Geokon 1133911, Instruction Manual

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3. Use temperature values and the linear gage factors shown on the six calibration
sheets in an Excel spreadsheet to develop a polynomial that describes how the gage
factor, G, varies with the temperature. (This polynomial will be supplied along with the
cal sheets).
Fourth, Using these developed polynomials calculated values of R0 and G at the
measured temperature, T, and with the current reading R1 find the pressure P from the
equation P = (R1- R0) G
An example follows. From the one Model 4700 temperature calibration sheet, and the
five pressure calibration sheets at five different temperatures. Using an Excel
Spreadsheet and the Chart Wizard Trendlines.
T = 3.7511E-07 R
T
2
+ 0.03484 R
T
-124.98
Equation 1
R0 = -0.00193T
2
+ 1.885T + 8367
Equation 2
G = -8.61E-11T
2
– 2.038E-09T - 0,0002246
Equation 3
For example: suppose that the reading, R
T
, on the temperature sensor is 8400 and the
reading on the pressure transducer, R1, is 6500,
then: from Equation 1 T = 194.1°C
and from Equation 2 R0 = 8660
and from Equation 3 G = -0.0002282
From which P = (6500
– 8660) (-0.002282) = 0.493MPa