152
Operation selection at power failure and
instantaneous power failure
4.12 Operation selection at power failure and instantaneous
power failure
4.12.1 Automatic restart after instantaneous power failure / flying start
(Pr. 57, Pr. 58, Pr. 162 to Pr. 165, Pr. 299, Pr. 611)
Purpose Parameter that must be Set Refer to Page
At instantaneous power failure
occurrence, restart inverter without
stopping motor
Automatic restart operation
after instantaneous power
failure / flying start
Pr. 57, Pr. 58, Pr. 162 to Pr. 165,
Pr. 299, Pr. 611 152
When undervoltage or a power
failure occurs, the inverter can be
decelerated to a stop.
Power failure-time
deceleration-to-stop
function
Pr. 261 to Pr. 266 156
You can restart the inverter without stopping the motor in the following cases.
⋅when bypass operation is switched to inverter operation
⋅when power comes back ON after an instantaneous power failure
⋅when motor is coasting at start
Parameter
Number Name
Initial Value
200V class
(400V class)
Setting Range
200V class
(400V class)
Description
200V class (400V class)
57 Restart coasting
time 9999
0
FR-F720-00077 (FR-F740-00038) or less.... 0.5s
FR-F720-00105 to 00340
(FR-F740-00052 to 00170)..........................1s
FR-F720-00490 to 02330
(FR-F740-00250 to 01160) .........................3.0s
FR-F720-03160 (FR-F740-01800) or more ..5.0s
The above times are coasting time.
02330 (01160)
or less
0.1 to
5s Set the waiting time for inverter-triggered restart
after an instantaneous power failure.
03160 (01800)
or more
0.1 to
30s
9999 No restart
58 Restart cushion
time 1s 0 to 60s Set a voltage starting time at restart.
162
Automatic
restart after
instantaneous
power failure
selection
0
0 With frequency search
1Without frequency search (Reduced voltage
system)
10 Frequency search at every start
11 Reduced voltage system at every start
163 First cushion
time for restart 0s 0 to 20s Set a voltage starting time at restart.
Consider using these parameters according to the
load (moment of inertia, torque) magnitude.
164
First cushion
voltage for
restart
0% 0 to 100%
165
Stall prevention
operation level
for restart
110%*1 0 to 120%*1
Considers the rated inverter current as 100% and
set the stall prevention operation level during
restart operation.
299
Rotation
direction
detection
selection at
restarting
9999
0Without rotation direction detection
1With rotation direction detection
9999
When Pr. 78="0", the rotation direction is detected.
When Pr. 78="1", "2", the rotation direction is not
detected.
611 Acceleration
time at a restart
02330 (01160)
or less
5s
0 to 3600s, 9999
Set the acceleration time to reach Pr. 20
Acceleration/deceleration reference frequency at a
restart.
Acceleration time for restart is the normal acceleration
time (e.g. Pr. 7) when "9999" is set.
03160 (01800)
or more
15s
The above parameters can be set when Pr. 160 User group read selection = "0". (Refer to page 190)
*1 When
Pr. 570 Multiple rating setting
= "1", performing inverter reset and all parameter clear changes the initial value and setting range.
(Refer to page 86.)