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3.8 Calibration Panel
The Calibration panel is used for calibrating the AccuLase-GPA™ for both zero and span. It is shown in
Figure 13: Calibration Panel
The first four fields on the Calibration panel indicate the analyzer’s calibration parameters. These
parameters are described in Table 5.
Table 5: Calibration Parameters
Parameter
Explanation
Raw Zero Reading
The analyzer’s concentration reading prior to calibration, in ppm, when analyzing
zero gas. For hydrogen sulfide analysis, the zero gas should be pure methane.
Raw Span Reading
The analyzer’s concentration reading prior to calibration, in ppm, when analyzing
calibration span gas. For hydrogen sulfide analysis, the span calibration gas
should be hydrogen sulfide of a concentration 50-100% of the analyzer’s full-
scale concentration in a balance of methane.
Response Factor
Offset
The y-intercept on a graph that places the raw concentrations at zero and span
on the x-axis and the true concentrations on the y-axis.
Response Factor
Slope
The slope of the calibration plot that plots raw concentrations at zero and span
on the x-axis and the true concentrations on the y-axis.
When calibration is performed, the analyzer takes the raw readings and stores them in memory. Once a
raw reading is obtained for both zero and span, the analyzer will then calculate the slope and offset for
the calibration curve by plotting the raw readings on the x-axis and the true readings on the y-axis. An
example of a calibration curve for the AccuLase-GPA™ is shown in Figure 22.
