Siemens SINUMERIK 840D sl Function Manual page 595

2.5 Block search
Functionality
Block search offers the possibility of starting part program execution from almost any part
program block. This involves the NC rapidly performing an internal run through the part
program (without traversing motions) to the selected target block.
Here, every effort is made to achieve to the exact same control status as would result at the
target block during normal part program execution (e.g., with respect to axis positions,
spindle speeds, loaded tools, NC/PLC interface signals, variable values) in order to be able
to resume automatic part program execution from the target block with minimum manual
intervention.
Block search types
• Type 1: Block search without calculation
• Type 2: Block search with calculation at contour
• Type 4: Block search with calculation at block end point
• Type 5: Block search with calculation in mode: "Program test" (SERUPRO)
Basic logic functions: Mode group, channel, program operation, reset response (K1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0
Block search without calculation is used to find a part program block in the quickest
possible way. No calculation of any type is performed. The control status at the target
block remains unchanged compared to the status before the start of the block search.
Block search with calculation at contour is used to enable the programmed contour to be
approached in any situation. On NC Start, the start position of the target block or the end
position of the block before the target block is approached. This is traversed up to the end
position. Processing is true to contour.
Block search with calculation at block end point is used to enable a target position (e.g.,
tool change position) to be approached in any situation. The end position of the target
block or the next programmed position is approached using the type of interpolation valid
in the target block. This is not true to contour.
Only the axes programmed in the target block are moved. If necessary, a collision-free
initial situation must be created manually on the machine in "JOG REPOS" mode before
the start of further automatic part program execution.
SERUPRO (search run by programtest) is a cross-channel block search with calculation.
Here, the NC starts the selected part program in "Program test" mode. On reaching the
target block, the program test is automatically deselected. This type of block search also
enables interactions between the channel in which the block search is being performed
and synchronized actions as well as with other NC channels.
Note
For further information about block searches, please see:
References:
/FB1/Function Manual, Basic Functions; Auxiliary Function Output to PLC (H2),
Section: "Behavior on block search"
Detailed description
2.5 Block search
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