Siemens SIMATIC S7-1500 Function Manual page 158

Configuring
6.7 Configuring the External Encoder technology object
Homing mark via digital input
Digital input, homing mark
In this dialog field, select a digital input which should act as a homing mark (reference cam).
Homing direction
Select the direction in which the homing mark should be approached for homing.
The following options are available:
● Positive
Axis moves in the direction of higher position values.
● Negative
Axis moves in the direction of lower position values.
● Current
Homing mark
Select which switch position of the "digital input" is to be used as homing mark.
When a "digital input" is overshot, two switch edges which are spatially separated from one
another are generated. The selection of the positive or negative side ensures that the
homing mark is always evaluated based on the same mechanical position.
The positive side is the switch position with a greater position value; the negative side is the
switch position with the lesser position value.
The selection of the side is independent of the approach direction, and independent of
whether it causes a rising or falling edge.
Home position
In this field, configure the absolute coordinate of the home position. The home position
configured here is in effect when the Motion Control instruction "MC_Home" is executed with
Mode = 10.
Note
Parameter "MC_Home.Mode"
The "MC_Home.Mode" parameter for S7-1200 Motion Control and S7-1500 Motion Control
has been standardized within the framework of technology version V2.0. This results in a
new assignment of the parameter values for the "MC_Home.Mode" parameter. A
comparison of the "MC_Home.Mode" parameter for technology versions V1.0 and V2.0 is
available in the section Version overview (Page 86).
158
The currently effective approach direction is used for homing.
S7-1500 Motion Control V13 Update 3
Function Manual, 07/2014, A5E03879256-AC