MITSUBISHI ELECTRIC Mitsubishi Programmable Logic Controller QD75D - Manual (Page 403)

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MELSEC-Q
9 MAJOR POSITIONING CONTROL
POINTS
•
The machine recognizes the presence of a command speed change request when the data is
written to " Cd.25 Position-speed switching control speed change register" with the sequence
program.
• The new command speed is validated after execution of the position-speed switching control before
the input of the position-speed switching signal.
•
The command speed change can be enabled/disabled with the interlock function in speed control
using the "position-speed switching latch flag" ( Md.31 Status: b5) of the axis monitor area.
Restrictions
(1) An axis error (error code: 516) will occur and the operation cannot start if
"continuous positioning control" or "continuous path control" is set in
" Da.1 Operation pattern".
(2) "Position-speed switching control" cannot be set in " Da.2 Control system" of
the positioning data when "continuous path control" has been set in
" Da.1 Operation pattern" of the immediately prior positioning data. (For
example, if the operation pattern of positioning data No. 1 is "continuous path
control", "position-speed switching control" cannot be set in positioning data
No. 2.) An axis error (error code: 516) will occur and the machine will carry
out a deceleration stop if this type of setting is carried out.
(3) The software stroke limit range is only checked during speed control if the "1:
Update current feed value" is set in " Pr.21 Current feed value during speed
control".
The software stroke limit range is not checked when the control unit is set to
"degree".
(4) An error (error code: 507 or 508) will occur and the operation cannot start if
the start point address or end point address for position control exceeds the
software stroke limit range.
(5) Deceleration stop will be carried out if the position-speed switching signal is
not input before the machine is moved by a specified movement amount.
When the position-speed switching signal is input during automatic
deceleration by positioning control, acceleration is carried out again to the
command speed to continue speed control.
When the position-speed switching signal is input during deceleration to a stop
with the stop signal, the control is switched to the speed control to stop the
machine.
Restart is carried out by speed control using the restart command.
(6) A warning (warning code: 501) will occur and control is continued by
" Pr.8 Speed limit value" if a new speed exceeds " Pr.8 Speed limit value" at
the time of change of the command speed.
(7) If the value set in " Da.6 Positioning address/movement amount" is negative,
an error (error code: 530) will occur.