Rockwell Automation 1746-NT8 SLC 500 Thermocouple/mV Analog Input Module User Manual - Manual (Page 17)

Publication 1746-UM022B-EN-P - January 2005
Module Overview 1-7
Linear Millivolt Device Compatibility
(1)
A large number of millivolt devices may be used with the 1746-NT8
module. For this reason we do not specify compatibility with any
particular device.
However, millivolt applications often use strain gage bridges. A
resistive voltage divider using fixed resistors is recommended for this
application. The circuit diagram below shows how this connection is
made.
(1) Output impedance of input device must be less than 100 ohm to meet accuracy specifications.
TIP
The resistors should be selected to ensure that the
differential input voltage is less than or equal to ±100
mV.
+
-
+ Voc
Strain
Gage
Bridge
Channel
Input
fixed
fixed fixed
variable
1746-NT8