines.
shielded wires for input signal lines.
Parameter
Setting
Pr. 1, Pr. 2, Pr. 18, calibration parameter C2 to C7 settings
are improper.
are improper.
Check the settings of Pr. 1 Maximum frequency, Pr. 2
Minimum frequency, Pr. 18 High speed maximum frequency.
Minimum frequency, Pr. 18 High speed maximum frequency.
Check the calibration parameter C2 to C7 settings.
Pr. 31 to Pr. 36 (frequency jump) settings are improper.
Narrow down the range of frequency jump.
Load
Stall prevention function is activated due to a heavy
load.
load.
Reduce the load weight.
—
Parameter
Setting
Set Pr. 22 Stall prevention operation level higher according
to the load. (Setting Pr. 22 too large may result in
frequent overcurrent trip (E.OC ).)
to the load. (Setting Pr. 22 too large may result in
frequent overcurrent trip (E.OC ).)
Motor
Check the capacities of the inverter and the motor.
—
Check
points
points
Possible Cause
Countermeasures
Refer
to
page
Parameter
Setting
Acceleration/deceleration time is too short.
Increase acceleration/deceleration time.
Torque boost (Pr. 0, Pr. 46) setting is improper under V/F
control, so the stall prevention function is activated.
control, so the stall prevention function is activated.
Increase/decrease Pr. 0 Torque boost setting value by
0.5% increments to the setting.
0.5% increments to the setting.
The base frequency does not match the motor
characteristics.
characteristics.
Set Pr. 3 Base frequency and Pr. 47 Second V/F (base
frequency).
frequency).
Regeneration avoidance operation is performed
If the frequency becomes unstable during regeneration
avoidance operation, decrease the setting of Pr. 886
Regeneration avoidance voltage gain.
avoidance operation, decrease the setting of Pr. 886
Regeneration avoidance voltage gain.
Load
Stall prevention function is activated due to a heavy
load.
load.
Reduce the load weight.
—
Parameter
Setting
Set Pr. 22 Stall prevention operation level higher according
to the load. (Setting Pr. 22 too large may result in
frequent overcurrent trip (E.OC ).)
to the load. (Setting Pr. 22 too large may result in
frequent overcurrent trip (E.OC ).)
Motor
Check the capacities of the inverter and the motor.
—