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Rockwell Automation Publication 1715-UM001J-EN-P - December 2020
Chapter 8 Using SIL 2 Add-On Instructions with 1715 Redundant I/O Modules
Figure 70 - Diagram of Output Module Add-On Instruction
SIL 2 Check Data
The instructions gather data from the module-defined configuration tags for
the following check data values
.
IO BASE
1715-A310
CH1
CH1
CH1
CH1
CH1
CH1
CH1
CH1
TERMINAL IDENTITY
AOTA
Dual.
CH1
CH1
CH1
CH1
CH1
CH1
CH1
CH1
TERMINAL IDENTITY
AOTA
Dual.
CH1
CH1
CH1
CH1
CH1
CH1
CH1
CH1
TERMINAL IDENTITY
AOTA
Dual.
1715-AENTR
1715-AENTR
1715-
OF8
1715-
OF8
1715-A2A
1715-A3IO
1715-
TASOF8
1715-
TASOF8
OF8_Duplex_SIL2 Add-On Instruction
1715-OF8 Data Packet
SIL 2 Check Data
1715-OF8 Configuration Tag
Safe State Defaults
Module Configuration
Check Data
SIL 2 Check Data
Module Configuration
Check Data
Safe State Defaults
Input Data (status)
Input Data
Reconciled
Input Data
The Add-On
Instruction verifies
the check data.
Da
ta
is
va
lid
.
Dat
a is
no
t va
lid.
1756 Controller Tags
Input Data System
Output Data System
1756 Controller Tags
1715-OF8 Configuration Tag
Requested
Output Data
Module Configuration
Check Data
OF8_Duplex_SIL2 Add-On Instruction
IO BASE
1715-A310
CH1
CH1
CH1
CH1
CH1
CH1
CH1
CH1
TERMINAL IDENTITY
AOTA
Dual.
CH1
CH1
CH1
CH1
CH1
CH1
CH1
CH1
TERMINAL IDENTITY
AOTA
Dual.
CH1
CH1
CH1
CH1
CH1
CH1
CH1
CH1
TERMINAL IDENTITY
AOTA
Dual.
1715-AENTR
1715-AENTR
1715-
OF8
1715-
OF8
1715-A2A
1715-A3IO
1715-
TASOF8
1715-
TASOF8
Requested
Output Data
Module Configuration
Check Data
1715-OF8 Input Data Packet
Generate Sequence
Number
Generate CRC
Output Data
Output Data
The Add-On Instruction
adds the check data to the
requested output data and
generates a sequence
number and CRC to
generate the output
data packet
Reconciled
Input Data
Important: The 1715-OF8 module is shown, but the example also applies to the 1715-OB8DE module.