SCC-SG Series Strain-Gauge Modules User Guide
14
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Quarter-Bridge Type II
This section provides information for the quarter-bridge strain-gauge
configuration type II. The quarter-bridge type II measures either axial or
bending strain.
Note
The quarter-bridge temperature-compensating element (dummy gauge) adds an
additional strain-gauge element to the quarter-bridge type II that is not present in the
quarter-bridge type I. You must use the half-bridge completion on the SCC-SG03 for the
quarter-bridge type II to function properly.
Figure 4 shows a general quarter-bridge type II circuit diagram.
Figure 9.
Quarter-Bridge Type II Circuit Diagram
The following symbols apply to the circuit diagram and equations:
•
R
1
and R
2
are a half-bridge completion resistors.
•
R
3
is the quarter-bridge temperature-compensating element (dummy
gauge).
•
R
4
is the active element measuring tensile strain (+
ε
).
Figure 10 shows how to set up two quarter-bridge type II configurations
with the SCC-SG03. You connect a quarter-bridge type II to the SCC-SG03
the same way you connect a half-bridge configuration to the SCC-SG03.
R
1
R
L
R
2
R
L
R
L
R
3
+
–
V
EX
–
+
V
CH
R
4
(+ )
