Rockwell Automation 1746-NR8 SLC 500 RTD/Resistance Input Module User Manual - Manual (Page 12)

Publication 1746-UM003A-EN-P
1-2 Overview
Figure 1.1 Simplified RTD Module Circuit
Digital
Constant Current Source
RTD Module
Bac
kpl
an
e
Digital Data Digital Data
RTD
RTD
RTD
RTD
Sense
Sense
Sense
Sense
Return
Return
Return
Return
RTD 0
RTD 1
RTD 2
RTD 3
A/D
Conversion
Ic=0.25 or
1.0 mA
RTD
RTD
RTD
RTD
Sense
Sense
Sense
Sense
Return
Return
Return
Return
RTD 4
RTD 5
RTD 6
RTD 7
µP Circuit