Teledyne operating instructions Ndir CO2 Gas Detection, Model 6750 Ndir Unit

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Total Organic Carbon Analyzer	Theory of Operation

2.4.4 NDIR CO2 Gas Detection

The key component for reliable TOC analysis is the precise and interference-free detection of CO2. The Model 6750 NDIR unit requires very little maintenance because of its ability to handle the corrosive gases generated in TOC analysis. This is due in part to its non-reflective borosilicate sample cell. It has no moving parts which further reduces the maintenance load and it uses an internal self-calibrating technique.

The NDIR unit is shown in Figure 2-10. Some of the features of the NDIR unit are as follows:

•Specific, interference-free CO2 detection

•Dual-wavelength rationing compensates for drift

•Computer-controlled for accuracy

•Sapphire protected optics

•Non-corrosive, non-reflective sample cell (borosilicate)

•No moving parts or tools required for easy maintenance and service

•No critical realignment required

Figure 2-10: Model 6750 NDIR Unit

The NDIR CO2 detector uses a completely solid state, dual wavelength ratioing technique with a single borosilicate sample cell that

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Contents Teledyne Analytical Instruments ModelCopyright 2005 Teledyne Instruments/ Analytical Instruments ModelTotal Organic Carbon Analyzer Specific Model InformationSafety Messages Total Organic Carbon Analyzer Table of Contents Maintenance Setup and OperationIndex Teledyne Analytical Instruments AppendixModel 6750 TOC Analyzer Front door removed List of FiguresDC Power Supply Module List of Tables Combustible GAS Usage Total Organic Carbon Analyzer Introduction Main Features of the AnalyzerIntroduction Typical Applications OptionsIntended Use of the Analyzer Introduction ModelModel 6750 TOC Analyzer Front door removed Operator InterfaceIntroduction Model Teledyne Analytical Instruments Overview Theory of OperationBackground Total Organic Carbon Analyzer Theory of OperationNpoc or TOC Direct Method Theory of Operation ModelConclusion TOC Measurement Basics UV/Heated Persulfate Method of Analysis Comparison of TOC Measurement Technologies Sample Handling Subsystems Principles of OperationSample Handling for TOC -Direct Sample Handling TOC-True Inorganic Carbon Removal/Analysis TOC analysis in a continuous, on-line TOC analyzerOxidation Relationship Between TIC and pHOxidation Reactions 10 Model 6750 Ndir Unit Ndir CO2 Gas DetectionElectronic Signal Processing, Display and Control BENCHMARK/AUTO-VALIDATION Theory of Operation Model Teledyne Analytical Instruments Total Organic Carbon Analyzer Installation InstallationUnpacking the Analyzer Mounting the AnalyzerAnalyzer Dimensions Installation ModelElectrical Connections Power ConnectionElectrical Connections to the Model Analog OutputsGas/liquid Connections Alarm Connections4 RS-232 Serial Connection Liquid ConnectionsGas Connections Gas and Liquid Connections to the AnalyzerGas Carrier Connections Checking the SystemInstallation Model Teledyne Analytical Instruments Analyzer Startup Setup and OperationTotal Organic Carbon Analyzer Setup and Operation Drain Connections Setup and Operation ModelMenus Run ModeParameter Menu Alarm Settings Stream Sequencer 5 D/DBPR Detailed Calibration Procedures Ethylene Glycol 100 mg/Liter 1000 mg/LiterMethanol EthanolPreparation of Phosphoric Acid Solution Total Organic Carbon Analyzer Setup and Operation RUN Screen OperationHistorical Data ShutdownSetup and Operation Model Total Organic Carbon Analyzer Maintenance MaintenanceCompupter-aided Testing Maintenance Model TroubleshootingNdir Gas Calibration Module ServiceIR Calibration Ndir Service Installing Calibration AdapterRemoving the Ndir Unit P/N ST36000 Total Organic Carbon Analyzer Maintenance Maintenance Model To Reassemble Use alternate tightening sequence Removing the Master Interface Board Master Interface Board P/N ST13042-1DC Power Supply Module 4 D. C. Power SupplyReplacing CE Computer CE Computer P/NUV Lamp P/N ST20009 UV Lamp ReplacementRemoving the UV Reactor Assembly UV Reactor Assembly P/N ST20003-1UV Power Supply Mass Flow Controller P/N ST18001A 10 Removing the UV Power SupplyMetering Valve P/N ST16050 11 Mass Flow ControllerSparger P/N ST20025 12 Metering Valve13 Sparger Pumps Maintenance Model 14 Removing the Pump Maintenance Model System Diagnostics 13 4-20 mA Adjustment ProcedureSetting 100 MV Control Voltage Total Organic Carbon Analyzer Appendix 1SpecificationsAppendix Sample requirements Appendix ModelDescription Image Parts ListingAppendix Model Total Organic Carbon Analyzer Appendix Appendix Model Total Organic Carbon Analyzer Appendix Auto CAL OptionDbpr Option True Dual Range Option not an electronic scalingAppendix Model AS-BUILT Drawings Appendix Model Teledyne Analytical Instruments Total Organic Carbon Analyzer Index IndexModbus Index ModelPump mounting screw Index Model