Siemens SINAMICS S120 Function Manual page 437

The following diagram illustrates an absolute encoder that can represent eight encoder
revolutions (p0421 = 8).
Figure 7-9
In this example, this means:
● Without position tracking, the position for +/- 4 encoder revolutions about r2521 = 0 LU
● With position tracking, the position for +/- 12 encoder revolutions (+/- 12 load revolutions
Practical example:
For a linear axis, the value for p2721 is set to 262144 for an encoder with p0421 = 4096.
That means, +/- 131072 encoder revolutions or load revolutions can be reproduced in this
way.
For a rotary axis, a value for p2721 = p0421 is set for an encoder.
Configuration of the load gear (p2720).
The following points can be set by configuring this parameter:
● p2720.0: Activation of position tracking
● p2720.1: Setting the axis type (linear axis or rotary axis)
● p2720.2: Reset position
Drive functions
Function Manual, (FH1), 01/2013, 6SL3097-4AB00-0BP3
Position tracking (p2721 = 24), setting p2504 = p2505 =1 (gear factor = 1)
can be reproduced.
with load gear) can be reproduced (p2721 = 24).
Here, a rotary axis refers to a modulo axis; the modulo offset can be activated from a
higher-level controller or EPOS. With a linear axis, position tracking is mainly used to
extend the position area (see section: Virtual multiturn encoder (p2721).
The position values stored in non-volatile memory are reset in response to the following
events:
– When encoder replacement is detected.
– When the configuration of the encoder data set (EDS) is modified.
– When the absolute encoder is adjusted again.
Function modules
7.7 Closed-loop position control
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