MITSUBISHI ELECTRIC Mitsubishi Programmable Logic Controller QD75D - Manual (Page 294)

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MELSEC-Q
8 OPR CONTROL
8.2.7 OPR method (5): Count method1)
The following shows an operation outline of the "count method 1)" OPR method.
In the "count method 1)" machine OPR, the following can be performed:
•
Machine OPR on near-point dog ON
•
Second machine OPR after completion of first machine OPR
Operation chart
1)
The machine OPR is started.
(The machine begins the acceleration designated in " Pr.51 OPR acceleration time selection", in the direction
designated in " Pr.44 OPR direction". It then moves at the " Pr.46 OPR speed" when the acceleration is
completed.)
2) The machine begins decelerating when the near-point dog ON is detected.
3) The machine decelerates to the " Pr.47 Creep speed", and subsequently moves at that speed.
4)
On detection of the first zero signal after the axis has traveled the movement amount set in " Pr.50 Setting for the
movement amount after near-point dog ON" after near-point dog ON, the pulse output from the QD75 stops and the
"deviation counter clear output" is output to the drive unit.
(A "deviation counter clear signal output time" is set in Pr.55 .)
5)
After a "deviation counter clear output" is output to the drive unit, the OPR complete flag Md.31 Status: b4) turns from
OFF to ON, and the OPR request flag ( Md.31 Status: b3) turns from ON to OFF.
t
ON
OFF
ON
OFF
OFF
ON
0
V
ON
Pr. 47 Creep speed
Pr. 46 OPR speed
Pr. 50 Setting for the movement amount
after near-point dog ON
Md.34 Movement amount after near-point dog ON
Zero signal
Near-point dog OFF
Leave sufficient distance from the zero point
position to the near-point dog OFF
Machine OPR start
(Positioning start signal)
Standing by In OPR Md.26 Axis operation status
Inconsistent
Value the machine moved is stored OP address
Value of 1.
Deviation counter clear output
Standing by
Inconsistent
OPR request flag
[ Md.31 Status : b3]
OPR complete flag
[ Md.31 Status : b4]
Md.21 Machine feed value
Md.34 Movement amount
after near-point dog ON
Md.20 Current feed value
Pr.55 Deviation counter clear
signal output time
1
Adjust the setting for the movement amount after
near-point dog ON to be as near as possible to
the center of the zero signal HIGH.
If the setting for the movement amount after
near-point dog ON falls within the zero signal,
there may be produced an error of one servomotor
rotation in the machine OPR stop position.
One servomotor rotation
First zero signal after travel of the movement
amount set to " Pr. 50 Setting for the movement
amount after near-point dog ON"
Fig. 8.12 Count method1) machine OPR