Siemens SINUMERIK 840C - Manual (Page 291)

6 NC Machine Data (NC MD), NC Setting Data (NC SD) 07.97
6.6.1 General MD bits (general bits)
7 6 5 4 3 2 1 0
Bit No.
NC MD
5025
Reload
workpiece
on power
on (as from
SW 2)
Endlessly
turning
rotary axis
Alarm ”Axis
not in C
axis mode”
Travel thru
transform.
center
(as from
SW 5)
Extended
threading
package
Axis-
specific
G functions
to PLC
Bit 7 Bit 7=1 The last active workpiece is reloaded channel-specifically in the NCK CPU on
warm restart. This can only be done if a workpiece was already loaded or had
been selected before switching off, i.e. the workpiece pointers are
preassigned. The workpieces are loaded in order into channel 1 to channel n.
The order in which the workpieces were loaded before the control was
switched off no longer applies. Loading of workpiece STANDARD is always
executed before the function ”Reload workpiece ...” and cannot be disabled
via machine data. Please note that the function can also alter data (TOA, ZOA,
etc.) which might have been manipulated on the NCK before switching off the
control if any of them are overwritten by the job concerned.
Note:
Workpiece loading can be disabled channel-specifically. See setting data 540*.
Bit 6 Bit 6 =1 The function ”Endlessly turning rotary axis” is activated (see Functional
Description).
Bit 5 Bit 5 =1 This bit is activated via the toggle field in the display NC machine data/Gen.
data/Basic data under the intermediate heading "General basic data".
Bit 3 Change as from SW 5:
Independent of this bit
• it is possible to travel through the transformation center in JOG mode.
Previously the alarm "Speed setpoint warning limit" was triggered in this
case.
• the velocity of the rotary axis is always limited to the maximum possible
value.
• see also Functional Description: Coordinate transformation in Section 12.
Bit 3=1 Activates the function "Travel through the transformation center". It is possible
both to machine contours near the turning center faster than before and to
travel through the transformation center. The permissible feedrate in the
fictitious coordinate system is calculated as a function of the current distance
from the center of turning and the MD "Maximum velocity rotary axis" so that
the path feedrate changes continuously.
Bit 3=0 Activates the previous functionality: With the function Transmit, note that the
rotary axis must rotate faster the nearer the contour is to the turning center.
The maximum velocity of the rotary axis entered in MD 280* must not be
exceeded.
This is achieved by traversing the entire contour of a part program with a lower
speed in the fictitious coordinate system. This velocity is chosen such that at
the point which is closest to the center of turning within the contour, the
velocity of the rotary axis is not exceeded. This method has the disadvantage
that the velocity is also lower in parts of the contour that are farther away from
the turning center.
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SINUMERIK 840C (IA)