Siemens SINUMERIK 840C Installation Instructions Manual page 225

6 NC Machine Data (NC MD), NC Setting Data (NC SD)
6.4 Axis-specific MD 1 (axial data 1)
212*
Default value
100
100
Fine exact stop
Negative axis
direction
Zero-speed monitoring
The NC monitors the position at zero speed (holding of position). If the zero-speed monitor is
timed out after the waiting time for the position monitor (NC MD 156/NC MD 372*) has
elapsed, alarm 112* is issued.
The following situations may occur:
a) If the interface controller revokes the servo enable signal for an axis, the NC can no longer
hold that axis in position. The interface controller must hold the axis in position itself by
means of clamping. However, the clamped axis may be forced out of position as a result
of mechanical forces.
b) The axis may be forced out of position as a result of major mechanical forces or faults in
the drive.
The value for zero-speed monitoring must be greater than the tolerance ranges for fine
stop and coarse stop.
Note:
As from SW 4, for 8 parameter sets
6–40
Zero-speed monitoring
Lower input limit Upper input limit
0
0 99 999 999
(as from SW 4.4)
SET POSITION
Coarse exact
stop
©
Siemens AG 1992 All Rights Reserved
Units
16 000 units (MS)
units (MS)
Positive axis
direction
ACTUAL
POSITION
6FC5197- AA50
SINUMERIK 840C (IA)
03.95
Active on
NC Stop