Siemens SINAMICS S120, Function Manual

Page: 529 / 1094

Function modules
8.8 Basic positioner
Drive functions
Function Manual, 11/2017, 6SL3097-4AB00-0BP5
529
Example with a measuring gear
Figure 8-19 Measuring gear between the motor and encoder
The diagram shows an application example for using referencing with several zero marks
per revolution with a measuring gear located between the motor/load and encoder.
As a result of the measuring gear, several encoder zero marks appear within one motor/load
revolution. Using the BERO signal, also here, the correct zero mark for referencing can be
selected from the several encoder zero marks.
Preconditions
● The position of the zero mark that has the shortest distance to the position when the
BERO signal switches is to be determined.
● The appropriate mechanical preconditions must be fulfilled when mounting the BERO.
● Preferred mechanical configuration
The BERO signal covers the zero mark, as in this case, the zero mark selection is
independent of the direction of rotation.
● In order to be able to precisely determine the position of the BERO (in relation to the
reference position of the encoder) even at higher speeds, this must be connected to a
fast Control Unit input.