Count Method 2 - Mitsubishi Electric MELSEC iQ-R-RD75P4 User Manual

Count method 2

The following shows an operation overview of Count method 2, one of the OPR methods.
If a machine OPR operation is started using Count method 2 from a point where the near-point dog is on, the machine moves
in the direction reverse to the OPR direction to go back to a point where the near-point dog turns off, and a normal machine
OPR operation is performed.
Count method 2 is useful for a system that cannot use Zero signal. (Note that compared with Count method 1, the variation of
the stop position occurs in the machine OPR.)
As well as Count method 1, the machine OPR operation can be performed using Count method 2 even in the following
situations.
• Where the near-point dog is on
• After the machine OPR is completed
Operation chart
Machine OPR start
(Positioning start signal)
[Y10, Y11, Y12, Y13]
OPR request flag
Md.31 Status: b3
OPR complete flag
Md.31 Status: b4
Md.26
Axis operation status
Movement amount
Md.34 after near-point dog
ON
Md.20 Current feed value
Machine feed value
Md.21
(1) The machine OPR is started.
(The machine starts accelerating according to the setting of [Pr.51] OPR acceleration time selection in the direction specified in [Pr.44] OPR direction, and
moves at the speed set in [Pr.46] OPR speed when the acceleration is completed.)
(2) When the on state of the near-point dog is detected, the machine starts decelerating.
(3) The machine decelerates to the speed set in [Pr.47] Creep speed and moves at the creep speed after that.
(4) When the machine moves for the movement amount set in [Pr.50] Setting for the movement amount after near-point dog ON from the point where the near-
point dog signal on, the RD75 stops outputting pulses and the machine OPR will be completed.
Restrictions
Since an error of approximately 1ms occurs in taking in the on state of the near-point dog, the variation of the stop position
(OP) occurs compared with other OPR methods.
2 OPR CONTROL
54
2.2 Machine OPR
V
Pr.46 OPR speed
(1)
OFF
Near-point dog
ON
OFF
ON
OFF
OFF
Standby OPR
0
Inconsistent
A value of the movement amount is stored.
Inconsistent
Setting for the movement amount
Pr.50
after near-point dog ON
Pr.47 Creep speed
t
(2) (3) (4)
Md.34 Movement amount after
near-point dog ON
Have sufficient distance
from the OP position
ON
to the near-point dog OFF.
ON
Standby
Value of *1
OP address
*1