Campbell Scientific CS431 Submersible Pressure Transducer - Manual (Page 16)

CS431 Submersible Pressure Transducer
5.2.1.3 Example CR10X P ROGRAM – High Precision Measurement for 5 PSI Sensors
The Standard and Enhanced Measurement Programming Examples (see
Section 5.2.1.1) result in a resolution of ±0.2 inches. These methods use the 25
mV Slow Range of the CR10X. This level of resolution is acceptable for many
measurement needs. However, in the 0 – 5 PSI range, greater resolution is
often needed.
Using the High Precision Measurement Programming Example (below) will
result in a resolution of ±0.03 inches. This uses the 7.5 mV Slow Range of the
CR10X.
In the example below:
Vr = differential voltage at diff channel 1
Vo = differential voltage at diff channel 2
L = pressure measurement in nominal units
P = pressure measurement in psi units using provided calibration values m
and b from calibration data sheet for the specific sensor being used
T = temperature measurement in degrees C
1: Ex-Del-Diff (P8)
1: 1
Reps
2: 3 25 mV Slow Range
3: 1 DIFF Channel
4: 1 Excite all reps w/Exchan 1
5: 1 Delay (units 0.01 sec)
6: 800 mV Excitation
7: 1 Loc [ Vr ]
8: 1.0 Mult
9: 0.0 Offset
2: Ex-Del-Diff (P8)
1: 1
Reps
2: 2 7.5 mV Slow Range
3: 2 DIFF Channel
4: 1 Excite all reps w/Exchan 1
5: 1 Delay (units 0.01 sec)
6: 800 mV Excitation
7: 2 Loc [ Vo ]
8: 1.0 Mult
9: 0.0 Offset
; Calculate L factor
L=100*(Vo/Vr)
; Measure Temperature
3: Temp (107) (P11)
1: 1
Reps
2: 5 SE Channel
3: 2 Excite all reps w/E2
4: 4 Loc [ T ]
5: 1.0 Mult
6: 0.0 Offset (cont.)
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