Allen-Bradley 1756-L6 Series, Reference Manual, Page: 20 / 134

20 Rockwell Automation Publication 1756-RM001I-EN-P - May 2012
Chapter 1 SIL Policy
Figure 8 - Duplex System ControlNet Configuration
The duplex system configuration uses safety and programming principles
described in this manual, as well as programming and hardware described in the
application technique manuals.
For more information about the ControlLogix SIL 2- certified fault-tolerant
system, see the application technique manual that corresponds with your
application.
Proof Tests IEC 61508 requires the user to perform various proof tests of the equipment used
in the system. Proof tests are performed at user-defined times (for example, proof
test intervals can be once a year, once every two years or whatever time frame is
appropriate based on the SIL verification calculation) and could include some of
the following tests:
• Test all safety application fault routines to verify that process parameters
are monitored properly and the system reacts properly when a fault
condition arises.
Primary Chassis
Secondary Chassis
ControlNet
PRI COM OK
PRI COM OK
I/O Chassis A
I/O Chassis B
ST
ST
DIAGNOSTIC
O
K
0 1 2 3 4 5 6 7
8 9 10 1112 13 14 15
DC INTPUT
ST
ST
DIAGNOSTIC
O
K
0 1 2 3 4 5 6 7
8 9 10 1112 13 14 15
DC INTPUT ANALOG INTPUT
CAL
OK
ANALOG INTPUT
CAL
OK
ST
ST
DIAGNOSTIC
O
K
0 1 2 3 4 5 6 7
8 9 10 1112 13 14 15
DC OUTPUT
ST
ST
DIAGNOSTIC
O
K
0 1 2 3 4 5 6 7
8 9 10 1112 13 14 15
DC OUTPUT
ST
ST
DIAGNOSTIC
O
K 0 1 2 3 4 5 6 7
8 9 10 1112 13 14 15
DC INTPUT
ST
ST
DIAGNOSTIC
O
K 0 1 2 3 4 5 6 7
8 9 10 1112 13 14 15
DC INTPUT ANALOG INTPUT
CAL
OK
ANALOG INTPUT
CAL
OK
ST
ST
DIAGNOSTIC
O
K 0 1 2 3 4 5 6 7
8 9 10 1112 13 14 15
DC OUTPUT
ST
ST
DIAGNOSTIC
O
K 0 1 2 3 4 5 6 7
8 9 10 1112 13 14 15
DC OUTPUT
Field Device Field Device Field Device
Analog Input
Termination
Board Digital Input
Termination
Board Digital Output
Termination
Board
SIL 2-certified ControlLogix Safety Loop
If using Then reference this manual
SIL 2 Fault-tolerant I/O subroutines
(available for use with RSLogix 5000 software,
version 15 and later) ControlLogix SIL 2 System Configuration Using RSLogix 5000
Subroutines, publication
1756-AT010
SIL 2 Fault-tolerant I/O Add-On Instructions
(available for use with RSLogix 5000 software,
version 16 and later) ControlLogix SIL 2 System Configuration Using RSLogix 5000
Subroutines, publication
1756-AT012