SCC-SG Series Strain-Gauge Modules User Guide
8
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3.
Insert the wires into the screw terminals.
4.
Tighten the screws to 0.5–0.6 N · m (4.4–5.3 lb · in.) of torque with a
flathead screwdriver.
Each screw terminal on the SCC-SG0
X
and SCC-SG24 is labeled by pin
number <1..6>. The input stage of the SCC-SG0
X
and SCC-SG24 provides
two differential analog input channels for measuring strain. The input pins
to the SCC-SG0
X
and SCC-SG24 differ for each module. Pin 4 is a
single-ended channel routed to DAQ device channel
X
+8, and pin 6 is a
single-ended channel routed to DAQ device channel
X
. The value of
X
is
0 to 7 depending on the socket where you plug in the SCC-SG0
X
and
SCC-SG24, J(
X
+1) or J(
X
+9).
Panelettes
If you have an SCC carrier with configurable connectors, you can install
connectivity and interface panelettes to customize the SCC system.
Panelettes simplify signal connection to the SCC modules and eliminate the
need to rewire signals to the screw terminals when you change the signal
source.
The most common panelettes used with the SCC-SG0X and SCC-SG24
strain applications are the 9-pin D-Subminiature (DSUB), MIL-Spec, and
LEMO (B-Series).
SCC-SG0
X
and SCC-SG24
The various bridge configurations discussed in the
section
require different SCC modules. The following sections discuss the bridge
configuration types supported by each module, and provide connection and
electrical diagrams for the different bridge configurations.
Variable Definitions
In the following figures, the variables are defined as:
ε
is the measured strain (+
ε
is tensile strain and -
ε
is compressive strain).
ν
is the Poisson’s ratio, defined as the negative ratio of transverse strain to
axial (longitudinal) strain.
V
CH
is the measured voltage of the signal.
V
EX
is the excitation voltage.
