Siemens SINAMICS S120 Function Manual page 260

Function modules
7.9 Basic positioner
● Flying referencing (passive (p2597 = 1))
● Absolute encoder
A connector input is provided for all referencing types to input the reference point coordinate;
this allows, e.g. the change/input via the higher-level control. However, to permanently enter
the reference point coordinate, a setting parameter for this quantity is also required. As
standard, this setting parameter p2599 is interconnected to connector input p2598.
Set reference point
The reference point can be set using a 0/1 edge at binector input p2596 (set reference point)
if no traversing commands are active or they have been interrupted by an intermediate stop
and the actual position value is valid (p2658 = 1 signal). The current actual position of the
drive is set here as the reference point using the coordinates specified by connector input
p2598 (reference point coordinates). The setpoint (r2665) is adjusted accordingly.
This function also uses actual position value correction for the position controller (p2512 and
p2513). Connector input p2598 is connected to setting parameter p2599 as standard. The
binector input is not effective for the traversing task being presently executed.
Absolute encoder adjustment
Absolute encoders must be adjusted while commissioning. After the machine has been
powered-down the position information of the encoder is kept.
When p2507 = 2 is entered, using the reference point coordinate in p2599, an offset value
(p2525) is determined. This is used to calculate the position actual value (r2521). Parameter
p2507 signals the adjustment with a "3" - in addition bit r2684.11 (reference point set) is set
to "1".
The offset of the encoder adjustment (p2525) should be saved in a non-volatile fashion
(RAM to ROM) to permanently save it.
Note
If an adjustment is lost on an already adjusted axis, the axis will remain unadjusted from
CU320 with order number 6SL3040-...-0AA1 and version C or higher or CU310 even when
the drive unit is switched OFF/ON. The axis needs to be adjusted again in such cases.
260
– Absolute encoder adjustment
– Flying referencing (passive (p2597 = 1))
Function Manual, (FH1), 07/2007 Edition, 6SL3097-2AB00-0BP4
Drive Functions