Mitsubishi Electric 800 Series, Instruction Manual, Page: 447 / 727

(C) Motor constant parameters
446
PARAMETERS
NOTE
• Even if the start signal is turned ON during zero speed control or servo lock, tuning is performed at startup.
• The Y39 signal remains ON as long as there is second flux even after the motor is stopped.
• The X28 signal is disabled while the Y39 signal is ON.
• The STF and STR signals are enabled after completing tuning at start.
• The Inverter running (RUN) signal is not turned ON during online auto tuning. The RUN signal is turned ON after starting up.
• It is disabled during V/F control or PM sensorless vector control.
• Changing the terminal assignment using
Pr.178 to Pr.189 (Input terminal function selection) and Pr.190 to Pr.196
(Output terminal function selection) may affect other functions. Set parameters after confirming the function of each
terminal.
 Magnetic flux observer (tuning always) (setting value "2")
• If vector control is performed using a motor with an encoder, this setting improves torque accuracy.
Estimate or measure the flux within the motor using the current running through the motor and the inverter output voltage.
Because the flux of a motor can always be accurately estimated (even during operation), fine characteristics can always be
attained without being affected by temperature change in the second resistance.
• When vector control ( Pr.80, Pr.81 or Pr.800 ) is used, select the magnetic flux observer. (Refer to page 137 .)
• Make sure to perform offline auto tuning before performing online auto tuning.
 Tuning the second applied motor (Pr.574)
• When switching two different motors by one inverter, set the second motor in Pr.450 Second applied motor . (In the initial
setting, no second motor is applied. (Refer to page 423 .))
Pr.574 is enabled when the Second function selection (RT) signal is turned ON.

If a motor with substantially low rated current compared with the inverter rated current is used, speed and torque accuracies may deteriorate due
to torque ripples, etc. Set the rated motor current to about 40% or higher of the inverter rated current.
NOTE
• The RT signal is a second function selection signal. The RT signal also enables other second functions. (Refer to page 415 .)
The RT signal is assigned to the terminal RT in the initial status. Set "3" in any of Pr.178 to Pr.189 (Input terminal function
selection) to assign the RT signal to another terminal.
• Changing the terminal assignment using Pr.178 to Pr.189 (Input terminal function selection) may affect the other
functions. Set parameters after confirming the function of each terminal.
??????? Parameters referred to
Pr.9 Electronic thermal O/L relay page 317
Pr.71 Applied motor page 423
Pr.80 Motor capacity page 137 , page 426 , page 436
Pr.81 Number of motor poles page 137 , page 426 , page 436
Pr.96 Auto tuning setting/status page 426 , page 436
Pr.178 to Pr.189 (Input terminal function selection) page 415
Pr.190 to Pr.196 (Output terminal function selection) page 370
Pr.800 Control method selection page 137
5.13.5
Signal loss detection of encoder signals

The setting is available when a Vector control compatible plug-in option is installed.

These parameters are available when the control terminal option (FR-A8TP) is installed.
Pr. Description
450 Applicable motor
453 Motor capacity (with the rated motor current equal to or lower than the inverter rated current)

454 Number of motor poles
If encoder signals are disconnected during encoder feedback control, orientation control or vector control, Signal loss
detection (E.ECT) is turned ON to shut off the inverter output.
Pr. Name Initial value Setting range Description
376
C148

855
C248

Encoder signal loss detection
enable/disable selection
0
0 Signal loss detection disabled
1 Signal loss detection enabled
V/F V/F V/F Magnetic flux Magnetic flux Magnetic flux Vector Vector Vector