HEIDENHAIN ND 720 v.3 - Manual (Page 7)

7
Nominal position, actual position and distance-to-go
The position to which the tool is to move is called the nominal
position (
S ). The position at which the tool is actually located at any
given moment is called the actual position ( I ).
The distance from the nominal position to the actual position is called
the distance-to-go (
R
).
Sign for distance-to-go
When you are using the distance-to-go display, the nominal position
becomes the relative datum (display value 0). The distance-to-go is
therefore negative when the tool moves in the positive axis direction,
and positive when it moves in the negative axis direction.
Fundamentals
Y
X
Z
I
S
R
Bateil1.pm6 07.11.2001, 10:36 7