Circle With Tangential Transition: Ct - Siemens SINUMERIK 808D ADVANCED Programming And Operating Manual

See the following illustration for circle with end point and intermediate point specification using the example of G90:
Programming example
N5 G90 X30 Y40
N10 CIP X50 Y40 I1=40 J1=45
8.4.3

Circle with tangential transition: CT

Functionality
With CT and the programmed end point in the current plane G17 through G19, a circle is generated which is connected
tangentially to the previous path segment (circle or straight line) in this plane.
This defines the radius and center point of the circle from the geometric relationships of the previous path section and the
programmed circle end point.
See the following illustration for circle with tangential transition to the previous path section:
Programming example
N10 G1 X20 F300
N20 CT X... Y...
Programming and Operating Manual (Milling)
6FC5398-4DP10-0BA1, 01/2014
;Starting point circle for N10
; End point and intermediate point
; Straight line
; Circle with tangential connection
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