3 Safety-Related Functions
11.03
3.9 Safety-related input/output signals (SGE/SGA)
© Siemens AG 2003 All Rights Reserved
3-128
SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
Processing in the drive monitoring channel
Safety functions can be selected/de-selected independently of the NC
operating mode
Differences between the active SGEs in the monitoring channels are detected
by the crosswise data comparison.
A two-channel structure (see Fig. 3-21 "NCK and drive monitoring channels") is
provided for the input/output and processing of safety-relevant input/output
signals. All requests and checkback signals relating to safety-relevant functions
must be entered or retrieved through 2-channels via both monitoring channels.
Process
Machine
HW
inputs/
out-
puts
HW-
Inputs/
out-
puts
NCK
signal
proces-
sing
NCK
SGE/SGAs
Comparator
Data
PLC
signal
proces-
sing
NC/PLC
interface
Axis/spindle
DB
Comparator
Data
SGESGA03.DSF
NCK monitoring channel
Drive monitoring channel
System
Interface
Interface
NCK signal-
processing
PLC signal
processing
NCK
I/O devices
PLC
I/O devices
Result and data
cross-check
Fig. 3-27
NCK and drive monitoring channels
For the NCK monitoring channel, the signals are input and output via the
NCK I/O devices, processed by the NCK logic operations block and mapped in
the SGE/SGA interface.
The signals from the drive monitoring channel are input/output via the PLC I/O
devices, processed by the PLC user program and transferred to the drive or the
PLC via the NC/PLC interface.
Two-channel
processing of I/O
signals for NC and
drive