Teledyne 3000TA-XLEU - Trace oxygen analyzer - Manual (Page 27)

Trace Oxygen Analyzer Operational Theory
Teledyne Analytical Instruments 11
directly proportional to the concentration of oxygen in the gaseous
mixture. In other words it has a linear characteristic curve, as shown in
Figure 2-3. Measuring circuits do not have to compensate for
nonlinearities.
In addition, since there is zero output in the absence of oxygen, the
characteristic curve has close to an absolute zero (less than ± 0.2 ppm
oxygen). This means there is usually no need to zero calibrate the
instrument. Depending upon the application, zeroing may still be used
to compensate for the combined zero offsets of the cell and the
electronics.
Figure 2-3: Characteristic Input/Output Curve for a Micro-Fuel Cell