Yokogawa Integral Oxygen Analyzer ZR202 - Manual (Page 104)

<9. Calibration>
9-3
IM 11M12A01-04E
21.0 p1 p2 0.51
81.92
ez
e2
e1
es
0
C
A B
Zero correction ratio = (B/A) x 100 (%) Correctable range: 100 ± 30%
Span correction ratio = (C/A) x 100 (%) Correctable range: 0 ± 18%
Cell
electromotive
force, mV
Calibration curve
before correction
Corrected calibration
curve (theoretical
calibration curve)
Zero origin
Span gas concentration Zero gas concentration
Span origin
Oxygen concentration (vol%O
2
)
F9.2E.ai
Figure 9.2 Calculation of a Two-point Calibration Curve and Correction Ratios Using
Zero and Span Gases
Figure 9.3 shows a one-point calibration using only a span gas. In this case, only the cell
electromotive force for a span gas with oxygen concentration p1 is measured. The cell electromotive
force for the zero gas is carried over from a previous measurement to obtain the calibration curve. The
principle of calibration using only a span gas also applies to the one-point calibration method using a
zero gas only.
21.0 p1 0.51
81.92
ez
e1
es
0
C
A B
Zero correction ratio = (B/A) x 100 (%) Correctable range: 100 ± 30%
Span correction ratio = (C/A) x 100 (%) Correctable range: 0 ± 18%
Cell
electromotive
force, mV
Calibration curve before
correction
Previous
zero gas data
Corrected calibration curve
(theoretical calibration curve)
Zero origin
Span origin
Span gas concentration
Oxygen concentration (vol%O
2
)
F9.3E.ai
Figure 9.3 Calculation of a One-point Calibration Curve and Correction Ratios Using a
Span Gas