Mitsubishi FR-A800

(C) Motor constant parameters
PARAMETERS
455
5
GROUP
C
Before performing offline auto tuning
Check the following points before performing offline auto tuning.
• The PM sensorless vector control is selected.
• A motor is connected. Note that the motor should be at a stop at a tuning start. (The motor should not be rotated by the
force applied from outside during the tuning.)
• For the motor capacity, the rated motor current should be equal to or less than the rated inverter current. (It must be 0.4 kW
or higher.) If a motor with substantially low rated current compared with the rated inverter 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 rated
inverter current.
• The maximum frequency under PM sensorless vector control is 400 Hz.
• The motor may rotate slightly even if the offline auto tuning without motor rotation (Pr.96 Auto tuning setting/status = "1
or 11") is selected. (It does not affect the tuning performance.) Fix the motor securely with a mechanical brake, or before
tuning, make sure that it is safe even if the motor rotates. (Caution is required especially in vertical lift applications.)
• Offline auto tuning is not performed correctly when the surge voltage suppression filter (FR-ASF-H/FR-BMF-H) are inserted
between the inverter and motor. Be sure to remove them before performing tuning.
• Tuning is not available during position control under PM sensorless vector control.
Setting
• To perform tuning, set the following parameters about the motor.
 Set Pr.71 Applied motor according to the motor to be used. According to the Pr.71 setting, the range of the motor constant parameter setting
values and units can be changed. (For other setting values of Pr.71, refer to page 438.)
NOTE
• If PM sensorless vector control is performed, tuning cannot be performed even when Pr.96 = "101" is set. If MM-CF is set to
the applied motor, tuning cannot be performed even when Pr.96 = "1, 101" is set.
• For the tuning accuracy improvement, set the following parameter when the motor constant is known in advance.
 The setting is valid only when both of the Pr.707 (Pr.744) and Pr.724 (Pr.745) settings are other than "9999".
First
motor Pr.
Second
motor Pr.
Name Setting for a PM motor other than MM-CF Setting for MM-CF
80 453 Motor capacity Motor capacity (kW)
Set by the IPM parameter
initialization (Refer to
page 173.)
81 454 Number of motor poles The number of motor poles (2 to 12)
9 51 Electronic thermal O/L relay Rated motor current (A)
84 457 Rated motor frequency Rated motor frequency (Hz)
83 456 Rated motor voltage Rated motor voltage (V)
Rated motor voltage (V)
written on the rated plate
71 450 Applied motor
8090, 8093 (IPM motor)
9090, 9093 (SPM motor)

330 and 333
96 463 Auto tuning setting/status 1 11
Motor
Pr.71 setting
Motor constant
parameter , mH and A
unit setting
Motor constant
parameter Internal data
setting
IPM motor
MM-CF 330 333 (334)
Other than MM-CF 8090 8093 (8094)
SPM motor 9090 9093 (9094)
First
motor Pr.
Second
motor Pr.
Name Setting for a PM motor other than MM-CF Setting for MM-CF
702 743 Maximum motor frequency The maximum motor frequency (Hz) 9999 (initial value)
707 744 Motor inertia (integer) Motor inertia

Jm=Pr.707  10^(- Pr.724) (kg/m
2
)
9999 (initial value)
724 745 Motor inertia (exponent)
725 746
Motor protection current
level
Maximum current level of the motor (%) 9999 (initial value)