Siemens SINAMICS S120 Function Manual page 499

parameterized position, speed, acceleration override and delay override, the required clamping
torque can be specified as task parameter p2622. From the start position onwards, the target
position is approached with the parameterized speed. The fixed stop (the workpiece) must be
between the start position and the braking point of the axis; that is, the target position is placed
inside the workpiece.
The preset torque limit is effective from the start, i.e. travel to fixed stop also occurs with a
reduced torque. The preset acceleration and delay overrides and the current speed override
are also effective. Dynamic following error monitoring (p2546) in the position controller is not
effective when traveling to the fixed stop. As long as the drive travels to the fixed stop or is in
fixed stop, the "Travel to fixed stop active" status bit r2683.14 is set.
Fixed stop is reached
As soon as the axis comes into contact with the mechanical fixed stop, the closed-loop control
in the drive raises the torque so that the axis can move on. The torque increases up to the value
specified in the task and then remains constant. The status bit r2683.12 "Fixed stop reached"
is set depending on the binector input p2637 (Fixed stop reached):
● If the following error exceeds the value set in parameter p2634 (fixed stop: maximum
following error) (p2637 = r2526.4) or
● If the status is set externally via the signal at binector input p2637 (fixed stop reached) (for
p2637 ≠ r2526.4)
In travel to fixed stop, the clamping torque or clamping force in the traversing block is configured
via the task parameter. It is specified in the units 0.01 Nm or 1 N (rotary / linear motor). The
function module is coupled to the torque limit of the basic system via the connector output
r2686[0] (torque limit upper) or r2686[1] (torque limit lower), which are connected to the
connector input p1528 (torque limit upper scaling) or p1529 (torque limit lower scaling).
The connector outputs r2686[0] (torque limit upper) and r2686[1] (torque limit lower) are set to
100% when fixed stop is not active. During active fixed stop, r2686[0] (torque limit upper) or
r2686[1] (torque limit lower) are evaluated as a percentage of p1522/p1523 in such a way that
the specified clamping torque or clamping force is limited.
When the fixed stop is acknowledged (p2637), the "Speed setpoint total" (r2562) is recorded,
as long as the binector input p2553 (fixed stop reached message) is set. The speed control
holds the setpoint torque due to the applied speed setpoint. The setpoint torque is output for
diagnosis via the connector output r2687 (torque setpoint).
If the parameterized clamping torque is reached at the fixed stop, the status bit r2683.13 "Fixed
stop clamping torque reached" is set.
Once the "Fixed stop reached" status has been detected, the traversing task "Travel to fixed
stop" is ended. The program advances to the next block depending on the task
parameterization. The drive remains in fixed stop until the next positioning task is processed or
the system is switched to jog mode. The clamping torque is therefore also applied during
subsequent waiting tasks. The continuation condition CONTINUE_EXTERNAL_WAIT can be
used to specify that the drive must remain at the fixed stop until a step enabling signal is applied
externally.
Drive functions
Function Manual, 06/2019, 6SL3097-5AB00-0BP2
Function modules
9.8 Basic positioner
497