Mitsubishi Electric FR-A800 Series Instruction Manual page 803

Check
point
Two-wire or three-wire type connection is
incorrect.
Under V/F control, Pr.0 Torque boost
setting is not appropriate.
Pr.78 Reverse rotation prevention
selection is set.
The Pr.79 Operation mode selection
setting is incorrect.
The bias and gain (the calibration
parameter C2 to C7) settings are not
appropriate.
The Pr.13 Starting frequency setting is
greater than the set frequency.
Zero is set in frequency settings (such as for
multi-speed operation).
Especially, Pr.1 Maximum frequency is
zero.
Pr.15 Jog frequency is lower than Pr.13
Starting frequency for JOG operation.
The Pr.359 (Pr.852) Encoder rotation
direction setting is incorrect under encoder
feedback control or under vector control.
When a Vector control option is used, the
option to be used and parameter settings do
not match.
Parameter
Operation mode and a writing device do not
setting
correspond.
The start signal operation selection is set by
Pr.250 Stop selection
The motor has decelerated to a stop when
the power failure time deceleration-to-stop
function is selected.
Auto tuning is being performed.
The automatic restart after instantaneous
power failure function or power failure stop
function has been activated.
(Performing overload operation during input
phase loss may cause voltage insufficiency,
and that may result in detection of power
failure.)
The motor test operation is selected under
Vector control or PM sensorless vector
control.
When the FR-HC2, FR-XC, FR-CV, or FR-
CC2 is used, the input logic setting of the
X10 signal is incorrect.
Load is too heavy.
Load
The shaft is locked.
802
6. PROTECTIVE FUNCTIONS
6.6 Check first when you have a trouble
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Countermeasure
Check the connection.
Use the Start self-holding selection (STP (STOP)) signal when the
three-wire type is used.
Increase the Pr.0 setting by 0.5% increments while observing the
rotation of a motor.
If that makes no difference, decrease the setting.
Check the Pr.78 setting. Set Pr.78 when you want to limit the motor
rotation to only one direction.
Select the operation mode suitable for the input methods of the start
command and frequency command.
Check the bias and gain (the calibration parameter C2 to C7)
settings.
Set the frequency higher than the one set in Pr.13.
The inverter does not start if the frequency setting signal has a
value lower than that of Pr.13.
Set the frequency command according to the application. Set Pr.1
higher than the actual frequency used.
The Pr.15 setting should be equal to or higher than the Pr.13
setting.
If the REV indicator on the operation panel is ON even though the
forward-rotation command is given, set Pr.359 (Pr.852) = "1".
Correctly set Pr.862 Encoder option selection according to the
option to be used.
Check Pr.79 Operation mode selection, Pr.338 Communication
operation command source, Pr.339 Communication speed
command source, Pr.550 NET mode operation command
source selection and Pr.551 PU mode operation command
source selection, and select an operation mode suitable for the
purpose.
Check the Pr.250 setting and the connection of the STF and STR
signals.
When power is restored, ensure the safety, and turn OFF the start
signal once, then turn ON again to restart. When Pr.261 Power
failure stop selection = "2 or 12", the motor automatically restarts
after the power is restored.
When offline auto tuning ends, press the
operation panel for the PU operation. For the External operation,
turn OFF the start signal (STF or STR).
This operation resets the offline auto tuning, and the PU's monitor
display returns to the normal indication.
(Without this operation, next operation cannot be started.)
Set Pr.872 Input phase loss protection selection = "1" (input
phase failure protection active).
Disable the automatic restart after instantaneous power failure
function and power failure stop function.
Reduce the load.
Increase the acceleration time if the function was activated during
acceleration.
Check the Pr.800 Control method selection setting.
Set Pr.599 = "0" (initial value for standard models and IP55
compatible models) to use the X10 signal with the NO contact input
specification, and Pr.599 = "1" (initial value for separated converter
types) to use the X10 signal with the NC contact input specification.
Reduce the load.
Inspect the machine (motor).
Refer to
page
722
706
406
389
505
381, 367
411, 428
381, 382,
410
94, 736
226
389, 400
722
642
key of the
532, 542,
551, 638
426, 628,
635, 642
221
724
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