Mitsubishi Electric MELSEC-L LD75D, User Manual

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CHAPTER 9 MAJOR POSITIONING CONTROL
9
9.
2 Set
ting t
he Pos
itioning
D
at
a
(2) 2-axis circular interpolation control with sub point designation (INC circular
sub)
(a) Operation chart
In the incremental system, 2-axis circular interpolation control with sub point designation, positioning is carried
out from the current stop position (start point address) to a position at the end of the movement amount set in "
Da.6 Positioning address/movement amount" in an arc path that passes through the sub point address set in "
Da.7 Arc address". The movement direction is determined by the sign of the movement amount.
The resulting control path is an arc having as its center the intersection point of perpendicular bisectors of the
straight line between the start point address (current stop position) and sub point address (arc address)
calculated from the movement amount to the sub point, and a straight line between the sub point address (arc
address) and end point address (positioning address) calculated from the movement amount to the end point.
(b) Restrictions
2-axis circular interpolation control cannot be set in the following cases.
• When "degree" is set in "[Pr.1] Unit setting"
• When the units set in "[Pr.1] Unit setting" are different for the reference axis and interpolation axis. ("mm"
and "inch" combinations are possible.)
• When "reference axis speed" is set in "[Pr.20] Interpolation speed designation method"
An error will occur and the positioning will not start in the following cases. The machine will immediately stop if
the error is detected during positioning control.
• When the radius exceeds "536870912 (=2
29
)". (The maximum radius for which circular interpolation
control is possible is "536870912 (=2
29
)"

An error "Outside radius range" (error code: 544) will occur at
positioning start.
• When the auxiliary point address is outside the range of -2147483648 (-2
31
) to 2147483647 (2
31
-1): An
error 525 will occur.
• When the end point address is outside the range of -2147483648 (-2
31
) to 2147483647 (2
31
-1): An error
526 will occur.
• When the auxiliary point address, center point address is outside the range of "-2147483648 (-2
31
) to
2147483647 (2
31
-1)": The error "Sub point setting error" (error code: 525) will occur at a positioning start.
• When the start point address is the same as the end point address

The error "End point setting error"
(error code: 526) will occur.
Reverse direction
Reverse direction
Forward direction
Movement by circular interpolation
Forward direction
Movement amount to the end point
Movement
amount to the
sub point
Movement amount
to sub point
Movement amount
to the end point
Arc center
Sub point address
(arc address)
Start point
address