Mitsubishi Electric 800 Series, Instruction Manual, Page: 446 / 727

(C) Motor constant parameters
PARAMETERS
445
5
GROUP
C
 Online auto tuning at startup using the external terminal (setting value
"1", X28 signal and Y39 signal)
• Before turning ON the start signal (STF or STR), online auto tuning
can be performed by turning ON the Start-time tuning start external
input (X28) signal in a stopped status. Such operation will minimize
the startup delay by turning at start.
• Perform offline auto tuning and set Pr.95 = "1" (tuning at start).
• When Start time tuning completion (Y39) is OFF, tuning at start can
be performed with X28 signal.
• Up to 500 ms can be taken to complete tuning at startup.
• To use the X28 signal, set "28" in any of
Pr.178 to Pr.189 (Input
terminal function selection) to assign the function to an input
terminal.
• To use the Y39 signal, set "39 (positive logic) or 139 (negative logic)"
in any of Pr.190 to Pr.196 (Output terminal function selection) to
assign function to an output terminal.
Time
X28 signal
Tuning status
at starting
Y39 signal
Start signal
Tune
Completed
ON
(Hz)
Output frequency
X28 Signal
Tuning status
at starting
Y39 signal
Start signal
Output
frequency
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
OFF
ON
Tune
Completed
Completed
ON
Tune
Completed Completed
ON
Secondary magnetic
flux exists a few seconds
Secondary magnetic
flux exists a few seconds
Secondary magnetic
flux exists
Secondary magnetic
flux exists
a few seconds
Secondary magnetic
flux exists a few seconds
ON
0Hz
0Hz
ON
Tune
ON
Tune
ON
Tune
ON
ON
Tune
Completed Completed
Tune
Completed
Completed
ON
ON
Tune
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.
Tuning is not
performed if the
Y39 signal is ON.
Tuning is performed at start when X28 signal is OFF
(even when Y39 is ON).
Tuning is not performed at start since X28 signal
and Y39 signal is ON.
Time
Time
X28 Signal
Tuning status
at starting
Y39 signal
Start signal
Output frequency
X28 Signal
Tuning status
at starting
Y39 signal
Start signal
Switching motor
Start
signal
Output
frequency
OFF
0Hz
Time
Y39 signal
OFF
OFF
ON
X28 signal
Tuning status
at starting
Motor
switching
RT signal
ON
First motor
Second motor
First motor
ON
Y39 turns OFF when the
driven motor is switched
to the second motor
Y39 turns ON due
to the residual second
magnetic flux at the
first motor.
ON a few seconds
While the X28 signal is OFF While the motor is stopped
While the X28 signal is ON