Teledyne 6750 operating instructions •Benchmark/Auto-Validation •Auto-Calibration

Theory of Operation Model 6750

requires no wall reflectivity and is completely resistant to corrosive gases. The NDIR unit requires no optical chopper motor or mechanical devices but utilizes a single flashing infrared source to optically “chop” the infrared (IR) beam, which equally irradiates CO2/reference detectors. Using a reference eliminates water vapor interference. The non- reflective, corrosive resistant sample cell removes the requirement for chemically removing acid gases prior to detection.

Automatic gain control (AGC) is employed during the reference/sample cycle to compensate for such factors as IR source deterioration, dirty optical windows, etc. When the AGC level reaches a predetermined threshold, an optics alarm is activated. Malfunctions of major NDIR components are detected and indicated as an alarm, providing “fail-safe” operation. Signal detection is completely synchronous and because of the differential ratioing technique, drift is virtually eliminated.

All critical optics are protected by sapphire windows. The NDIR optical bench can be easily disassembled and windows cleaned (rarely ever required) and reassembled within fifteen (15) minutes, without realignment or the use of any tools.

The benefit of this absolute measuring, dual line spectral differential analytical technique, is that it provides simple, direct measurement of all CO2 contributing factors (including background) for a true and accurate calibration, and precisely offsets these effects for very accurate TOC determinations.

2.4.5 Electronic Signal Processing, Display and Control

A true, industrialized Microsoft Windows™-CE Computer offers complete automatic control of the analyzer, including the following:

•Benchmark/Auto-Validation

•Auto-Calibration

•Auto-Cleaning

•On-Board Historical Data for up to one (1) year

•Paperless Chart Recorder

•Diagnostics

•Networking (RS-232C/485)

Teledyne Analytical Instruments 18