Mitsubishi Electric FR-E720-600 Instruction Manual page 158

Operation selection at power failure and instantaneous power failure
NOTE
When automatic restart operation after instantaneous power failure is activated while the motor is running at a low speed (less
than 10Hz), the motor restarts in the direction prior to instantaneous power failure without detecting the rotation direction (Pr.
299 Rotation direction detection selection at restarting = "1").
If the frequency search result exceeds the set frequency, the output frequency is limited at the set frequency.
When the wiring length exceeds below, select without frequency search (Pr. 162 = "1, 11").
Motor capacity
Wiring length
Restart operation at every start
When Pr. 162 = "10" or "11", automatic restart operation is also performed every start, in addition to the automatic restart
after instantaneous power failure. When Pr. 162 = "0", automatic restart operation is performed at the first start after power
supply-on, but not performed at the second time or later.
Automatic restart operation selection of MRS (X10) signal
Restart operation after turning MRS (X10) signal on then off using Pr. 30 can be selected as in the table below. When
automatic restart after instantaneous power failure is selected when using the high power factor converter (FR-HC),
noramally set "2" in Pr. 30.
Pr. 30 Setting Operation after MRS and X10 Signal Turns off, on, then off.
0, 1 Start at the Pr. 13 Starting frequency.
2 Frequency search is made and starts at the coasting speed.
(2) Restart coasting time (Pr. 57)
Coasting time is the time from when the motor speed is detected until automatic restart control is started.
Set Pr. 57 to "0" to perform automatic restart operation.
The coasting time is automatically set to the value below. Generally this setting will pose no problems.
FR-E720-080 or less, FR-E740-040 or less ...... 1s
FR-E720-110 to 330, FR-E740-060 to 170 ........ 2s
FR-E720-470 or more........................................ 3s
Operation may not be performed well depending on the magnitude of the moment of inertia (J) of the load or running
frequency. Adjust the coasting time between 0.1s and 5s according to the load specifications.
(3) Restart cushion time (Pr. 58)
Cushion time is the length of time when the voltage appropriate to the voltage at the detected motor speed (output
frequency prior to instantaneous power failure when Pr. 162 = "1, 11") from 0V.
Normally the initial value need not be changed for operation, but adjust it according to the magnitude of the moment of
inertia (J) of the load or torque.
(4) Automatic restart operation adjustment (Pr. 165, Pr. 611)
Using Pr. 165, you can set the stall prevention operation level at a restart.
Using Pr. 611, you can set the acceleration time to the acceleration time reference frequency when automatic restart
operation is performed besides the normal acceleration time.
REMARKS
If the Pr. 21 Acceleration/deceleration time increments is changed, the setting increments of Pr. 611 remain unchanged.
156
0.1K 0.2K
20m (65.61feet) 50m (164.04feet)
Voltage
100%
0.4K or more
100m (323.08feet)
Pr. 58
Time