Teledyne 326, 327 and 328 - Oxygen analyzers - Manual (Page 7)

1-1 Teledyne Analytical Instruments
Introduction Introduction Introduction Introduction Introduction Model 326/327/328 Model 326/327/328 Model 326/327/328 Model 326/327/328 Model 326/327/328
Introduction
The Teledyne Analytical Instruments (TAI) Model 326 series (Models
326, 327, and 328) analyzers use a unique Micro-Fuel Cell to measure the
concentration of oxygen in a gas stream. The analyzer can be housed in a
compact equipment case, a 19-inch rack mount unit, an explosion-proof
bulkhead-mounted enclosure, or separately from the panel-mounted control
unit.
The Micro-Fuel Cell (U.S. Patent No. 3,429,796) is a maintenance-free,
disposable, solid-state unit whose performance and usable life are guaran-
teed by TAI. The cell consumes oxygen from the gas around it and gener-
ates a proportional microampere current. The low level signal is then ampli-
fied by a solid-state, integrated circuit (IC) amplifier. The resulting DC
signal drives a temperature compensation circuit for the cell, and an integral
meter. The output signal is available at the analyzers terminal strip and is
linear over the specified ranges of analysis. It is suitable for driving a high-
impedance recording device.
The Micro-Fuel Cell responds accurately to the presence of oxygen,
regardless of flowrate. The measuring cell does not generate an output
current unless oxygen is present in the sample gas. Therefore, the instru-
ment has an absolute zero, and no zero gas is required to standardize the
analyzer. The analyzer can be calibrated using atmospheric air as a span
gas, providing one of the three ranges of analysis encompasses the oxygen
content of air.
The Model 326 series analyzers have three standard ranges: 0–5 % O
2
,
0=10 % O
2
, and 0–25 % O
2
.
In some instances an outer enclosure may contain the analyzer and other
related devices, such as sample system components or other analyzers.
These special designs are supported by special drawings included with the
standard drawings at the rear of the instruction manual. Use those drawings
in conjunction with the standard drawings, and note any differences.
Specific models in the 326 series are described in the following para-
graphs. Be sure to read the description of the model you have purchased.