Load Gear Position Tracking - Siemens SINAMICS S120 Function Manual

Function modules
7.8 Closed-loop position control
7.8.2.4

Load gear position tracking

Features
● Configuration via p2720
● Virtual multiturn via p2721
● Tolerance window for monitoring the position at switching on p2722
● Input of the load gear via p2504 and p2505
● Display via r2723
Requirements
● CU320 with Order No. 6SL3040- ....- 0AA1 and Version C or higher or CU310
● Firmware release from FW2.5
● Absolute encoder
Description
Position tracking enables reproduction of the position of the load when gears are used. It can
also be used to extend the position area.
Position tracking for load gear functions in the same way as position tracking for the
measuring gear (see "Position tracking/Measuring gear"). Position tracking is activated via
parameter p2720.0 = 1. The position tracking of the load gear, however, is only relevant for
the motor encoder (encoder 1). The load gear ratio is entered via parameters p2504 and
p2505. Position tracking can be activated with rotary axes (modulo) and linear axes.
Position tracking for the load gear can only be activated once for each motor data set MDS.
The load position actual value in r2723 (must be requested via Gn_STW.13, see chapter
"Control and status words for encoders") comprises the following information:
● Encoder pulses per revolution (p0408)
● Fine resolution per revolution (p0419)
● Virtual number of stored revolutions of a rotary absolute encoder (p2721)
● Load gear ratio (p2504/p2505)
● Measuring gear ratio (p0433/p0432), if p0411.0 = 1
Note
The sum of p0408, p0419 and p2721 is limited to 32 bits.
Example: Absolute encoder can count 8 encoder revolutions (p0421 = 8)
Note
Load gear problems and solutions, see example in chapter Position tracking -> Measuring
gear.
272
Function Manual, (FH1), 10/2008, 6SL3097-2AB00-0BP5
Drive functions