Siemens SIMOTION C 230-2 Operating Instructions Manual page 27

Absolute encoder (SSI, C230-2, C240)
Instead of conventional incremental encoders, which supply only a relative dimension for the
distance traveled, absolute encoders with a serial interface can be connected. No homing
operation need be performed for these encoders as they always supply the absolute position as
an actual value.
A one-time adjustment is required for an axis with an absolute encoder when the machine is
initially commissioned.
Encoder emulation (C230-2, C240)
Modern motor/converter systems often have a high-resolution motor measuring system (rotor
position encoder) connected at the converter. Here the converter provides the position
information via an interface that emulates an incremental encoder (e.g. incremental shaft
encoder (WSG) interface with SIMODRIVE). A separate position measuring system is not
required in this case.
Figure 2-5
SIMOTION C
Operating Instructions, 11/2022, A5E33441428B
Servo system with converter, e.g. SIMODRIVE 611 universal, with incremental encoder
2.3 The fundamentals of motion control
Description
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