254
Check first when you have a trouble
5.5.12 Speed does not accelerate
5.5.13 Unable to write parameter setting
Check
points
Possible Cause Countermeasures
Refer
to
page
Input
signal
Start command and speed command are chattering.
Check if the start command and the speed command
are correct.
—
The wiring length used for analog speed command is
too long, and it is causing a voltage (current) drop.
Perform analog input bias/gain calibration. 135
Input signal lines are affected by external EMI.
Take countermeasures against EMI, such as using
shielded wires for input signal lines.
36
Parameter
Setting
Pr. 1, Pr. 2, calibration parameter C2 to C7 settings are
improper.
Check the settings of Pr. 1Maximum setting and Pr. 2
Minimum setting.
78
Check the calibration parameter C2 to C7 settings. 135
The maximum speed is limited to the maximum speed of
the PM motor (3000r/min).
272
The maximum voltage (current) input value is not set
during the External operation. (Pr. 125, Pr. 126)
Check the Pr. 125 Terminal 2 speed setting gain speed and
Pr. 126 Terminal 4 speed setting gain speed settings.
78 135
Stall prevention function is activated due to a heavy
load.
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 overcurrent trip (E.OC).)
74
Check the capacities of the drive unit and the motor. —
During PID control, rotation speed is automatically controlled to make measured value = set point. 199
Main
Circuit
Brake resistor is connected between terminal P/+ and
P1 by mistake.
Connect an optional brake transistor (MRS type, MYS
type, FR-ABR) between terminal P/+ and PR.
27
Check
points
Possible Cause Countermeasures
Refer
to
page
Input
signal
Operation is being performed (signal STF or STR is
ON).
Stop the operation.
When Pr. 77 = "0" (initial value), write is enabled only
during a stop.
143
Parameter
Setting
You are attempting to set the parameter in the External
operation mode.
Choose the PU operation mode.
Or, set Pr. 77 = "2" to enable parameter write regardless
of the operation mode.
143
Parameter is disabled by the Pr. 77 Parameter write
selection setting.
Check Pr. 77 Parameter write selection setting. 143
Key lock is activated by the Pr. 161 Speed setting/key lock
operation selection setting.
Check Pr. 161 Speed setting/key lock operation selection
setting.
225
Operation mode and a writing device do not
correspond.
Check Pr. 79, Pr. 338, Pr. 339, Pr. 551, and select an
operation mode suitable for the purpose.
147,
160
