Siemens SINUMERIK 840C Operator's Manual page 137

4 Machine
Search with
calculation
Sea rch with
calculation
Note
DSB and block
search
4-70
Press the SEARCH WITH CALCULATION softkey. The block search is
carried out by the control.
After NC START the program is started and executed.
During block search with calculation, the same calculations are carried out as
in normal program operation but the axes do not move.
It is also possible to perform a block search in a nest of subroutines. For this,
you enter in the main program, the number of the block in which the subroutine
call is programmed. Then, you input the number, the number of passes and the
block number of the subroutine and operate the softkey. Operating NC START
triggers a compensatory movement with linear interpolation to the end point of
the target block. When doing so, observe the feedrates and axis compensations
configured by the machine manufacturer. If the target block is a block with G4
dwell, this is not activated. The compensatory movement then goes to the last
position programmed. If G00 from the program is active in a target block, the
compensatory movement is executed with G00. The display gives the G
command which is active for the program
In blocks with contour definition, tool radius compensation or soft approach to
contour, the PROGRAM START key must be pressed several times before the
axis moves or the message "Block search terminated" is displayed (cause: e.g.
calculation of the intersection point of the tool radius compensation requires at
least two blocks).
With decoding single block it is possible that several blocks are traversed when
pressing the PROGRAM START key once (e.g. tool radius compensation).
Since the coordinate blocks of the spline blocks (spline interpolation) can only
be programmed with block numbers, a block search with calculation can only
be performed for coordinate blocks and not for coefficient blocks.
Two applications are significant regarding the "Search with calculation" and
"Search from main block" functions in conjunction with the Decoding Single
Block (DSB) function:
• DSB function activated before search start
All blocks including the target block are calculated. The blocks after the
target block are not decoded in advance. It is therefore possible to edit
blocks directly after the target block. These blocks are effective as soon as
NC START is pressed. Arithmetic blocks following the target block are
displayed after NC START. If the functions "Contour definition", "Soft
approach to/from the contour" and/or tool radius compensation are active,
the signal "Block search terminated" is not output. The signal is not output
before the next NC START.
6FC5198-6AA60-0BP1 © Siemens AG 1999 All Rights Reserved
SINUMERIK 840C, OEM Version for Windows (BA)
01.99