Mitsubishi Electric MELSEC-Q QD75M, User Manual

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MELSEC-Q
9 MAJOR POSITIONING CONTROL
POINT
•
The machine recognizes the presence of a movement amount change request when the data is
written to " Cd.23 Speed-position switching control movement amount change register" with the
PLC program.
•
The new movement amount is validated after execution of the speed-position switching control (INC
mode), before the input of the speed-position switching signal.
•
The movement amount change can be enable/disable with the interlock function in position control
using the “speed-position switching latch flag” ( Md.31 Status : b1) 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) "Speed-position 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",
"speed-position 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) An error (error code: 503) will occur if "current speed (-1)" is set in " Da.8
command speed".
(4) The software stroke limit range check during speed control is made only when
the following (a) and (b) are satisfied:
(a) " Pr.21 Current feed value during speed control" is "1: Update current feed
value".
If the movement amount exceeds the software stroke limit range during
speed control in case of the setting of other than "1: Update current feed
value", an error (error code: 507 or 508) will occur as soon as speed control
is changed to position control and the axis will decelerate to a stop.
(b) When " Pr.1 Unit setting" is other than "2: degree"
If the unit is "degree", the software stroke limit range check is not performed.
(5) If the value set in " Da.6 Positioning address/movement amount" is negative,
an error (error code: 530) will occur.
(6) Deceleration processing is carried out from the point where the speed-position
switching signal is input if the position control movement amount set in
" Da.6 Positioning address/movement amount" is smaller than the
deceleration distance from the " Da.8 Command speed".
(7) Turn ON the speed-position switching signal in the speed stabilization region
(constant speed status). A warning (warning code: 508) will occur because of
large deviation in the droop pulse amount if the signal is turned ON during
acceleration.
During use of the servo motor, the actual movement amount after switching of
speed control to position control is the "preset movement droop
pulse amount". If the signal is turned ON during acceleration/deceleration, the
stop position will vary due to large variation of the droop pulse amount. Even
though "
Md.29 Speed-position switching control positioning amount" is the
same, the stop position will change due to a change in droop pulse amount
when "
Da.8 Command speed" is different.