Cautions For Positioning Operation; Overlapped Specification Of Operation Mode; When The Travel Distance Is Small - Mitsubishi FX3U-20SSC-H User Manual

FX -20SSC-H Positioning Block User's Manual
3U
7.8

Cautions for Positioning Operation

7.8.1

Overlapped specification of operation mode

The positioning operation does not start at START input/command if multiple operation patterns are selected
(with multiple bits turned on) in the parameters for operating patterns.
Likewise, the positioning operation does not start if multiple positioning commands (i.e. forward/reverse JOG
and mechanical zero return commands of operation command 1) are simultaneously ON.
7.8.2

When the travel distance is small

1. 1-speed positioning operation
If the time needed for the travel distance (target address I) is shorter than the acceleration/deceleration time,
the actual operation speed does not reach the command speed (operation speed 1).
Speed
Start
Traveling time < desired acceleration time + desired deceleration time
*1. For the relation between the time for the actual acceleration/deceleration and the specified time for
desired acceleration/deceleration, refer to the following.
2. Interrupt 1-speed positioning operation
If the time needed for the travel distance (target address 1) is shorter than the deceleration time, the pulse
output stops at the target address 1.
If the travel distance is zero, immediate stop occurs when interrupt input INT0 turns ON.
Speed
Trapezoidal control
Start
*1. For the relation between the time for the actual deceleration and the specified time for desired
deceleration, refer to the following.
56
Desired
acceleration
time
Trapezoidal
control
Approximate S-shaped
control
Operation speed I
Desired
deceleration
time
Operation speed 1
*1
Desired
deceleration
*1
time
Target address 1
Interrupt input (INT0)
Traveling time < desired deceleration time
7 Before Starting Positioning Operation
7.8 Cautions for Positioning Operation
Time
*1
→ Refer to Section 7.2
Approximate S-shaped control
The time to stop is slightly earlier because
deceleration under the approximate S-shaped
control is slower than that of trapezoidal control,
while the travel distance is almost the same as
that of trapezoidal control.
Time
*1
→ Refer to Section 7.2