Mitsubishi Electric FR-A700 Series, Technical Manual

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375
PARAMETER
2
P
ARAM
ETE
R
(4) Operation continuation function at
instantaneous power failure [Pr. 261 = 2,
12
* ]
(*not available for )
When power is restored during deceleration after a
power failure, acceleration is made again up to the
set frequency.
* Acceleration time follows the [ Pr. 7 ] ([ Pr. 44 ]) setting.
When this function is used in combination with the
automatic restart after instantaneous power failure
operation, deceleration can be made at a power
failure and acceleration can be made again after
power restoration. When power is restored after a
stop by deceleration at an instantaneous power
failure, automatic restart operation is performed if
automatic restart after instantaneous power failure
has been selected [
Pr. 57
≠
"9999"]
Keep start signal (STF/STR) ON during
instantaneous power failure when using operation
continuation function at instantaneous power failure.
When start signal turns OFF during instantaneous
power failure, the inverter decelerates by the
deceleration time setting. If regeneration energy is
insufficient, the motor coasts.
(5) Undervoltage avoidance function [Pr. 261
= 11, 12, Pr. 294]
When [ Pr. 261 = 11, 12], the deceleration time is
automatically adjusted (shortened) to prevent
undervoltage from occurring during deceleration at
an instantaneous power failure.
Adjust the slope of frequency decrease and response
level with [
Pr. 294 ]. A larger setting will improve
responsiveness to the bus voltage. Since the
regeneration amount is large when the inertia is
large, decrease the setting value.
Undervoltage avoidance function is invalid during
torque control by Real sensorless vector control.
When [
Pr. 261 = 11 (12)], the inverter operates in the
same manner as when [ Pr. 261 = 1 (2)].
(6) Power failure deceleration signal (Y46
signal)
After deceleration at an instantaneous power failure,
inverter can not start even if the start command is
given. In this case, check the power failure
deceleration signal (Y46).
The Y46 signal is ON during deceleration at an
instantaneous power failure or during a stop after
deceleration at an instantaneous power failure.
For the Y46 signal, set 46 (positive logic) or 146
(negative logic) in any of [
Pr. 190 to Pr. 196 (output
terminal function selection ] to assign the function.
F700 E700 D700
IPF
Power
supply
Time
Output
frequency
Y46
During deceleration
at occurrence of
power failure
Re-acceleration*
When power is restored during
deceleration at occurrence of
power failure
[ Pr. 261 = 2]
During power failure
Power
supply
Output
frequency
Y46
During deceleration
at occurrence of
power failure
Automatic restart
after instantaneous
power failure
Reset time + [ Pr.57 ]
[
Pr.261
= 2], [
Pr.57
9999]
When used with automatic restart
after instantaneous power failure
Time
A700