Mitsubishi Electric FR-D720S SC EC Instruction Manual page 278

Operation selection at power failure
● 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 (Pr. 162 = 0 or 1)
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), normally set "2" in Pr. 30.
NOTE
When output is shut off using terminal S1 and S2 in the safety stop function model, the inver-
ter restarts in the same way as when output is shut off by MRS (X10) signal.
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-D720S-070SC or less, FR-D740-036SC or less ..................... 1 s
FR-D720S-100SC, FR-D740-050SC or more ............................... 2 s
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.
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 or 11) from
0V.
Normally the initial value need not be changed for operation, but adjust it according to the mag-
nitude of the moment of inertia (J) of the load or torque.
Voltage
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 until the set frequency (Pr. 20) is reached after
automatic restart operation is performed besides the normal acceleration time.
6 - 128
Pr. 30 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.
Fig. 6-70:
Voltage rise at automatic restart
Time
Parameter
I001170E