Mitsubishi Melsec-Q QD75D1, User Manual

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MELSEC-Q
9 MAJOR POSITIONING CONTROL
(f) In continuous path control, the positioning may be completed before
the set address/movement amount by the distance , and the data
may switch to the "positioning data that will run next".
The value of the distance
is as follows:
• QD75P N/QD75D N:
0 < (Moving distance in 0.9ms at the command speed)
• QD75P /QD75D :
0 < (Moving distance in 1.8ms at the command speed)
Positioning data
No.1
Positioning data
No.2
Positioning data
No.1
Positioning data
No.2
The object reached
the address specified
in Positioning data No.1.
The object reached the
address specified in
Positioning data No.1.
V V
t t
V1
V2
V1
V2
QD75P N/QD75D N: Less than 0.9ms
QD75P /QD75D : Less than 1.8ms
Distance l
QD75P N/QD75D N: 0.9ms or more
QD75P /QD75D :1.8ms or more
Distance l
Acceleration/deceleration (setting) Acceleration/deceleration (actual one)
The distance is output when the next positioning data is running
at the specified speed.
Therefore, the execution time of the next positioning data may be
longer than the set execution time.
*1
If this causes a control problem, take one of the following measures.
1) Use the function "output timing selection of near pass control".
By selecting "At deceleration" as an output timing, the positioning
execution time of the next positioning data remains the same as it
was set. (Refer to Section 12.3.4 "Output timing selection of near
pass control".)
2) Use the "speed change function".
Change speed using the speed change function instead of
continuous path control. (Refer to Section 12.5.1"Speed change
function".)
1: When the command speed V1 of a positioning data and the command
speed V2 of the next positioning data is different significantly, and
V1 > V2
For positioning data in which automatic deceleration is set, the
positioning is completed at the set address. Therefore, in continuous
path control, the address where a positioning is completed may be
different from the set address. However, the address will be the
specified one on completion of automatic deceleration for continuous
positioning control (01) or positioning complete (00).
POINT
In the continuous path control, a speed variation will not occur using the near-pass
function when the positioning data No. is switched (Refer to Section 12.3.3 "Near-
pass function").