Rockwell Automation 1771-IND series C INSTL INSTR AC/DC INPUT MODULE - Manual (Page 9)

Digital ac/dc (24V) Input Module 9
Publication 1771-IN052B-EN-P - April 2006
You can also use an output module (cat. no. 1771-ON) to directly drive terminals on an ac/dc
(24V) input module (cat. no. 1771-IND/C), but you must use a 470
Ω, 3 W resistor between
the output terminal and L2 (common) as shown below.
Use the same ac power source to power both modules to ensure proper phasing and prevent
module damage.
L1
24V ac High
L2
ac Low
ac (24V)
Output Module
( (cat. no. 1771-OND)
ac/dc (24V)
Input Module
(cat. no. 1771-IND/C)
L2
10427-I
(cat. no. 1771-ON)
L2
ac Low
470 Ω, 3 W
Resistor
ac (24V)
Output Module
ac/dc (24V)
Input Module
(cat. no. 1771-IND/C)
L2
24V ac High
10428-I
L1
Driving a 1771-IND/C Module with a 1771-OND Module Driving an Input Module with an Output Module