MITSUBISHI ELECTRIC Mitsubishi Programmable Logic Controller QD75D - Manual (Page 324)

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MELSEC-Q
9 MAJOR POSITIONING CONTROL
POINT
• When the "reference axis speed" is set during interpolation control, set so the
major axis side becomes the reference axis. If the minor axis side is set as the
reference axis, the major axis side speed may exceed the " Pr.8 Speed limit
value".
Limits to interpolation control
There are limits to the interpolation control that can be executed and speed
( Pr.20 Interpolation speed designation method) that can be set, depending on
the " Pr.1 Unit setting" of the reference axis and interpolation axis. (For example,
circular interpolation control cannot be executed if the reference axis and
interpolation axis units differ.)
The following table shows the interpolation control and speed designation limits.
Pr.1 Unit setting 1
" Da.2 Control system"
interpolation control
Pr.20 Interpolation speed
designation method
Reference axis and interpolation
axis units are the same, or a
combination of "mm" and "inch".
3
Reference axis and
interpolation axis units
differ 3
Composite speed Linear 2 (ABS, INC)
Fixed-feed 2
Reference axis speed
Composite speed 2 Circular sub (ABS, INC)
Circular right (ABS, INC)
Circular left (ABS, INC) Reference axis speed
Composite speed Linear 3 (ABS, INC)
Fixed-feed 3
Reference axis speed
Composite speed Linear 4 (ABS, INC)
Fixed-feed 4
Reference axis speed
: Setting possible, : Setting not possible.
1 "mm" and "inch" unit mix possible.
2 "degree" setting not possible. A "Circular interpolation not possible (error code: 535)" will occur and the position
cannot start if circular interpolation control is set when the unit is "degree". The machine will immediately stop if
"degree" is set during positioning control.
3 The unit set in the reference axis will be used for the speed unit during control if the units differ or if "mm" and "inch"
are combined.
Axis operation status during interpolation control
"In interpolation" will be stored in the " Md.26 Axis operation status" during
interpolation control. "Standing by" will be stored when the interpolation operation
is terminated. Both the reference axis and interpolation axis will carry out a
deceleration stop if an error occurs during control, and "error occurring" will be
stored in the operation status.