Siemens SINUMERIK 840D Description Of Functions page 129

11.03
3.9 Safety-related input/output signals (SGE/SGA)
Fig. 3-28
The data and results in the two mutually independent monitoring channels are
subject to a crosswise data comparison. If any discrepancy is found, STOP F is
activated.
Basic principle of safe For a two-channel control structure, only a single-channel signal feedback via
signal processing the PLC is needed.
In contrast, when a single-channel control structure is used, a redundant, i.e. a
two-channel feedback structure is required.
What SGEs/SGAs are The following SGEs and SGAs are provided for each axis/spindle in each of the
there? two monitoring channels:
© Siemens AG 2003 All Rights Reserved
SINUMERIK 840D/SIMODRIVE 611 digital SINUMERIK Safety Integrated (FBSI) - Edition 11.03
NCK
HW I/O images
I/O
I1
I2
...
In
O1
O2
...
...
O_Fign
On
Machine
I1
I2
...
In
O1
O2
...
...
On
PLC
HW
I/O images
I/O
Process
Two-channel processing of I/O signals
Note
Owing to the two-channel structure of Safety Integrated, the machine
manufacturer must supply the SGEs and SGAs in both the NCK monitoring
channel and the drive monitoring channel.
The actual signal status of the SGEs/SGAs is selected via the menu "Service
display". The "Service SI" window displays information about Safety
Integrated data together with the associated axis name and axis number.
3 Safety-Related Functions
SGE
Processing
monitoring channel
SGA
I_Fig1
SGE ...
per axis/spindle
I_Fig2
SGE ...
Multiple
SBH/SG
...
distribution
...
SE
SGE ...
I_Fign
SN
O_Fig1
SGA ...
SGA ... Monitoring
O_Fig2
Multiple
comparators
assignment
...
SGA...
Result and data
cross-check
I_Fig1 SGE ...
per axis/spindle
PLC
I_Fig2 SGE ...
user SBH/SG
...
...
program
SE
I_Fign SN
SGE ...
O_Fig1
SGA ...
PLC
Monitoring
O_Fig2 SGA ...
user
comparators
program
O_Fign
SGA...
SGE
Drive monitoring channel
Processing
SGA
User System
NCK
SGESGA01.DS4
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