Siemens SINUMERIK 802D sl Programming And Operating Manual page 230

Define
6.1 Turning On and Reference Point Approach
The "Reference point approach" window displays whether the axes are referenced.
Press the arrow keys.
If you select the wrong approach direction, no motion is carried out.
Approach the reference points for each axis one after the other.
Quit the function by switching the mode (MDA, AUTOMATIC or JOG).
Note
"Reference point approach" is only possible in JOG mode.
6-2
Programming and Operating manual, 06/2006, 6FC5398-4CP10-0BA0
Grinding