Allen-Bradley 1794-IB16D, Installation Instructions Manual

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FLEX I/O Digital Input and Output Modules with Diagnostics 11
Publication 1794-IN096D-EN-P - June 2018
Diagnostics
See configuration information below for location of diagnostic bits.
Note: Each unused sensor port requires a dummy resistor to mask the channel diagnostic
function.
Diagnostic Functions for the 1794-IB16D
Ext.
Power Wiring Input
Status Channel
LED
Status Open
Wire
Error Bit Short
Error Bit Rev.
Error Bit Module
Error
Bit/LED
OFF Open Off Off 0 0 0 0/OFF
On Off 0 0 0 0/OFF
Short Off Off 0 0 0 0/OFF
On Off 0 0 0 0/OFF
Normal Off Off 0 0 0 0/OFF
On Off 0 0 0 0/OFF
ON Open Off RED 1 0 0 1/RED
On RED/YEL 1 0 0 1/RED
Short Off RED 0 1 0 1/RED
On RED/YEL 0 1 0 1/RED
Normal Off Off 0 0 0 0/OFF
On YEL 0 0 0 0/OFF
REV Open Off Off 0 0 1 1/RED
On Off 0 0 1 1/RED
Short Off Off 0 0 1 1/RED
On Off 0 0 1 1/RED
Normal Off Off 0 0 1 1/RED
On Off 0 0 1 1/RED
The module monitors each sensor-power port for current and voltage. It turns on the channel red LED and
sets (1) the error bit when 1) the module detects a short circuit (no voltage at the sensor-port), and 2) the
module detects an open wire ( no current at the sensor-port).