9 Positioning Control
9.11 Circular Interpolation Operation
184
FX
3U
-20SSC-H Positioning Block User's Manual
*1.
Shaded columns are invalid in interpolation operation.
*2.
In interpolation operation, the system performs trapezoidal acceleration/deceleration even if
approximate S-shaped acceleration/deceleration is selected.
*3.
For cautions on setting the pulse rate and feed rate in interpolation operation, refer to the following.
→
Refer to Subsection 7.11.3
Note
• The radius is specified as r. When r is a positive value, the small circle (a) path is selected and when it is
negative, the big circle (b) path is selected.
• Pulse rate and feed rate
During the circular interpolation operation, the radius value is kept constant and pulses are allocated to the
X and Y axes. If the ratio of the pulse rate to the feed rate differs between the X-axis and Y-axis, the circle
becomes deformed. Set the interpolation gear ratio selection function in the X- axis, Y-axis when the ratio
differs between the X-axis and the Y-axis if the version is Ver.1.20 or later.
→
For details on the interpolation gear ratio selection, refer to Subsection 7.11.3
• Use the center coordinate specification in a perfect circle operation.
• During continuous pass operation
If the circular path is too short and the travel time from the start point to the target point is shorter than the
interpolation time constant, the operation temporarily stops, and shifts to the next interpolation operation.
• When interpolation operations are consecutively repeated in a table operation, the 20SSC-H provides
continuous pass operation.
→
For details on the continuous pass operation, refer to Section 10.10
2. Operation information
Set a circular interpolation operation ("radius, CW direction" or "radius, CCW direction") and an absolute/
relative address in the operation information.
→
For details, refer to Chapter 10
BFM Number
Data type
X-axis
Y-axis
Current address (pulse)
BFM #3,#2
BFM #103,#102
Monitor data
Real current address (user) (Ver.1.20 or later)
BFM #21,#20
BFM #121,#120
Monitor data
Real current address (pulse) (Ver.1.20 or later)
BFM #23,#22
BFM #123,#122
Monitor data
Operation speed present value
BFM #11,#10
BFM #111,#110
*1
Monitor data
System of units (user unit)
Operation parameter 1
BFM #14000 b1,b0
BFM #14200 b1,b0
Positioning parameters
Unit of measurement for the
user units
Operation parameter 1
BFM #14000 b3,b2
BFM #14200 b3,b2
Positioning parameters
Position data magnification
Operation parameter 1
BFM #14000 b5,b4
BFM #14200 b5,b4
Positioning parameters
Acceleration/deceleration
mode
*2
Operation parameter 1
BFM #14000 b11
BFM #14200 b11
Positioning parameters
STOP mode
Operation parameter 1
BFM #14000 b15
BFM #14200 b15
Positioning parameters
Servo end check enabled/
disabled
Operation parameter 2
BFM #14002 b0
BFM #14202 b0
Positioning parameters
Servo ready check enabled/
disabled
Operation parameter 2
BFM #14002 b1
BFM #14202 b1
Positioning parameters
Interpolation gear ratio
selection
*3
(Ver.1.20 or later)
Operation parameter 2
BFM #14002 b14
Positioning parameters
Pulse rate
*3
BFM #14005,#14004 BFM #14205,#14204 Positioning parameters
Feed rate
*3
BFM #14007,#14006 BFM #14207,#14206 Positioning parameters
Maximum speed
BFM #14009,#14008 BFM #14209,#14208 Positioning parameters
Interpolation time constant
BFM #14022
BFM #14222
Positioning parameters
Servo end evaluation time
BFM #14032
BFM #14232
Positioning parameters
Positioning completion signal output waiting time
(Ver.1.20 or later)
BFM #14106
BFM #14306
Positioning parameters