Mitsubishi Electric FR-A720-0.4K Instruction Manual page 212

(3) Start-time online auto tuning from external terminal (X28 signal, Y39 signal)
(Hz)
ON
X28signal
Tuning status Completed
at starting
Tune
Y39signal
Start signal
While the motor is stopped
ON
X28 Signal OFF
Tune
Tuning status
Completed
at starting
Secondary magnetic
flux exists a few seconds
ON
OFF
Y39 signal
Y39 signal is OFF when the motor is stopped
and X28 is turned OFF. However if the
secondary magnetic flux exists after motor stop,
the signal remains ON.
OFF
Start signal
While the X28 signal is ON
ON
X28 Signal
OFF
Tuning is not performed at start since X28 signal
and Y39 signal is ON.
Tune
Tuning status
Completed
at starting
ON
OFF
Y39 signal
OFF
Start signal
Output
frequency
0Hz
REMARKS
· Start-time tuning is performed when the start signal is turned ON during zero speed control also.
· The Y39 signal is in ON status while secondary magnetic flux exists after the motor stop.
· While the Y39 signal is ON, the X28 signal is not valid.
· The STF, STR signals are valid after completion of the start-time tuning.
· The following output terminals (initial value) are valid during online auto tuning:
IPF, A1B1C1
· Tuning is invalid during V/F control.
CAUTION
· Changing the terminal assignment using Pr. 178 to Pr. 189 (input terminal function selection) or Pr. 190 to Pr. 196 (output terminal
function selection) may affect the other functions. Set parameters after confirming the function of each terminal.
Time
ON ON ON
Tune Tune
Completed
Completed
Secondary magnetic
flux exists a few seconds
ON ON
Tuning is not
performed if the
Y39 signal is ON.
Time
Selection and protection of a motor
· By turning ON the start-time tuning signal (X28) before the
start signal (STF or STR) turns ON (at a stop), online tuning
is performed and a starting delay after start signal turns ON
due to tuning can be avoided.
· Perform offline auto tuning and set "1" (start-time tuning) in
Pr. 95.
· When the start-time tuning completion signal (Y39) is OFF,
start-time tuning with the X28 signal is performed.
· Start-time tuning ends within 500ms maximum.
· When using the X28 signal, set "28" in Pr. 178 to Pr. 189
(input terminal function selection) and assign functions to the
input terminal.
· When using the Y39 signal, set "39 (positive logic) or 139
(negative logic)" in Pr. 190 to Pr. 196 (output terminal function
selection) and assign functions to the output terminal.
While the X28 signal is OFF
Tuning is performed at start when X28 signal is OFF
ON
(even when Y39 is ON).
X28 Signal
OFF
Tune
Tune
Tuning status
Completed
at starting
ON
Y39 signal
OFF
OFF
Start signal
Output frequency
0Hz
Switching motor
Motor
First motor
switching
RT signal
ON
OFF
X28 signal
Tune
Completed
Tuning status
at starting
ON
OFF
Y39 signal
ON
Start
OFF
signal
Output
frequency
0Hz
Tune
Completed Completed
Secondary magnetic Secondary magnetic
flux exists a few seconds flux exists a few seconds
Second motor
First motor
Y39 turns OFF when the
driven motor is switched
ON
to the second motor
Y39 turns ON due
Secondary magnetic
to the residual second
flux exists a few seconds
magnetic flux at the
first motor.
Time
4
Time
201