Siemens SINAMICS S120 Function Manual page 500

Function modules
8.8 Basic positioner
Fixed stop is not reached
If the brake application point is reached without the "fixed stop reached" status being
detected, then the fault F07485 "Fixed stop is not reached" is output with fault reaction
OFF1, the torque limit is canceled and the drive cancels the traversing block.
Note
The fault can be changed into an alarm (see Section "Message configuration" in the
SINAMICS S120 Commissioning Manual), which means that the drive program will advance
to the next specified block.
The target point must be sufficiently far inside the workpiece.
Interruption to "Travel to fixed stop"
The "travel to fixed stop" traversing task can be interrupted and continued using the
"intermediate stop" signal at the binector input p2640. The block is canceled using the
binector input signal p2641 "Reject traversing task" or by removing the controller enable. In
all of these cases, the drive is correspondingly braked. Measures are taken to prevent any
risk of damage if the block is canceled when an axis has almost reached the fixed stop
(setpoint already beyond the fixed stop, but still within the threshold for fixed stop detection).
To do this, the setpoint is updated after standstill (position setpoint = actual position value).
As soon as the fixed stop is reached, the drive remains in fixed stop even after cancelation. It
can be moved away from the fixed stop using jog or by selecting a new traversing task.
Note
The fixed stop monitoring window (p2635) is only activated when the drive is at the fixed stop
and remains active until the fixed stop is exited.
Vertical axis
Note
In servo control, a torque limit offset (p1532) can be entered for vertical axes (see also
Section Vertical axis (Page 170)).
With asymmetrical torque limits p1522 and p1523, the self-weight is taken into account for
travel to fixed stop in parameters r2686 and r2687.
If, for example, with a suspended load, p1522 is set to +1000 Nm and p1523 to -200 Nm,
then a net weight of 400 Nm (p1522 - p1523) is assumed. If the clamping torque is now
configured as 400 Nm, then r2686[0] is preset to 80%, r2686[1] to 0% and r2687 to 800 Nm
when travel to fixed stop is activated.
500
Function Manual, (FH1), 04/2014, 6SL3097-4AB00-0BP4
Drive functions