Mitsubishi Electric FR-A700 Technical Manual page 335

(2) Automatic restart operation selection [Pr.
162, Pr. 299]
1) With frequency search
When [Pr. 162 = 0, 10] , the inverter smoothly
starts by increasing voltage up to the frequency
set in [Pr. 58 Restart cushion time] after detecting
the motor speed upon power restoration.
When performing Real sensorless vector control
on , control starts at the detected frequency
A700
([Pr. 58 Restart cushion time] is invalid).
Even when the motor is rotating in the opposite
direction, the inverter can be restarted smoothly
as the direction of rotation is detected.
When selecting frequency search in
perform offline auto tuning.
Whether to make a rotation direction detection or
not can be selected using [Pr. 299 Rotation
direction detection selection at restarting]. When
capacities of the motor and inverter differ, set [Pr.
299 = 0] (without rotation direction detection).
When reverse rotation is detected when [Pr. 78 =
1] (reverse rotation disabled), the rotation
direction is changed to forward rotation after
decelerates in reverse rotation when the start
command is forward rotation. The inverter will not
start when the start command is reverse rotation.
[Pr. 299]
Setting
9999
0 (initial value)
1
: the rotation direction is detected.
× : the rotation direction is not detected.
Speed detection time (frequency search) changes
according to the motor speed. (maximum 500ms
in , maximum 100ms in
A700 F700
When the inverter capacity is two rank or larger
than the motor capacity, the inverter may not start
due to overcurrent (OCT) alarm.
If two or more motors are connected to one
inverter, the inverter functions abnormally. (The
inverter does not start smoothly.)
Since the DC injection brake is operated
instantaneously when the speed is detected at a
restart, the speed may decrease if the load inertia
(J) is small.
When perform automatic restart after
E700 D700
instantaneous power
operation (less than 10Hz),
with the same rotation direction as before the
instantaneous power failure and does not detect
rotation direction
detection selection at restarting =1].
When result of frequency search is the setting
frequency or higher, output frequency is limited to
the set frequency.
When wiring length is longer than the values in
the table below in
frequency search" [Pr. 162=1, 11].
E700 D700
[Pr. 78] Setting
0 1 2
× ×
× × ×
)
E700 D700
failure in low speed
restart
E700 D700
[Pr. 299 Rotation direction
, select "without
E700 D700
Motor capacity
Wiring length
V/F control, Advanced magnetic flux vector
control, General-purpose magnetic flux vector
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)
Speed
Coasting
detection
+
time ([Pr. 57]) time
E700 D700
Speed
Coasting
detection
+
time ([Pr. 57]) time
A700 F700
Real sensorless vector control
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])
* The output shut off timing differs
according to the load condition.
2) Frequency not searched
When [Pr. 162 = 1, 11], automatic restart operation
is performed in a reduced voltage, where the
voltage is gradually risen with the output
frequency
instantaneous power failure independently of the
coasting speed of the motor.
When performing Real sensorless vector control
on , control starts at the output frequency
A700
before instantaneous power failure ([Pr. 58 Restart
cushion time] is invalid).
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.
369
PARAMETER
0.4K or
0.1K 0.2K
20m 50m
*
Restart cushion
time ([Pr. 58] setting)
Acceleration time
at a restart
(Accelerates by
the slope calculated
from [Pr.611] and [Pr.20].)
* The output shut off timing differs
according to the load condition.
*
Speed
detection Acceleration time
time
at a restart
(Accelerates by
the slope calculated
from [Pr.611] and [Pr.20].)
unchanged from prior
more
100m
2
to an