Campbell CR300 series, Operator'S Manual

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CR300-Series Datalogger
29
TABLE 6-1. Resistive-Bridge Circuits with Voltage Excitation
Resistive-Bridge Type and
Circuit Diagram
CRBasic Instruction and
Fundamental Relationship
Three-Wire Half-Bridge
1,3
CRBasic Instruction: BrHalf3W()
Fundamental Relationship 2 :
𝑋𝑋 =
2 𝑉𝑉
2
− 𝑉𝑉
1
𝑉𝑉
𝑋𝑋
− 𝑉𝑉
1
=
𝑅𝑅
𝑠𝑠
𝑅𝑅
𝑓𝑓
Four-Wire Half-Bridge
1,3
CRBasic Instruction:
BrHalf4W()
Fundamental Relationship 2 :
𝑋𝑋 =
𝑉𝑉
2
𝑉𝑉
1
=
𝑅𝑅
𝑠𝑠
𝑅𝑅
𝑓𝑓
Full-Bridge
1,3
CRBasic Instruction: BrFull()
Fundamental Relationship
2
:
𝑋𝑋 = 1000 ∙
𝑉𝑉
1
𝑉𝑉
𝑋𝑋
= 1000 �
𝑅𝑅
3
𝑅𝑅
3
+ 𝑅𝑅
4
−
𝑅𝑅
2
𝑅𝑅
1
+ 𝑅𝑅
2
�