Sensornet ORYX DTS, User Manual

Page: 64 / 101

Page 58 Oryx DTS User Manual v4
Leaving the differential correction method set as ‘single-ended’, click ‘Next’.
Temperature Slope Calibration
Three methods of setting the slope correction are provided:
•
Fixed value
•
Matched sections
•
Temperature reference sections
Each of these is described below.
Slope Calibration – Fixed Value
In this case the user manually adjusts the slope calibration value to obtain the
correct slope of the temperature trace. This is easily done for fibre at constant
temperature along its length but can also be done if two sections of fibre are known
to be at the same temperature. This works best if the two sections are widely
separated from each other. The graphical display will update ‘live’ as the slope
value is adjusted using the slide control or the numerical value is modified. See
Figure 40.
NOTE: The absolute value, or offset, of the temperature trace does not need to be
correct at this stage. This is corrected for in the next section:- Offset correction.
The user should zoom into the temperature trace to an appropriate scale. The
original temperature trace is shown in grey and the trace calculated with the new
slope setting, is shown in white.