Siemens SINUMERIK 840Di Function Manual page 347

2.2 Travel to fixed stop with analog drives
2.2
2.2.1 SIMODRIVE 611 digital (VSA/HSA)
Selection
The NC detects that the function "travel to fixed stop" is selected via the command
FXS[x]=1 and signals the PLC via the IS "Activate travel to fixed stop" (DB31, ... DBX62.4)
that the function has been selected.
If the machine parameter:
MD37050 FIXED_STOP_ACKN_MASK
is set accordingly, then the IS waits for acknowledgment by the PLC in the form of IS
"Activate travel to fixed stop" (DB31, ... DBX3.1)
and then the function is started.
This acknowledgment is not required by the NC for digital drives.
The axis now traverses to the target position at the programmed velocity. At the same time,
the clamping torque (specified via FXST[x]) is transferred to the drive via the digital
interface, and this limits its effective torque. In addition, the acceleration is reduced
accordingly in the NC automatically acc. to FXST[x]).
Fixed stop reached
As soon as the axis reaches the fixed stop, the axial contour deviation increases.
If the recorded threshold in the machine parameter:
MD37030 FIXED_STOP_THRESHOLD
is exceeded or the IS signal "Sensor fixed stop" (DB31, ... DBX1.2) is set, the controller
recognizes that the fixed stop has been reached.
The NC will then delete the distance to go and will synchronize the position setpoint to the
current actual position value. The controller enabling command remains active.
The NC then outputs IS "Fixed stop reached" (DB31 , ... DBX62.5) to the PLC.
If the machine parameter:
MD37060 FIXED_STOP_ACKN_MASK
is set accordingly, then the IS waits for acknowledgment by the PLC in the form of IS
"Acknowledge fixed stop reached" (DB31, ... DBX1.1).
This acknowledgment is not required by the NC for digital drives.
A block change is executed. The clamping torque continues to be applied.
Travel to Fixed Stop (F1)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Detailed Description
2.2 Travel to fixed stop with analog drives
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