MITSUBISHI ELECTRIC Mitsubishi Programmable Logic Controller QD75D - Manual (Page 249)

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MELSEC-Q
6 SEQUENCE PROGRAM USED FOR POSITIONING CONTROL
[1] Starting by inputting positioning start signal
Operation when starting
(1) When the positioning start signal turns ON, the start complete signal and
BUSY signal turn ON, and the positioning operation starts.
It can be seen that the axis is operating when the BUSY signal is ON.
(2) When the positioning start signal turns OFF, the start complete signal also
turns OFF.
If the positioning start signal is ON even after positioning is completed, the
start complete signal will remain ON.
(3) If the positioning start signal turns ON again while the BUSY signal is ON, the
warning "operating start (warning code: 100)" will occur.
(4) The process taken when positioning is completed will differ according to case
(a) and (b) below.
(a) When next positioning is not to be carried out
• If a dwell time is set, the system will wait for the set time to pass, and then
positioning will be completed.
•
When positioning is completed, the BUSY signal will turn OFF and the
positioning complete signal will turn ON. However, when using speed
control or when the positioning complete signal ON time is "0", the signal
will not turn ON.
•
When the positioning complete signal ON time is passed, the positioning
complete signal will turn OFF.
(b) When next positioning is to be carried out
• If a dwell time is set, the system will wait for the set time to pass.
•
When the set dwell time is passed, the next positioning will start.
t
Positioning start signal
[Y10, Y11, Y12, Y13] OFF
ON
Start complete signal
[X10, X11, X12, X13] OFF
ON
OFF
ON
OFF
ON
Positioning
V
Dwell time
BUSY signal
[XC, XD, XE, XF]
Positioning complete
signal
[X14, X15, X16, X17]
Fig. 6.3 ON/OFF timing of each signal at start of positioning
POINTS
The BUSY signal [XC, XD, XE, XF] turns ON even when position control of movement amount 0 is
executed. However, since the ON time is short, the ON status may not be detected in the sequence
program.
(The ON status of the start complete signal [X10, X11, X12, X13], positioning complete signal [X14,
X15, X16, X17] and M code ON signal [X4, X5, X6, X7] can be detected in the sequence program.)