Campbell CR3000 Micrologger, Руководство оператора

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Section 8. Operation
370
Resistive-Bridge Circuits with Current Excitation
1
Resistive-Bridge Type and
Circuit Diagram
CRBasic Instruction and
Fundamental Relationship
Relational Formulas
Four-Wire Resistance
2
CRBasic instruction: Resistance().
Fundamental relationship
3
:
Full Bridge
2
CRBasic Instruction: Resistance()
Fundamental relationship
3
:
1
See Current Excitation Cabling
(p. 421)
for precautions to consider when measuring resistances > 1000 Ω or
sensors with leads > 50 feet.
2
Key: I
x
= excitation current; IxR = Current Return; V
1
= sensor return voltage; R
s
= "variable" o
r "sensing"
resistor.
3
Where X = result of the CRBasic bridge measurement instruction with a multiplier of 1 and an offset of 0.