Teledyne 6750 operating instructions Electronic Signal Processing, Display and Control

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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

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Contents Model Teledyne Analytical InstrumentsModel Copyright 2005 Teledyne Instruments/ Analytical InstrumentsSpecific Model Information Total Organic Carbon AnalyzerSafety Messages Total Organic Carbon Analyzer Table of Contents Setup and Operation MaintenanceAppendix Index Teledyne Analytical InstrumentsList of Figures Model 6750 TOC Analyzer Front door removedDC Power Supply Module List of Tables Combustible GAS Usage Main Features of the Analyzer IntroductionTotal Organic Carbon Analyzer Introduction Intended Use of the Analyzer OptionsTypical Applications Introduction ModelOperator Interface Model 6750 TOC Analyzer Front door removedIntroduction Model Teledyne Analytical Instruments Background Theory of OperationOverview Total Organic Carbon Analyzer Theory of OperationTheory of Operation Model Npoc or TOC Direct MethodConclusion TOC Measurement Basics UV/Heated Persulfate Method of Analysis Comparison of TOC Measurement Technologies Subsystems Principles of Operation Sample HandlingSample Handling for TOC -Direct Sample Handling TOC-True TOC analysis in a continuous, on-line TOC analyzer Inorganic Carbon Removal/AnalysisRelationship Between TIC and pH OxidationOxidation Reactions Ndir CO2 Gas Detection 10 Model 6750 Ndir UnitElectronic Signal Processing, Display and Control BENCHMARK/AUTO-VALIDATION Theory of Operation Model Teledyne Analytical Instruments Unpacking the Analyzer InstallationTotal Organic Carbon Analyzer Installation Mounting the AnalyzerInstallation Model Analyzer DimensionsPower Connection Electrical ConnectionsAnalog Outputs Electrical Connections to the Model4 RS-232 Serial Connection Alarm ConnectionsGas/liquid Connections Liquid ConnectionsGas and Liquid Connections to the Analyzer Gas ConnectionsChecking the System Gas Carrier ConnectionsInstallation Model Teledyne Analytical Instruments Setup and Operation Total Organic Carbon Analyzer Setup and OperationAnalyzer Startup Setup and Operation Model Drain ConnectionsRun Mode MenusParameter Menu Alarm Settings Stream Sequencer 5 D/DBPR Detailed Calibration Procedures Methanol 100 mg/Liter 1000 mg/LiterEthylene Glycol EthanolPreparation of Phosphoric Acid Solution Total Organic Carbon Analyzer Setup and Operation Operation RUN ScreenShutdown Historical DataSetup and Operation Model Maintenance Compupter-aided TestingTotal Organic Carbon Analyzer Maintenance Troubleshooting Maintenance ModelModule Service Ndir Gas CalibrationIR Calibration Installing Calibration Adapter Ndir ServiceRemoving the Ndir Unit P/N ST36000 Total Organic Carbon Analyzer Maintenance Maintenance Model To Reassemble Use alternate tightening sequence Master Interface Board P/N ST13042-1 Removing the Master Interface Board4 D. C. Power Supply DC Power Supply ModuleCE Computer P/N Replacing CE ComputerUV Lamp Replacement UV Lamp P/N ST20009UV Reactor Assembly P/N ST20003-1 Removing the UV Reactor AssemblyUV Power Supply 10 Removing the UV Power Supply Mass Flow Controller P/N ST18001A11 Mass Flow Controller Metering Valve P/N ST1605012 Metering Valve Sparger P/N ST2002513 Sparger Pumps Maintenance Model 14 Removing the Pump Maintenance Model 13 4-20 mA Adjustment Procedure System DiagnosticsSetting 100 MV Control Voltage 1Specifications AppendixTotal Organic Carbon Analyzer Appendix Appendix Model Sample requirementsParts Listing Description ImageAppendix Model Total Organic Carbon Analyzer Appendix Appendix Model Total Organic Carbon Analyzer Appendix Option Auto CALTrue Dual Range Option not an electronic scaling Dbpr OptionAppendix Model AS-BUILT Drawings Appendix Model Teledyne Analytical Instruments Index Total Organic Carbon Analyzer IndexIndex Model ModbusPump mounting screw Index Model