3 Safety-Related Functions
11.03
3.10 Safe programable logic (SPL) (840D SW 4.4.18)
© Siemens AG 2003 All Rights Reserved
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SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
3.10 Safe programable logic (SPL) (840D SW 4.4.18)
Until now, safety-relevant signals were processed in external logic.
SPL, which comprises NCK-SPL and PLC-SPL greatly reduces the amount of
external wiring required. The logic used up until now has been replaced by a
written program (SPL).
Features:
•
Logic operations implemented by the user are cyclically processed
•
Instructions are effective in all operating modes
•
The instructions immediately start after the control system runs-up
In order to check that the two SPLs (PLC and NCK) are functioning, a cyclic
data comparison between the PLC and NCK is organized by the system
program. Monitoring is performed both by the NCK-CPU and the PLC-CPU
independently. This involves a crosswise data comparison of the signals that
are input into the SPL and the safety-relevant signals generated by the SPL as
well as internal states (markers).
Direct connection of max. 64
safety-related sensors
(e.g.: mode switch, light barrier,
EMERGENCY OFF, ...)
Connection of max. 64
safety-related actuators
(e.g.: protective door locking,
motor brakes, ...)
PLC
combinational
logic
Event and data
cross-checking
SGAs
SGAs
SGEs
NCK
combinational
logic
SGEs
SPL_12.dsf
Fig. 3-32
Safe programmable logic
Drive monitoring channel:
The SGEs/SGAs can be logically combined in different ways as defined in the
PLC user program and the result output at the interface or PLC I/Os.
NCK monitoring channel:
The SGEs/SGAs are assigned via input and output assignments that can be
parameterized via machine data.
The input signals can be processed by multiple distribution (1 input is assigned
to several axes) and the output signals by multiple assignment (signals of
several axes are assigned to 1 output).
Multiple distribution/assignment can also be parameterized via machine data.
Signals in this channel cannot be subject to other logic operations.
Function
Logic operations up to
and including
SW 4.4.12
