Indexed Actual Value Acquisition - Siemens SINAMICS S120 Function Manual

A correction can be made using connector input p2513 (correction value, actual position
value processing) and a positive edge at binector input p2512 (activates the correction
value). When the "basic positioning" function module is activated, p2513 is automatically
interconnected with r2685 (EPOS correction value) and p2512 with r2684.7 (activate
correction). This interconnection enables modulo offset by EPOS, for example.
The correction value present at the connector input p2513 can be negated and activated via
p2730.
p2516 can be used to switch in position offset. Using EPOS, p2516 is automatically
interconnected to r2667. Backlash compensation is implemented using this interconnection.
Using the connector input p2515 (position setting value) and a "1" signal at binector input
p2514 (set actual position value), a position setting value can be entered.
NOTICE
No evaluation of the incoming encoder increments
When the actual position value is set (p2514 = "1" signal), the actual position value of the
position controller is kept at the value of connector p2515 as standard.
Incoming encoder increments are not evaluated. A difference in position cannot be
compensated for in this situation.
An inversion of the actual position value resulting from the encoder is undertaken using
parameter p0410. An inversion of the axis motion can be entered using a negative value in
p2505.
8.7.2.3

Indexed actual value acquisition

The indexed actual position value acquisition permits, e.g. length measurements on parts as
well as the detection of axis positions by a higher-level controller (e.g. SIMATIC S7) in
addition to the position control, e.g. of a belt conveyor.
Two more encoders can be operated in parallel with the encoders for actual value
preprocessing and position control in order to collect actual values and measured data.
The indexed acquisition of actual values can preprocess an actual position value at each of
the three encoder outputs. The parameter p2502[0...3] is used to select the encoder
evaluation for position control.
The parameters of the indexed actual value acquisition are indexed four times. The indexes
1..3 are assigned to the encoder evaluations 1..3. The index 0 is assigned to position control.
The parameter r2521[0...3] can be used to retrieve the current actual values of all connected
encoders. For example, the actual position value for position control in r2521[0] is identical
with the value r2521[1] if the position control uses encoder evaluation 1. The signal source
for a position offset can be set in parameter p2516[0...3].
The absolute encoder adjustment is initiated via p2507[0...3] = 2, and its successful
completion is reported via p2507[0...3] = 3. The signal source "Reference point coordinate
for the position controller" p2598[0] is interconnected with p2599 during basic positioning.
The other signal sources are not interconnected in the standard configuration.
Drive functions
Function Manual, (FH1), 04/2014, 6SL3097-4AB00-0BP4
Function modules
8.7 Closed-loop position control
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