7. POSITIONING CONTROL
7
−
76
(b) If the stop occurred during position control, then position control continues
until the positioning reaches the set travel value.
The travel value after the restart is calculated as follows:
====
++++
V
t
OFF
ON
P1
P2
P1 : Travel value before stop
P2 : Travel value after restart
SVST insutruction
VPF/VPR instruction
VPSTART
M3205+20n
Speed/position
switching control
start
Operation speed
CHANGE
signal ON
Restart
Stop
Stop
command
received
Speed
control
Position
control
Position
control
Fig.7.28 Restarting During Speed Control
(3) The speed at restart is the speed stored when the VPF/VPR instruction
occurred.
Therefore, even if a speed change occurred before the stop, control restarts at
the speed set at the time of VPF/VPR instruction execution.
t
V
Set
speed
Speed change
Stop command
Position
control
Speed control
Speed
control
Restart
CHANGE signal ON
Operation speed
Fig.7.29 Restarting After Speed Change
Travel value
after restart
(P2)
Set travel
value (P)
Travel value
be-
fore stop (P1)