National Instruments SCXI Series Getting Started

Chapter 4 Connecting and Using Accessories and Transducers
© National Instruments Corporation 4-11 Getting Started with SCXI
If your strain gauge is a quarter-bridge configuration, you still need to
enable the bridge-completion network, but you must also install a
dummy resistor with resistance equal to that of the strain gauge at no load.
If you have a full-bridge configuration, you do not need to enable the
bridge-completion network. In all configurations, however, you must still
use excitation. Figures 4-5, 4-6, and 4-7 show a number of possible bridge
configurations in which V
EX
,R
1
, and R
2
are on the SCXI-1121 module. To
determine which of the following bridge configurations your strain gauge
uses, refer to your strain gauge manufacturer manual.
Note
The following acronyms and symbols apply to Figures 4-5 through 4-7:
ε =strain
GF = Gauge Factor
ν = Poisson's Ratio
V
r
=[V
IN
/V
EX
) Strained – (V
IN
/V
EX
) Unstrained]
R
L
= Line Resistance
R
g
= Gauge Resistance
•
= Connection to Terminal Block

National Instruments SCXI Series Specifications

General

Brand	National Instruments
Model	SCXI Series
Category	Control Unit
Language	English