Geosignal XP 101K USB, Руководство пользователя

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The datapoints not following the line should be discarded.
To calculate the Instrument offset (to be programmed into the
control file) use the following formula:
(0.039 / FS) * 65536 = 148
FS is the full scale: 17.236 Bar in this case (as show by
CALIBRAT.TXT)
Note: 65536 = 2^16bit
.
Calculating the Scale Constant requires us to calculate the ratio
between the ideal slope and the current one.
Calibration should be done at about ¾ of the FS of the
instrument with a reference pressure (after the instrument has
been programmed with the correct offset).
The correct slope should be 1.000 (Reference pressure / Read
pressure).
A ratio of 1.000 indicates: no need of scale calibration; a ratio
smaller than 1.000 indicates that the gain needs to be lowered; a
ratio greater than 1.000 indicates that the gain needs to be
increased.
For Example: analysing some datapoints the ratio between
reference pressure / read pressure works out as 0.99684.
To calculate the Instrument scale (to be programmed into the
control file) use the following formula:
ratio * 32768 -32768 = offset → 0.99684 * 32768 -32768 = -104
Note: 32768 = 2^16bit / 2
If the instrument is set to operate in Psi the calculation does not
change, just replace FS with the Psi FS value (249.99) in this
case as 249.99 Psi = 17.236 Bar. There is no need to recalibrate
nor change offset and scale values when switching between
measurement units (between Psi, Bar).
Geosignal XP 101K USB Data Logger
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www.geosignal.com.au
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