Siemens SIMATIC S7-300 Manual page 225

9.3.8 Teach in (job no. 19)
Overview
In a program block selected with the program number and block number, the
current actual position is entered as a position setpoint (Caution: This is an
absolute position).
The Teach-in facility is possible only in the following modes:
and while the axis is not in motion, when "Processing in progress" = 0.
The program and the appropriate program block must be present on the
FM 354 (see Parameterization, Chapter 5).
9.3.9 Set reference point (job no. 21)
Overview
You can use this function to synchronize the axis without reference point ap-
proach.
Function With Set Reference Point, a position value at the instantaneous position of
the axis, indicated as a parameter, is accepted as an actual value.
For axes with an absolute encoder, the generated position reference is entered
in MD17. At a known axis position, the known actual position of the system
of measurement is transmitted to the FM 354 with Set Reference Point. This
value is set as the actual value of the axis. At the same time, this position
reference is saved, in that the assignment of the encoder actual value to the
axis reference point is calculated from the assignment of the set actual posi-
tion to the encoder actual value at this point of the axis; it is then entered in
MD17.
FM 354 Servo Drive Positioning Module
Jogging
Incremental Relative
MDI
Description of Functions
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