Teledyne 328 Instruction Manual page 15

Operational Theory Operational Theory Operational Theory
Operational Theory Operational Theory
The analysis is specific for oxygen; i.e., the measuring cell will not
generate an output current unless oxygen is present in the sample gas. Thus,
the instrument has an absolute zero, and no zero gas is required to operate
the analyzer.
The measuring cell has the ability to respond accurately to the presence
of oxygen irrespective of flowrate. TBE recommends using ambient air as a
span gas or, if that is not possible, using a known calibration gas of about
80% of the range of interest value.
The measuring cell (U.S. Pat. #3,429,796) is a solid-state maintenance-
free structure that carries a TBE guarantee for performance and usable life.
The cell consumes oxygen from the gas surrounding it and generates a
proportional microampere current. The low level signal is then amplified by
a solid-state operational amplifier, and the resulting DC signal is suitable for
driving a high impedance recording device, a temperature compensation
circuit for the cell, and an integral 0-100 µA meter. The output signal is
linear over the specified ranges of analysis.
Temperature compensation maintains a cell output accuracy of ±5% from 0
°C to 50 °C (32 °F to 125 °F) or ±2% of scale at any constant temperature
between the above extremes. Accuracy is limited only by the accuracy of the
recording or indicating device used with the analyzer.
The TBE 326 Series Oxygen Analyzers utilize a unique electrochemical
transducer whose features include:
1) Specificity for oxygen.
2) Maintenance-free operation.
3) Long calibration interval and life.
Operational Theory Operational Theory Operational Theory Operational Theory Operational Theory
2.1 Method of Analysis 2.1 Method of Analysis
2.1 Method of Analysis 2.1 Method of Analysis 2.1 Method of Analysis
2.2 Transduction and Temperature Compensation 2.2 Transduction and Temperature Compensation 2.2 Transduction and Temperature Compensation
2.2 Transduction and Temperature Compensation 2.2 Transduction and Temperature Compensation
Teledyne Analytical Instru-
ments
Model 326/327/328 Model 326/327/328 Model 326/327/328
Model 326/327/328 Model 326/327/328
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