Siemens sinumerik 840D sl Function Manual page 746

Figure 2-2
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Special functions: Retrace Support (TE7)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
Signal chart
Reverse travel is initiated
Forward travel is initiated (optional)
Retrace support is initiated (block search)
Search target (target block) located
1st NC START → Action blocks are output
Last action block is active
When the last action block is activated, the RESU ASUB
CC_RESU_BS_ASUP.SPF is initiated
2nd NC START →Return travel to approach block for program continuation point
Part program processing (target block) resumed
Detailed description
2.1 Functional description
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