Supplementary Conditions; Block Change And Positioning Axes; Block Change Delay; Rounding And Repositioning (Repos) - Siemens SINUMERIK 828D Function Manual

B1: Continuous­path Mode, Exact Stop, LookAhead

3.9 Supplementary conditions

3.9 Supplementary conditions
3.9.1

Block change and positioning axes

If path axes are traversed in continuous path mode in a part program, traversing positioning axes can also
simultaneously affect both the response of the path axes and the block change.
A detailed description of the positioning axes can be found in:
References:
Function Manual, Extended Functions; Positioning axes (P2)
3.9.2

Block change delay

Even if all path axes and special axes traversing in the part program block have satisfied their specific block
transition criteria, the block change can still be delayed due to other unsatisfied conditions and/or active
functions:
Examples:
• Missing auxiliary function acknowledgement by the PLC
• Non-existent following blocks
• Active function "Empty buffer"
Effects
If a block change cannot be executed in continuous path mode, all axes programmed in this part program block
(except cross-block traversing special axes) are stopped. In this case, contour errors do not occur.
The stopping of path axes during machining can cause undercuts on the workpiece surface.
3.9.3

Rounding and repositioning (REPOS)

Repositioning within the rounding area
If the traversing motion of the path axes within the rounding area is interrupted for traversing blocks with
programmed rounding (part program command G641, G642, G643, G644 or G645), repositioning occurs as
follows in the event of a subsequent REPOS operation, depending on the current REPOS mode:
REPOS mode REPOS end point
RMB Block start of interrupted traversing block
RMI Block end of interrupted traversing block
RME Block end of interrupted traversing block
RMN Block end of interrupted traversing block
210
Function Manual, 09/2011, 6FC5397-0BP40-2BA0
Basic Functions