Mitsubishi Electric MELSEC-L LD75D, User Manual

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CHAPTER 8 OPR CONTROL
8
8.
2 Mac
hine
O
P
R
8.2.2
Machine OPR method
The method by which the machine OP is established (method for judging the OP position and machine OPR
completion) is designated in the machine OPR according to the configuration and application of the positioning
method.
The following table shows the six methods that can be used for this OPR method. (The OPR method is one of the
items set in the OPR parameters. It is set in "[Pr.43] OPR method" of the basic parameters for OPR.)
*1 The following are the signals input as the zero signals of the LD75 in the corresponding OPR methods.
The following shows the external I/O signals used for machine OPR.

: Necessary,

: Necessary as required,

: Unnecessary
[Pr.43] OPR method Operation details
Near-point dog method
Deceleration starts by the OFF

ON of the near-point dog. (Speed is reduced to "[Pr.47] Creep speed".)
The operation stops at the first zero signal
*1
after the near-point dog turns from ON

OFF.
When a "deviation counter clear output" is completed, the machine OPR is completed.
Stopper method 1)
The stopper position is regarded as the OP.
After the deceleration starts by the OFF

ON of the near-point dog, the machine presses against the stopper at the
"[Pr.47] Creep speed" and stops.
The machine OPR is regarded as completed on completion of the deviation counter clear output provided after "[Pr.49]
OPR dwell time" passed after stoppage.
Stopper method 2)
The stopper position is regarded as the OP.
After the deceleration starts by the OFF

ON of the near-point dog, the machine presses against the stopper at the
"[Pr.47] Creep speed" and stops.
The machine OPR is regarded as completed on completion of the deviation counter clear output provided after the zero
signal
*1
is detected after stoppage.
Stopper method 3)
The stopper position is regarded as the OP.
The machine starts at the "[Pr.47] Creep speed" from the beginning, then presses against the stopper at the "[Pr.47]
Creep speed" and stops.
The machine OPR is regarded as completed on completion of the deviation counter clear output provided after the zero
signal
*1
is detected after stoppage.
Count method 1)
The deceleration starts by the OFF

ON of the near-point dog, and the machine moves at the "[Pr.47] Creep speed".
The machine stops at the zero signal
*1
after moving the distance set in the "[Pr.50] Setting for the movement amount after
near-point dog ON" from the near point dog OFF

ON position. When a "deviation counter clear signal output" is
completed, the machine OPR is regarded as completed.
Count method 2)
The deceleration starts by the OFF

ON of the near-point dog, and the machine moves at the "[Pr.47] Creep speed".
The machine moves the distance set in the "[Pr.50] Setting for the movement amount after near-point dog ON" from the
near point dog OFF

ON position, and stops at that position. The machine OPR is then regarded as completed.
• Near-point dog method, count method 1)
Signal that is output as a single pulse at one motor revolution (e.g. Z-phase signal output from the drive unit)
• Stopper method 2), 3)
Signal that is output on detection of contact with the stopper (Input externally)
[Pr.43] OPR method
Signal required for control
Torque limit
Near-point dog Zero signal
Upper/lower limit
switches
Deviation counter
clear output
Near-point dog method
    
Stopper method 1)     
Stopper method 2)
    
Stopper method 3)
    
Count method 1)
    
Count method 2)     