Siemens SINUMERIK 840D Description Of Functions page 371

11.03
Further, it must be noted that the ASUB (SAFE.SPF in the directory CST.DIR)
must be started in channel 1 for the NCK-SPL in order that the SPL completely
runs-up.
Once FB4 has been successfully executed, the ASUB is started with function
FC9. Here it is important that the FC9 bit "Done" is interrogated in order that the
program can continue. This is because the PLC-SPL can only be started once
the ASUB start task has been completed.
In addition to the FC9 bit "Done", the interface bit "Channel 1-M02/M17/M30
active – DB21.DBX33.5" is also logically combined in order to identify that the
ASUB has been completely executed. It might be possible for a user-written
M function to be output at the end of ASUB instead of using M02/M17/M30.
7.3.3 Declaring variables
Description The individual SPL variables must be declared in the NCK-SPL and the
PLC-SPL.
On the PLC side, the I/O input and output bits and the Safety Integrated SGEs
and SGAs are transferred to DB 18 or supplied from DB18. The PLC-SPL only
has to be programmed with the variables of DB18 (exception, test stop and the
forced-checking procedure of the inputs and outputs).
To ensure clear configuration and programming, it is necessary to list the
variables used and to document their meaning. A suggestion for how to do this
is documented below. To achieve clarity and uniform formatting, a separate
declaration table is created both for the NCK and for the PLC sides. For
diagnostics and support during the commissioning phase, both of these tables
should be considered as a single-entity in order to clearly represent cross-
references.
The two variable tables which are relevant for programming SPL (PLC and
NCK sides)
When programming the PLC-SPL, please not that the "worst-case" response
time of the PLC also applies. This means, that under worst case conditions, a
time difference of 2 PLC cycle times can expire between changing the input
signal and the appropriate change of the associated output signal.
A bitwise (bit-serial) overview of the individual signals of the DB18 is provided
in the Appendix (Subsection 7.3.12).
A list of the complete NCK-SPL program and the PLC modules that are
required for the PLC-SPL is given in Chapter 7.3.10 or Chapter 7.3.11.
© Siemens AG 2003 All Rights Reserved
SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
7 Configuring example
7.3 Safety Integrated with SPL
7-371