Siemens SINUMERIK 840Di Function Manual page 339

Changing the clamping torque using the ramp and values greater than 100%
A clamping torque change is transferred to the drive steplike. It is possible to specify a ramp
for always reaching a changed torque limit via the machine parameter:
MD37012 FIXED_STOP_TORQUE_RAMP_TIME.
Clamping torque greater than 100%
Values greater than 100% for the setting data:
SD43510 FIXED_STOP_TORQUE
are only practical for a short time.
Irrespectively, the maximum torque is limited by the drive.
The drive machine dates have a limiting effect, i.e.:
MD1103 Motor current
MD1104 Maximum motor current
MD1105 Reduction in max. motor current
MD1230/1231 Torque limiting value 1/2
For further information, please refer to the Planning Guide SIMODRIVE ThreePhase Motors
for Feed and Main Spindle Drives and to the appropriate document regarding the hydraulic
module /FBHLA/.
References:
/FBHLA/ Description of functions HLA-Module
Status query in the parts program
System variable $AA_FXS[x] indicates the status of the "travel to fixed stop" function.
It has the following coding:
$AA_FXS=0
$AA_FXS=1
$AA_FXS=2
$AA_FXS=3
$AA_FXS=4
$AA_FXS=5
Query of the system variable in the parts program initiates a block search stop.
As a result of the status query in the parts program, it is possible, for example, to react to an
erroneous operational sequence of the "Travel to fixed stop" function.
The following example applies:
MD37050 FIXED_STOP_ALARM_MASK = 0
⇒ An alarm is not generated in the error scenario, and a block change therefore takes place
and the error scenario can be evaluated via the system variable.
Travel to Fixed Stop (F1)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Axis not at fixed stop.
Fixed stop has been approached successfully
(axis is within fixed stop monitoring window).
Approach to fixed stop has failed
(axis is not at fixed stop).
Travel to fixed stop activated.
Fixed stop detected.
Travel to fixed stop is deselected.
The deselection is not yet completed.
Detailed Description
2.1 General functionality
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