Siemens SINUMERIK 840D sl Function Manual page 815

Reciprocating axes
Reciprocating axes always brake at their reversal position and then move in the opposite
direction. Therefore, reciprocating axes do not require an expansion.
Note
The behavior of PLC axes at block changes is described in Section "Control by the PLC".
For further information about block changes with programmed end-of-motion criteria FINEA,
COARESA and IPOENDA , please refer to:
References:
/FB1/ Function Manual, Basic Functions; Spindles (S1), Section "Spindle modes"
/FB1/ Function Manual, Basic Functions; Feedrates (V1), Section "Programmable dynamic
response of single axes"
IPOBRKA
When the NC command IPOBRKA is issued, the end-of-motion criterion is activated in the
braking ramp either
● in the part program: Block change in the part program or
● in synchronized action: Technology cycles
With SW 6.2 and higher,type 2 positioning axis behavior differs from that in previous
software versions as follows:
If POSA is programmed, then POSA again with IPOBRKA (block change in the braking ramp),
an alarm is not issued. The new POSA motion waits for the preceding POSA motion to have
reached the block change point in the braking ramp.
Condition for block change
If the end-of-motion criteria for all axes/spindles to be operated in the block are fulfilled in
addition to the block change condition, then block change takes place. This applies both to
part program blocks and for technology cycle blocks.
Block change condition braking ramp in SD43600
SD43600 $SA_IPOBRAKE_BLOCK_EXCHANGE
The above setting data "Block change condition braking ramp" can be set to define the
moment of block change for single-axis interpolation to between the activation instant of the
braking ramp with 100% to IPO stop with 0%.
With a setting of 100%, the block change condition of the positioning axis is already fulfilled
when the braking ramp is activated.
With a setting of 0%, the block change condition is identical to IPOENDA.
Extended Functions
Function Manual, 03/2009, 6FC5397-1BP10-4BA0
Positioning Axes (P2)
Block change
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