Mitsubishi Electric MELSEC-L LD75D, User Manual

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● When the movement amount is converted to the actual number of output pulses, a fraction appears after the decimal
point, according to the movement amount per pulse. This fraction is normally retained in the LD75 and reflected at the
next positioning. For the fixed-feed control, since the movement distance is maintained constant (= the output number of
pulses is maintained constant), the control is carried out after the fractional pulse is cleared to zero at start.
(3) Positioning data setting example
The following table shows setting examples when "1-axis fixed-feed control (fixed-feed 1)" is set in positioning
data No. 1 of axis 1.
Refer to

Page 152, Section 5.3 for information on the setting details.
Setting item Setting example Setting details
Axis 1 positioning
data No. 1
[Da.1] Operation pattern Positioning complete
Set "Positioning complete" assuming that the next positioning data will
not be executed.
[Da.2] Control system Fixed-feed 1 Set 1-axis fixed-feed control.
[Da.3] Acceleration time No. 1
Designate the value set in "[Pr.25] Acceleration time 1" as the
acceleration time at start.
[Da.4] Deceleration time No. 0
Designate the value set in "[Pr.10] Deceleration time 0" as the
deceleration time at deceleration.
[Da.5]
Axis to be
interpolated
 Setting not required. (Setting value will be ignored.)
[Da.6]
Positioning
address/movement
amount
8000.0

m
Set the movement amount. (Assuming "mm" is set in "[Pr.1] Unit
setting".)
[Da.7] Arc address

Setting not required. (Setting value will be ignored.)
[Da.8] Command speed 6000.00mm/min Set the speed during movement.
[Da.9] Dwell time 500ms
Set the time the machine dwells after the positioning stop (pulse output
stop) to the output of the positioning complete signal.
[Da.10] M code 10
Set this when other sub operation commands are issued in
combination with the No. 1 positioning data.
Accumulation/cutoff for fractional pulses
When movement amount per pulse is 1.0 m and movement for 2.5 m is executed two times;
Conversion to output pulses: 2.5[ m] 1.0 = 2.5 pulses
m 5 . 2 m 5 . 2
INC line1
Fixed-feed 1
2 pulses 3 pulses (=2.5+0.5)
2 pulses
2 pulses
Movement
amount
Output pulses
0.5 pulse held by the LD75 is
carried to next positioning.
0.5 pulse held by the LD75 is cleared to 0 at start
and not carried to next positioning.