Speed Does Not Accelerate; Unable To Write Parameter Setting; Unable To Establish Ethernet Communication - Mitsubishi Electric 800 Series Instruction Manual

2.6.12 Speed does not accelerate

Check
point
The start command or frequency
command is chattering.
The wiring length is too long for the
Input
analog frequency command, causing a
signal
voltage (current) drop.
The input signal lines are affected by
external EMI.
Pr.1 Maximum frequency, Pr.2
Minimum frequency, Pr.18 High speed
maximum frequency, and the
calibration parameter C2 to C7 settings
are not appropriate.
The maximum voltage (current) input
value is not set during the External
operation. (Pr.125, Pr.126, Pr.18)
The torque boost (Pr.0, Pr.46) setting is
not appropriate under V/F control, so the
stall prevention function is activated.
Parameter
The V/F pattern is not appropriate when
setting
V/F control is performed. (Pr.3, Pr.14,
Pr.19)
The stall prevention (torque limit) function
is activated due to a heavy load.
Auto tuning is not performed under
Advanced magnetic flux vector control or
Real sensorless vector control.
During PID control, the output frequency is automatically controlled so that the measured value equals the set point.
A brake resistor is connected across
Main
terminals P/+ and P1 or across P1 and
circuit
PR by mistake.

2.6.13 Unable to write parameter setting

Check
point
Input Operation is being performed (the STF or
signal STR signal is ON).
Parameter setting was attempted in the
External operation mode.
Parameter write is disabled by the Pr.77
Parameter write selection setting.
Parameter
The key lock mode is enabled by the
setting
Pr.161 Frequency setting/key lock
operation selection setting.
Operation mode and a writing device do
not correspond.

2.6.14 Unable to establish Ethernet communication

40
2. Protective Functions
2.6 Check first when you have a trouble
Possible cause
Possible cause
Check if the start command and the frequency command are correct.
Perform the bias and gain calibration for the analog input.
Take countermeasures against EMI, such as using shielded wires for input signal
lines.
Check the settings of Pr.1 and Pr.2. To operate at 120 Hz or higher, set Pr.18 High
speed maximum frequency.
Check the calibration parameter C2 to C7 settings.
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.
Increase/decrease the Pr.0 Torque boost setting value by 0.5% increments so that
stall prevention does not occur.
Set the 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).
Change the Pr.14 Load pattern selection setting 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 motor.
Perform offline auto tuning.
Connect an optional brake resistor (FR-ABR) across terminals P/+ and PR.
Stop the operation. When Pr.77 Parameter write selection = "0 (initial value)",
writing is enabled only during a stop.
Choose the PU operation mode. Or, set Pr.77 Parameter write selection = "2" to
enable parameter writing regardless of the operation mode.
Check the Pr.77 setting.
Check the Pr.161 setting.
Check Pr.79, Pr.338, Pr.339, Pr.550 and Pr.551, and select an operation mode
suitable for the purpose.
Countermeasure
Countermeasure