Mitsubishi Melsec-Q QD75D1, User Manual

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MELSEC-Q
9 MAJOR POSITIONING CONTROL
POINT
•
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
QD75 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.
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
2.5 m 2.5 m
INC line1
Fixed-feed 1
2 pulses
3 pulses (=2.5+0.5)
2 pulses
2 pulses
Movement
amount
Output pulses
0.5 pulse hold by the QD75 is
carried to next positioning.
0.5 pulse hold by the QD75 is cleared to 0 at start
and not carried to next positioning.
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.
Setting item Setting example Setting details
Da.1 Operation pattern
Positioning
complete
Set "Positioning complete" assuming 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
μ
m
Set the positioning address. (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 to the positioning address.
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.
Axis 1 Positioning data N
o. 1
Da.10 M code 10
Set this when other sub operation commands are issued in
combination with the No. 1 positioning data.
* Refer to Section 5.3 "List of positioning data" for information on the setting details.