Calibration
The data logger allows two point calibration of its pressure sensor and
a 'seconds per week' calibration of the internal quartz clock.
Calibration is done by editing and saving the parameters SENSOR or
CLOCK of the file CONTROL.TXT
CLOCK: +012
for example will add approx 12 seconds per week on
a slow clock, it is possible to add up to 127 seconds or to detract -128.
Offset and scale Calibration:
The datalogger stores the raw data into the memory separated from
the calibration constants, then during file access the raw data is
converted into a more readable text/csv file.
If the offset and scale values are changed the contents of the file will
also change.
Although small negative pressure values can be shown because of
calculation and errors the logger cannot measure negative values
(depression).
To compensate for zero and gain errors XP 101K can be
programmed with the following:
The offset calibration compensates for any zero pressure offset errors:
SENSOR:000.00 Off+0001
set the offset calibration: add input x
FS x offset (0001) x 0.0000152, this will increase or decrease the
raw output of the sensor up to +15% of FS
(000.00 Off+9830)
and down to -15% of FS
(000.00 Off-9830)
in order to
compensate for any offset errors.
The offset compensation is always added to the measures.
The Scale calibration compensates for any pressure gain errors:
SENSOR: 000.00 Sca+0001
set the scale calibration: add input x
FS x scale (0001) x 0.0000305, this will increase or decrease the gain
on the sensor up to about +30% of FS
(000.00 Sca+9830)
and
Geosignal XP 101K USB Data Logger
Copyright 2017-2018 all rights reserved
www.geosignal.com.au
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