Mitsubishi Electric 800 Series, Instruction Manual, Page: 685 / 727

684
APPENDIX
Appendix 3
Specification comparison between
PM sensorless vector control and
induction motor control

For the motor capacity, the rated motor current should be equal to or less than the inverter rated current. (It must be 0.4 kW or higher.)
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
• Before wiring, make sure that the motor is stopped. Otherwise you may get an electric shock.
• Never connect a PM motor to the commercial power supply.
• No slippage occurs with a PM motor because of its characteristic. If a PM motor, which took over an induction motor, is driven
at the same speed as for the general-purpose motor, the running speed of the PM motor becomes faster by the amount of the
general-purpose motor's slippage. Adjust the speed command to run the PM motor at the same speed as the induction motor,
as required.
Item PM sensorless vector control Induction motor control
Applicable motor
PM motor (tuning required)

Induction motor

Starting torque
50%
200% (FR-A860-00090 or lower)
150% (FR-A860-00170 or higher)
under Real sensorless vector control
and vector control
Zero speed
Not available
Available under Real sensorless vector control and
vector control
Carrier frequency
2 kHz ( Pr.72 = "0 to 5"), 6 kHz ( Pr.72 = "6 to 9"),
10 kHz ( Pr.72 = "10 to 13"),
14 kHz ( Pr.72 = "14 or 15")
(6 kHz in a low-speed range of 10 kHz or higher.)
Any value in the range of 0.75 kHz to 14.5 kHz
(FR-A860-01080 or lower)
0.75 kHz to 6 kHz
(FR-A860-01440 or higher)
Startup delay
Startup delay of about 0.1 s for magnetic pole
position detection. No startup delay (when online auto tuning is not
performed at startup).
Driving by the commercial
power supply
Cannot be driven by the commercial power supply.
Can be driven by the commercial power supply.
(Other than vector control dedicated motor.)
Operation during coasting
While the motor is coasting, potential is generated
across motor terminals. While the motor is coasting, potential is not
generated across motor terminals.
Torque control
Not available
Available under Real sensorless vector control and
vector control.
Position control
Not available Available under vector control.