Siemens SINUMERIK 840D sl Function Manual page 182

Connecting Sensors/Actuators
7.1 Safety–related input/output signals
Motor
PROFIsafe
Process
Fig. 7-1 NCK and drive monitoring channel
For the NCK monitoring channel, signals are input/output via the SPL – possibly
processed by the NCK (see Chapter 7.1.5 "Multiple distribution and multiple inter-
locking") and emulated (mapped) in the NCK–SGE/SGA interface.
The signals from the drive monitoring channel are input/output via the SPL and
sent to the drive via the interface axis/spindle DB.
Internal SGE/SGA (interface to the various axial safety functions) are, e.g. select-
ing and deselecting safety functions, changing–over limit values, output of status
signals. They are defined for the particular Safety Integrated functions.
Sensors – e.g. switches, pushbuttons, protective door contacts, emergency stop
buttons, light curtains, laser scanners – are connected to the external SGE (inter-
face to the process, i.e. to the machine). Actuators – e.g. load contactors, valves,
interlocking solenoids – are connected to the external SGA. The connection is es-
tablished through the PROFIsafe I/O, also see Chapter 7.2. Generally, a brake is
directly connected at the Motor Modules via terminals.
The external and internal SGE/SGA are freely interlocked (logically combined) by
the user using the "safe programmable logic" (SPL), also see Chapter 7.3.
Crosswise data comparison is implemented between the monitoring channels that
operate independently of one another. If there is inequality, then a STOP F is initi-
ated (crosswise data comparison between the drive and NCK).
7-182
SINUMERIK 840D sl/SINAMICS S120 SINUMERIK Safety Integrated (FBSI sl) – 05.2008 Edition
External
SGE/SGA
NCK signal processing
CDC
Bus
PLC signal processing
Internal
SGE/SGA
Interface
NCK– NCK
SPL SGE/SGA
signals
NCK monitoring channel
CDC
Drive monitoring channel
NC/PLC
interface:
PLC–
SPL
Axis/
spindle DB
Interface
System
© Siemens AG 2008 All Rights Reserved
05.08
Comparator
Data
CDC
Comparator
Data