Siemens SINUMERIK 840D sl Function Manual page 1682

Detailed Description
2.5 Programming
2.5.3 Programming spindle controls via the PLC with FC18
Automatic gear step change with FC18
When the PLC specifies the direction of rotation and speed using FC18, the NCK can
determine and select a gear step to match the speed. This is equivalent to the M40
functionality when programming via the part program.
The correct start code must be set when FC18 is called in a PLC user program, in order to
activate gear step selection.
More detailed explanations regarding the programming of spindle controls by PLC with FC18
can be found under:
Literature:
/FB1/ Function Manual, Basic Functions; PLC Basic Program (P3)
2.5.4 Special spindle movements via PLC interface
Why use a special spindle interface?
This function can be used to program the spindle via an axial PLC interface as an alternative
to the FC18. The simplicity of the settings results in slightly restricted functionality. This
functionality can be used preferably for simple control applications.
Functionality
Special VDI interface signals are provided to start and stop spindles outside a running part
program. In this regard, the channel status and the program status need not be in the active
mode. These states will occur, e.g., on RESET and in JOG mode.
The spindle concerned must have the state "Channel axis" or "Neutral axis" and must not be
moved using the JOG keys or positioned by FC18 or synchronized actions. If these
conditions are fulfilled, spindle jobs will be accepted via the DBB30 spindle interface.
The spindle settings are retained after a change in mode (e.g., from JOG mode to
AUTOMATIC). The spindle settings (direction of rotation, speed or cutting rate) are applied
to the part program at the start of the program and can be modified again using part-program
instructions. In JOG mode, the spindle can be moved at the speed last programmed.
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Basic logic functions: Spindles (S1)
Function Manual, 11/2006, 6FC5397-0BP10-2BA0