Teledyne API Model 200AH NOX Analyzer Instruction Manual, 06492, Rev. G2
4-5
4.2. Operation Summary

4.2.1. NOX Sensor Module, Reaction Cell, Detector

The sensor module is where light from the chemilumenescent reaction is generated and detected.
It is the most complicated and critical sub-assembly in the entire analyzer. It consists of the
following assemblies and functions:
1. The reaction cell and ozone flow control module
2. Reaction cell heater/thermistor
3. PMT and High Voltage Power Supply
4. PMT cooler/cold block/heatsink/fan
5. Preamp assembly:
A. Preamp range control hardware
B. HVPS control
C. PMT cooler temp control
D. Electric test electronics
E. Optic test electronics

4.2.2. Oxygen Sensor Module (Option)

The main components of Oxygen Sensor are:
1. The transducer body consists of the paramagnetic cell and the magnet frame.
The interior of the paramagnetic cell is the only sample wetted surface. It is a precision
machined component containing the suspension assembly, and is secured within the magnet
frame.
2. Optical Assembly and Electronics Control PCB.
The optical assembly consists of a precision machined optical mounting bracket onto which
the integrated electronics board and the small photo-sensor board are fitted. The optical
assembly is secured to the magnet frame.
The electronics board contains the LED source, temperature compensation thermistors and
all other associated signal processing components, including a 16-way DC connector and the
multi-turn zero and span potentiometers.