Siemens SINUMERIK 840Di Function Manual page 329

Monitoring window
If no torque was programmed in the block or since the beginning of program, the value
entered in the axis specific machine parmeter:
MD37010 FIXED_STOP_TORQUE_DEF
(default setting for clamping torque)
applies.
If the axis leaves the position it was in when the fixed stop was detected, then alarm 20093
"Fixed stop monitoring has responded" is displayed and the "Travel to fixed stop" function
deselected.
The window must be selected by the user such that the alarm is activated only when the axis
leaves the fixed stop position.
Enabling the fixed stop alarms
The machine parameter:
MD37050 FIXED_STOP_ALARM_MASK
can be used to set the enabling of the fixed stop alarms as follows:
MD 37050 = 0
MD 37050 = 2
MD 37050 = 3
All other permissible values of 7 or less do not suppress any alarms.
Using the parts program command NEWCONF a new setting can be activated.
Fixed stop is not reached
If the programmed end position is reached without the status "fixed stop reached" having
been recognized, the alarm 20091 "fixed stop not reached" is activated, depending on the
status of the machine parameter:
MD37050 FIXED_STOP_ALARM_MASK (enabling fixed stop alarms).
Function abort
If the "Travel to fixed stop" function is aborted owing to a pulse disable command,
cancellation of PLC acknowledgments or a Reset in the approach block, the display or
suppression of alarm 20094 can be controlled via:
MD37050 FIXED_STOP_ALARM_MASK.
Abort without alarm
The PLC can initiate travel to fixed stop without an alarm in the approach block (for example,
when the operator actuates a key) if alarm 20094 is suppressed in machine parameter:
MD37050 FIXED_STOP_ALARM_MASK.
Travel to Fixed Stop (F1)
Function Manual, 08/2005 Edition, 6FC5397-0BP10-0BA0
Fixed stop not reached (suppress Alarm 20091)
Fixed stop not reached (suppress alarm 20091) and fixed stop aborted
(suppress alarm 20094)
Fixed stop aborted (suppress alarm 20094)
Detailed Description
2.1 General functionality
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