Rockwell Automation Allen-Bradley 1794-IB16D - Page 22

22 Rockwell Automation Publication 1794-UM061B-EN-P - March 2020
Chapter 2 About the FLEX I/O Diagnostic Input Module
Wiring Input Sensors
You must use a 1794-TB32 or 1794-TB32S terminal base unit with the
1794-IB16D diagnostic input module. See FLEX I/O Digital Input and Output
Modules with Diagnostics Installation Instructions, publication 1794-IN096
for
complete information.
Two-wire input devices connect to the input and sensor power terminals; 3-wire
devices use input, sensor power, and common terminals. You can wire 2-wire and
3-wire sensors to the FLEX I/O 1794-TB32 or 1794-TB32S terminal base units.
Unused sensor-power ports or open-contact input devices must use a dummy
resistor to mask the diagnostic function. If these external resistors are not used,
the module’s fault indicator will light, along with the module’s error bits, thus
rendering fault detection of the remaining channels useless. The recommended
value of this dummy resistor is 20 k(+
10%), 1/8 watt (or larger). Connect the
resistor between sensor power and input signal or between sensor power and
common.
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
16
35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51
34
COM1NC
Sensor Common and User Power Common:
Input Channels 0-15
NC
Sensor Power Terminals for Channels 0-15
+V1 COM1 +V1 COM1 +V1 COM1
+V1
+V2 COM2 +V2 COM2 +V2 COM2 +V2 COM2 NC
Terminals C-36, C-38, C-40, C-42, C-44, C-46, C-48 and C-50.
User power (+) Voltage: Terminals C-43, C-45, C-47 and C-49
+V1 Terminals C-35, C-37, C-39 and C-41 are not used
NC
COM1 and COM2 are connected together in the module.
A
B
C
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15