Starting Concurrent Positioning Axes From The Plc - Siemens SINUMERIK 840D sl Function Manual

The channel-specific interface signal PLC→NCK
● IS DB21, ... DBX6.0 ("feed disable") does apply to a PLC-controlled axis if bit 6 = 0 in
The channel-specific VDI interface signal NCK→PLC
● IS DB21, ... DBX36.3 ("all axes stationary") is set only if bit 7 = 0 in machine data
Alarm 26075 is generated if an attempt is made to assign an axis under exclusive PLC
control to the NC program or to request the axis for the program. Alarm 26076 is generated
in the same way for a PLC axis with fixed assignment.
A PLC axis with fixed assignment is a "neutral axis" on power up. When a traverse request is
transferred via the VDI interface, a concurrent positioning axis automatically changes to a
PLC axis without being replaced beforehand.
Axis replacement via PLC
The type of an axis for axis replacement is transferred to the PLC with axial interface byte
NCK→PLC NST DB31, ... DBB68:
● IS DB31, ... DBX68.0-68.3 ("NC axis/spindle in channel") channels 1 to 10
● IS DB31, ... DBX68.4 ("new type requested by PLC")
● IS DB31, ... DBX68.5 ("axis can be replaced")
● IS DB31, ... DBX68.6 ("neutral axis/spindle")
● IS DB31, ... DBX68.7 ("PLC axis/spindle")
If IS DB31, ... DBX68.5 ("axis can be replaced") == 1, an axis replacement request can be
issued from the PLC.
References: /FB2/ Function Manual, Extended Functions; "Mode Groups, ... Axis
Replacement" (K5)
11.7.1

Starting concurrent positioning axes from the PLC

Activation from PLC
When concurrent positioning axes are activated from the PLC, FC18 is called and supplied
with the following parameter data:
● Axis name or axis number
● End position
● Feedrate (with feedrate setting = 0, the feedrate is determined by the setting in machine
● Absolute coordinate (G90),
Extended Functions
Function Manual, 01/2008, 6FC5397-1BP10-3BA0
machine data
MD30460 $MA_BASE_FUNCTION_MASK.
MD30460 $MA_BASE_FUNCTION_MASK.
data MD32060 $MA_POS_AX_VELO):
incremental coordinate (G91),
absolute coordinate along the shortest path for rotary axes (rotary axis name =
DC(value))
Positioning Axes (P2)
11.7 Control by the PLC
789