Siemens SIMATIC S7-1500 Function Manual page 44

Basics
3.14 Homing
Example of homing in the negative direction
The move to the homing mark occurs in the negative direction by means of a direction
reversal during the homing process. The move to the home position causes another direction
reversal and occurs in the positive direction.
The following figure shows the homing motion with the following settings:
● Active homing with zero mark and proximity switch
● Approach in the positive direction
● Homing in the negative direction
● Positive home position offset
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S7-1500 Motion Control V13 Update 3
Function Manual, 07/2014, A5E03879256-AC