Siemens SINUMERIK 840D sl Function Manual page 782

Positioning Axes (P2)
11.6 Block change
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 $SA_IPOBRAKE_BLOCK_EXCHANGE
The above setting data "Block change condition braking ramp" can be set to define the
moment of block change for single-axis interpolation to between the activation instant of the
braking ramp with 100% to IPO stop with 0%.
With a setting of 100%, the block change condition of the positioning axis is already fulfilled
when the braking ramp is activated.
With a setting of 0%, the block change condition is identical to IPOENDA.
Advantages of the percent setting
Setting SD43600 in percent offers the following advantages:
● The block change condition is not dependent on a position and is therefore dependent on
● Maximum override will result in the greatest smoothing deviation.
● A smaller override will reduce the deviation.
The braking ramp block change condition can be queried like the previous axial end-of-
motion criteria with$AA_MOTEND[axis] = 4
Braking ramp with tolerance window
Additional block change condition in braking ramp
An additional block change condition tolerance window can be selected as well as the
existing block change condition in the braking ramp. Release will only occur when the axis
● as before has reached the specified % value of its braking ramp and
● its current actual or set position is no further than an adjustable tolerance from the end of
The latest the axis is available is when the interpolator reaches the end position. The
tolerance window is modal.
The following applies to the braking ramp with tolerance window block change condition:
The setpoint position is signaled with $AA_MOTEND[axis] = 5
The actual position is signaled with $AA_MOTEND[axis] = 6
782
the override set.
the axis in the block.
Function Manual, 01/2008, 6FC5397-1BP10-3BA0
Extended Functions