Mitsubishi Electronics FR-A701 ユーザーズマニュアル

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BCN-C22005-675

For the FR-A701 series manufactured in January 2015 or later, the following specifications are added.
Check the year and month of manufacture by the SERIAL number printed on the rating plate of the
inverter.

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SERIAL number check

Refer to the inverter manual for the location of the rating plate.

In the following sections, 

 indicates the functions that are driven by PM sensorless vector control.

Highly efficient motor control and highly accurate motor speed control can be performed by using the inverter with an
IPM (internal permanent magnet) motor, which is more efficient than an induction motor.
The motor speed is calculated based on the output voltage and current from the inverter. It does not require a speed
detector such as an encoder. The inverter drives the IPM motor with the least required current when a load is applied
in order to achieve the highest motor efficiency.

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Symbol Year

Month

Control number

SERIAL

The SERIAL consists of one symbol, two characters indicating production 
year and month, and six characters indicating control number. 
The last digit of the production year is indicated as the Year, and the Month 
is indicated by 1 to 9, X (October), Y (November), or Z (December).

To perform IPM parameter initialization

IPM parameter initialization

Pr. 998

To select the torque characteristic in a 
low-speed range

Low-speed range torque 
characteristics

Pr. 788

To adjust the gain for PM sensorless 
vector control

Adjusting the speed control 
gain

Pr. 820, Pr. 821

The following conditions must be met to perform PM sensorless vector control.

· For the motor model, IPM motor must be used.

· The motor capacity must be equal to or one rank lower than the inverter capacity.

· Single-motor operation (one motor run by one inverter) must be performed.

· The overall wiring length with the motor must be 100m or less. (When the wiring length exceeds 30m,

offline auto tuning must be performed.)

· The speed setting range for an MM-CF IPM motor is between 0 and 200Hz.
· The carrier frequency is limited during PM sensorless vector control. (Refer to page 17)
· Constant-speed operation cannot be performed in the low-speed range of 200r/min or less under current

synchronization operation. (Refer to page 14)

· During PM sensorless vector control, the RUN signal is output about 100ms after turning ON the start command (STF,

STR). The delay is due to the magnetic pole detection.

· During PM sensorless vector control, the automatic restart after instantaneous power failure function operates only

when an MM-CF IPM motor is connected. However, the frequency search may not be available at 2200 r/min or
above. The restart operation cannot be performed until the motor speed drops to a frequency where the frequency
search is available. 

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