Mitsubishi Electric FR-F800, Instruction Manual

Page: 759 / 834

Protective functions Check first when you have a trouble
FR-F800 6 - 39
6.6.12 Speed does not accelerate
Check
points
Possible cause Countermeasure
Refer to
page
Input
signal
Start command and frequency command
are chattering. Check if the start command and the frequency
command are correct.
⎯
The wiring length used for analog
frequency command is too long, and it is
causing a voltage (current) drop.
Perform Analog input bias/gain calibration. 5-260
The input signal lines are affected by
external EMI. Take countermeasures against EMI, such as
using shielded wires for input signal lines.
3-6
Parameter
setting
Pr. 1 "Maximum frequency", Pr. 2 "Minimum
frequency", Pr. 18 "High speed maximum
frequency", and calibration parameter C2 to
C7 settings are improper.
Check the settings of Pr. 1 and Pr. 2 and set
Pr. 18.
5-171
Check the calibration parameter C2 to C7
settings.
5-260
The maximum voltage (current) input value
is not set during the External operation.
(Pr. 125, Pr. 126, Pr. 18)
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".
5-171,
5-260
Torque boost (Pr. 0, Pr. 46) setting is
improper under V/F control, so the stall
prevention function is activated. Increase/decrease the Pr. 0 "Torque boost"
setting value by 0.5% increments so that stall
prevention does not occur.
5-515
V/F pattern is improper when V/F control is
performed.
(Pr. 3, Pr. 14, Pr. 19)
Set rated frequency of the motor to Pr. 3 "Base
frequency".
Use Pr. 19 "Base frequency voltage" to set the
base voltage (for example, rated motor
voltage).
5-517
Change Pr. 14 "Load pattern selection"
according to the load characteristic.
5-519
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. (If Pr. 22 is set too
high, an overcurrent trip (E.OC
) is likely to
occur.)
5-175
Check the capacities of the inverter and the
motor.
⎯
Auto tuning is not performed under
Advanced magnetic flux vector control.
Perform offline auto tuning. 5-297
The setting of pulse train input is improper.
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").
5-135
During PID control, output frequency is automatically controlled to make measured value =
set point.
5-347