Mitsubishi FR-A740-00023-EC, Instruction Manual

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Operation selection at power failure
and instantaneous power failure
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
made invalid.)
Encoder detection frequency search
⋅
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" 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 serch)
V/F control, advanced magnetic flux vector control
Real sensorless vector control
Coasting time
Pr.57 setting
*
Instaneous (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
*
Instaneous (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.
REMARKS
⋅
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
(Pr.57)
* 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)
REMARKS
⋅
When encoder feedback control is invalid, setting "2 or 12" in Pr.
162 enables frequency search ( Pr. 162 = "0, 10").