Check first when you have a trouble
Speed does not accelerate
6 - 44
Start command and frequency command
The wiring length used for analog
frequency command is too long, and it is
causing a voltage (current) drop.
The input signal lines are affected by
Pr. 1 "Maximum frequency", Pr. 2 "Minimum
frequency", Pr. 18 "High speed maximum
frequency", and calibration parameter C2 to
C7 settings are improper.
The maximum voltage (current) input value
is not set during the External operation.
(Pr. 125, Pr. 126, Pr. 18)
Torque boost (Pr. 0, Pr. 46, Pr. 112) setting is
improper under V/F control, so the stall
prevention function is activated.
V/F pattern is improper when V/F control is
(Pr. 3, Pr. 14, Pr. 19)
Stall prevention (torque limit) function is
activated due to a heavy load.
Auto tuning is not performed under
Advanced magnetic flux vector control, Real
sensorless vector control, or vector control.
The setting of pulse train input is improper.
During PID control, output frequency is automatically controlled to make measured value =
Brake resistor is connected across terminals
P/+ and P1 or across P1 and PR by mistake.
Check if the start command and the frequency
command are correct.
Perform Analog input bias/gain calibration.
Take countermeasures against EMI, such as
using shielded wires for input signal lines.
Check the settings of Pr. 1 and Pr. 2 and set
Check the calibration parameter C2 to C7
Check the settings of Pr. 125 "Terminal 2
frequency setting gain frequency" and Pr. 126
"Terminal 4 frequency setting gain frequency".
To operate at 120 Hz or higher, set Pr. 18 "High
speed maximum frequency".
Increase/decrease the Pr. 0 "Torque boost"
setting value by 0.5% increments so that stall
prevention does not occur.
Set rated frequency of the motor to Pr. 3 "Base
Use Pr. 19 "Base frequency voltage" to set the
base voltage (for example, rated motor
Change Pr. 14 "Load pattern selection"
according to the load characteristic.
Reduce the load weight.
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
Perform offline auto tuning.
Check the specification of the pulse generator
(open collector output or complementary
output) and check the adjustment of the pulse
train and frequency (Pr. 385 "Frequency for zero
input pulse" and Pr. 386 "Frequency for
maximum input pulse").
Connect an optional brake resistor (FR-ABR)
across terminals P/+ and PR.