Rockwell Automation 1715-OF8I Redundant I/O System User Manual - Manual (Page 82)

82 Rockwell Automation Publication 1715-UM001C-EN-P - March 2014
Chapter 2 Installation Instructions
1715-IF16 Digital Input Module Functional Block Diagram
Figure 32 - 1715-IF16 16-channel Module Functional Block Diagram
Figure 32 provides a Function Block Diagram of the 1715 digital input module
illustrating the input circuits, isolation circuits, internal power supplies and the
input data management by the FPGA. Each input signal is routed through a
termination assembly to two input measurement devices. These devices
determine the input status and channel condition and generate the input data for
the ControlLogix controller.
The digital input module receives commands from the adapter module and
converts the channel input data into secure digital data packets. Signal power and
isolation circuits separate out each input channel from the rest of the system and
protect the system components from field faults.
Module power is produced by the internal isolated power supply from the 24V
DC dual redundant system power inputs. The isolated power supply provides
power to the module and is protected by over-voltage and under-voltage
detection circuits. Supply voltage monitoring initiates a warning signal and
Power-off Protection mode when a power failure is detected.
Internal diagnostics test the module every application cycle to see whether values
are within the 1%-value fault band, and if appropriate, report a fault.
Channel 0
Channel 1
Channel 2
Channel 3
Channel 4
Channel 5
Channel 6
Channel 7
Field
Inputs
Termination
Assembly
Dual
Redundant
System
Power
SYS_24V1
SYS_24V2
SYS_OV
Dual Input
Measurement
Device
Isolated
Power
Supply Over/Under
Voltage
Protection PWR
Power
Valid
Isolator
PWR
CMD
RES
PWR
CMD
RES
PWR
CMD
RES
PWR
CMD
RES
PWR
CMD
RES
PWR
CMD
RES
PWR
CMD
RES
Dual Input
Measurement
Device
Isolator
PWR
CMD
RES
PWR
CMD
Input Data
Data Management
FPGA
PWR Power
Valid
SPI
Flash
PMA Commands
PMB Commands
PM Commands
I/O Command Bus
Response Bus
Front Panel
LEDS
I/O Backplane
Input Data
Module Status
Channel Status
32106-M
Typical Circuit