Siemens SINUMERIK 840C - Manual (Page 409)

6 NC Machine Data (NC MD), NC Setting Data (NC SD) 08.96
6.12.1 NC setting data (NC SD)
The setting data can be written from a part program under "Program control" using the
command @410 or from the PLC. A larger value can be written as the available block memory.
The NC however still predecodes no more than the stated number of blocks. If the setting data
is reduced when already more than the defined number of blocks has been predecoded, no
more blocks are predecoded until this number is reached.
Limitation is especially useful when a program is being run in (single block processing).
Actual number of predecoded blocks (as from SW 5) 206*
Default value Lower input limit Upper input limit Units
Blocks
Active on
–
The number of blocks actually predecoded by the NC can be read in setting data 206*. The
inserted blocks in the block preparation chain are also counted.
The value is displayed under "Program control" but can also be read in the part program
(@310) by the PLC. The user can use this command to control predecoding from the PLC
(see also function ”Control of predecoding G171/G172”).
The value must not be overwritten. It is constantly updated by the NC when the part program
is active.
Note:
The actual number of predecoded blocks never reaches the value set in the memory
configuration because up to 20 buffers are used for internal memory management.
Minimum working area limitation 300*
Default value Lower input limit Upper input limit Units
– 99 999.999 – 99 999.999 + 99 999.999 mm or inches
Active on
–
Maximum working area limitation 304*
Default value Lower input limit Upper input limit Units
+ 99999.999 – 99 999.999 + 99 999.999 mm or inches
Active on
–
With working are limitation, the range of travel can be limited in automatic, and/or JOG mode
(in addition to software limit switches). The axes are displayed for each mode group. The
working area limitation can be altered in the program with G25/26.
Working are limitation has no effect in the ”Reference point approach mode”.
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SINUMERIK 840C (IA)