View Statistics/Two-Point Calibration - RBR 1050 Series User Manual

View Statistics/Two-point calibration

The statistics of
recorded data may be
viewed using the
View statistics menu
item. This produces a
dialog box that shows
the mean and standard deviation of a sample of readings based on the display
cursor. Nominally, the sample is 100 readings before the cursor. The data set
used in the calculation of statistics is highlighted on the graph. The user may
change the number of readings used for the calculation by editing the 'Number of
readings' box.
When working with newly downloaded data or a '.hex' file, the 'Change data view'
button will show the raw voltage ratio reported by the logger and can be used as
an input for the determination of calibration coefficients.
This same window will allow two-point calibration of certain sensors. Sensors
currently supported are: depth in a TGR-1050-HT logger, pH and dissolved
oxygen measured by an Oxyguard sensor. When this window is selected for a
logger which is connected and which has the appropriate sensor, the window
changes to that shown below.
Oxyguard Dissolved Oxygen Sensor
The calibration procedure for an oxygen sensor that has resulted in this window
is as follows:
1. Set the logger into a logging mode;
2. Immerse the logger into a solution containing 0% oxygen for a sufficient
time;
3. Immerse the logger into a solution containing 100% oxygen for a sufficient
time;
4. Retrieve the data from the logger;
5. Open the View statistics/Two-point calibration window;
6. Select the dissolved oxygen channel using the display cursor;
7. Select the raw data view using the Change data view button;
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