Mitsubishi Electronics FR-A700 ユーザーズマニュアル

Without frequency search
When  Pr. 162  = "1" or "11", automatic restart operation is

performed in a reduced voltage system, where the voltage is

gradually risen with the output frequency unchanged from prior

to an instantaneous power failure independently of the

coasting speed of the motor.

For Real sensorless vector control, output frequency and

voltage before instantaneous power failure are output. (Pr. 58 is

invalid.)

⋅ When "2 or 12" is set in Pr. 162 under encoder feedback

control, the motor starts at the motor speed and in the rotation

direction detected from the encoder at power restoration.

⋅ Encoder detection frequency search is performed regardless

of the Pr. 162 setting under vector control.

⋅ The Pr. 58 and Pr. 299 settings are invalid for encoder detection

frequency search.

Restart operation at every start
When  Pr. 162 = "10, 11 or 12", automatic restart operation is

also performed every start, in addition to the automatic restart

after instantaneous power failure. When Pr. 162 = "0, 1 or 2",

automatic restart operation is performed at the first start after

power supply-on, but the inverter starts at the starting

frequency at the second time or later.

When Pr. 162 = 1, 11 (without frequency search)

V/F control, Advanced magnetic flux vector control

Real sensorless vector control

Coasting time
Pr.57 setting

*

Instantaneous (power failure) time

Power supply
(R/L1, S/L2, 
T/L3)

Motor speed N 
(r/min)

Inverter output 
frequency f(Hz)

Inverter output 
voltage E(V)

Restart cushion time
(Pr.58 setting)

*  The output shut off timing differs 

according to the load condition.

Coasting time
Pr.57 setting

*

Instantaneous (power failure) time

Power supply
(R/L1, S/L2, 
T/L3)

Motor speed N 
(r/min)

Inverter output 
frequency f(Hz)
output voltage 
E(V)

*  The output shut off timing differs 

according to the load condition.

⋅ This system stores the output frequency prior to an

instantaneous power failure and increases the voltage.
Therefore, if the instantaneous power failure time exceeds 0.2s,
the inverter starts at Pr. 13 Starting frequency (initial value = 0.5Hz)
since the stored output frequency cannot be retained.

Instantaneous 

(power failure) time

Power supply
(R/L1, S/L2, T/L3)

Motor speed N
(r/min)

Inverter output 
frequency f(Hz)
Output voltage E(V)

Coasting time

* The output shut off timing differs according to the load condition.

*

Acceleration time 

at a restart 

(Pr.611 setting)

When  Pr. 162 = 2, 12 (encoder detection

frequency search)

⋅ When encoder feedback control is invalid, setting "2 or 12" in Pr.

162 enables frequency search (Pr. 162 = "0, 10").