Siemens SINUMERIK 840C - Manual (Page 343)

6 NC Machine Data (NC MD), NC Setting Data (NC SD) 09.95
6.7 Axis-specific MD 2 (axial data 2)
6.7 Axis-specific MD 2 (axial data 2)
SW prelimit switch 1100*
Default value Lower input limit Upper input limit Units
20 000 - 99 999 999 99 999 999 units (MS)
Active
at once
Defines the distance at which the braking operation is to be prematurely begun if the current
speed exceeds the speed in NC MD 1, thus ensuring that the position of the software limit
switch will be overrun only to a negligible degree during circular interpolation.
Overshooting of the pre-limit switch triggers alarm 3091 except in the case of rapid traverse.
Recommendation
The value entered should be slightly higher than the value which would correspond to the
braking distance from rapid traverse to NC MD 1.
In program mode, travel movements which would result in overshooting of the software limit
switch position are simply not started (alarm 2065 is triggered).
Exception!
Circular interpolation, helical interpolation
Start of deceleration to zero speed
Reduction to NC MD 1
A E
Software limit
switch
Software pre-
limit switch
Machine data for the ”Setup mode division-related” function.
Number of divisions 1104*
Default value Lower input limit Upper input limit Units
0 0 999 –
Active
at once
Input limits: The value 0 is allowed only if the axis involved is not an indexing axis
(NC MD 564* bit 4 = 0).
The number of divisions gives the divisions per division reference dimension (NC MD 1108*).
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SINUMERIK 840C (IA)