5.5 Retracing During Positioning - Mitsubishi Electric A173UHCPU Programming Manual

5. SEQUENCE PROGRAMS AND SFC PROGRAMS

5.5 Retracing during Positioning

Control mode
ABS-1
Linear control
INC-1
Circular interpolation
ABS Circular
control
Fixed-pitch feed control FEED-1
CPSTART1
Constant-speed control
CPSTART3
Speed control (I)
VF
Speed control (II) VVF
Speed/position control
VPF
Position follow-up control PFSTART
Speed switching control VSTART
JOG operation
High speed oscillation OSC
Zeroing ZERO
(Reference) Minor error 301 : Speed has been changed during zeroing.
Minor error 305 : The designated speed is not within the range from 0 to the speed limit value.
Minor error 310 : Speed has been changed during high speed oscillation.
[Control Details]
When a minus speed is designated in the CHGV instruction at the start to make a
speed change request, deceleration begins at that time and retracing starts on
completion of deceleration. The following operations can be performed by the
servo instructions.
Servo instruction
ABS-2 ABS-3 ABS-4
INC-2 INC-3 INC-4
INC Circular
FEED-2 FEED-3
CPSTART2
CPSTART4
VR
VVR
VPR VPSTART
(1) When speed is changed to minus speed, control takes place as shown in the
table above according to the control mode in use.
(2) The designated retracing speed is indicated by the absolute value of the
change speed. When it exceeds a speed limit value, a minor error 305 is
returned and retracing is controlled according to the speed limit value.
(3) When stopping (waiting) continues at a return position, processing takes place
as follows.
(a) Signal status
• Start accept (M2001+n)
• Positioning start completion (M2400 + 20n)
• Positioning completion (M2401+20n)
• In-position (M2402+20n)
• Command in-position (M2403+20n)
• Speed change "0" accept flag (M2240+n)
(b) When attempting a start again, change the speed to plus speed.
(c) When terminating positioning, set the stop command to ON.
(d) When attempting a minus speed change again, it is ignored.
(4) Retracing takes place in the speed control mode as follows.
(a) When changing the travel direction again, change the speed to plus speed.
(b) When stopping retracing, set the stop command to ON.
(c) When making minus speed change again, speed change is made in the
reverse direction.
The travel direction is reversed on completion of deceleration, and retracing takes
place and stops (waits) at the positioning start point according to the absolute value
of the designated speed. In circular interpolation, retracing takes place on the
circular track.
The travel direction is reversed on completion of deceleration, and retracing takes
place and stops (waits) at the preceding point according to the absolute value of the
designated speed.
The travel direction is reversed on completion of deceleration according to the
absolute value of the designated speed. Retracing does not stop unless the stop
command is entered.
Retracing is not possible.
A normal speed change request is assumed.
A minor error 305 is returned and a speed limit value is used for control.
Speed cannot be changed. A minor error 310 is returned.
Speed cannot be changed. A minor error 301 is returned.
5 − 11
Operation
ON (remains in the status
before CHGV execution)
ON (remains in the status
before CHGV execution)
OFF
ON
OFF
ON