Fundamentals, file management
3.1
Fundamentals
3
124
HEIDENHAIN | TNC 620 | ISO Programming User's Manual | 9/2016
Absolute and incremental workpiece positions
Absolute workpiece positions
Absolute coordinates are position coordinates that are referenced
to the datum of the coordinate system (origin). Each position on the
workpiece is unambiguously defined by its absolute coordinates.
Example 1: Holes dimensioned in absolute coordinates
Hole
1
Hole
2
Hole
3
X = 10 mm
X = 30 mm
X = 50 mm
Y = 10 mm
Y = 20 mm
Y = 30 mm
Incremental workpiece positions
Incremental coordinates are referenced to the last programmed
nominal position of the tool, which serves as the relative
(imaginary) datum. When you write an NC program in incremental
coordinates, you thus program the tool to move by the distance
between the previous and the subsequent nominal positions. This
is why they are also referred to as chain dimensions.
To program a position in incremental coordinates, enter the
function G91 before the axis.
Example 2: Holes dimensioned in incremental coordinates
Absolute coordinates of hole
4
X = 10 mm
Y = 10 mm
Hole
5
, with respect to
4
Hole
6
, with respect to
5
G91 X = 20 mm
G91 X = 20 mm
G91 Y = 10 mm
G91 Y = 10 mm
Absolute and incremental polar coordinates
Absolute coordinates always refer to the pole and the angle
reference axis.
Incremental polar coordinates always refer to the last programmed
nominal position of the tool.
Summary of Contents for TNC 620 Programming Station
Page 4: ......
Page 5: ...Fundamentals ...
Page 28: ...Contents 28 HEIDENHAIN TNC 620 ISO Programming User s Manual 9 2016 ...
Page 57: ...1 First Steps with the TNC 620 ...
Page 77: ...2 Introduction ...
Page 110: ......
Page 111: ...3 Fundamentals file management ...
Page 166: ......
Page 167: ...4 Programming aids ...
Page 194: ......
Page 195: ...5 Tools ...
Page 234: ......
Page 235: ...6 Programming contours ...
Page 284: ......
Page 285: ...7 Data transfer from CAD files ...
Page 304: ......
Page 305: ...8 Subprograms and program section repeats ...
Page 323: ...9 Programming Q parameters ...
Page 384: ......
Page 385: ...10 Miscellaneous functions ...
Page 407: ...11 Special functions ...
Page 433: ...12 Multiple axis machining ...
Page 475: ...13 Pallet management ...
Page 480: ......
Page 481: ...14 Manual Operation and Setup ...
Page 549: ...15 Positioning with Manual Data Input ...
Page 554: ......
Page 555: ...16 Test Run and Program Run ...
Page 590: ......
Page 591: ...17 MOD Functions ...
Page 622: ......
Page 623: ...18 Tables and Overviews ...