Mitsubishi Electric FR-A820-00046 (0.4K), Instruction Manual

Page: 788 / 1218

(A) Application parameters Parameters
5 - 586
Restart operation without frequency search (Pr. 162 = "1, 11")
When Pr. 162 = "1 or 11", reduced voltage start is used for the restart operation. In this method, the
voltage is raised gradually while keeping the output frequency level at the level before the instanta-
neous failure, regardless of the motor's coasting speed.
Restart operation with encoder detection frequency search (Pr. 162 = "2, 12")
●
When "2, 12" is set to Pr. 162 by encoder feedback control, the inverter is restarted by the motor
speed and direction of rotation that were detected by the encoder at the power restoration.
●
By encoder detection frequency search, the Pr. 299 "Rotation direction detection selection at
restarting" setting are invalid.
I002714E
Fig. 5-289: Automatic restart without frequency search (Pr. 162 = 1/11)
NOTES This restart method uses the output frequency that was active before the instantaneous power
failure stored in memory. If the instantaneous power failure time is 0.2 s or more, the output fre-
quency can no longer be stored and held in memory, so the restart is performed from Pr. 13 "Start-
ing frequency".
During Real sensorless vector control, Pr. 162 is set to "3 or 13" (reduced impact restart).
I002715E
Fig. 5-290: Restart operation with encoder detection frequency search (Pr. 162 = 2/12)
∗
Instantaneous (power failure) time
V/F control, Advanced magnetic flux vector control
Power supply
(R/L1, S/L2,
T/L3)
Motor speed N
(r/min)
Inverter output
frequency f(Hz)
Inverter output
voltage E(V)
Coasting time
Pr. 57 setting
Restart cushion time
(Pr. 58 setting)
* The output shut off timing differs according to the load condition.
∗
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 (Pr. 57)
Acceleration time
at a restart (Pr. 611)
Restart cushion time (Pr. 58)
* The output shut off timing differs according to the load condition.