Teledyne M5000B operating instructions Setup of the Logarithmic Amplifier, Inverting Amplifier

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5 Maintenance		Model 5000B Photometric Analyzer

7.After the peaks are balanced, adjust the gain control until the tallest of the two peaks is 8 to 9 volts. The peaks should still be within1 volt of each other.

8.It is always good practice to operate the analyzer with as low a gain as possible. Therefore,withthegaincontroljustbarelyoffitsstop, onceagainremove or add screens in the light path to obtain as high a voltage as possible without exceeding 9 volts for the highest peak. Read-just gain for 8 to 9 volts.

This concludes the balancing procedure and the instrument is ready for calibration.

5.5.6 Setup of the Logarithmic Amplifier

Theamplifierisinvertingandcontinuouslytakingthelogarithmoftheoutput signalofthesecondamplifier. Youcanobservetheoutputbyconnectingthescope probe to TP4.

The correct wave shape has a rounded negative going pulse that is the signal and a flat-topped positive pulse that depicts saturation of the log amplifier.

You should not permit distortions or oscillations in the rounded peaks.

When the positive going pulse is not flat or is distorted, adjust trimpot R3 only enough to obtain a flat positive pulse. If you over adjust, you may lose part of the second decade of absorption and affect the accuracy of analysis for high concentrations of the component of interest where the measuring pulse can become very short. The log amplifier saturates because the amplifier is incapableoftakingthelogarithmoftheslightlynegativebaseline.

5.5.7 Inverting Amplifier

Theamplifierisinvertingandhasagainof1. Itinvertstheoutputsignalofthe logarithmicamplifierandactsasabufferbetweenthelogarithmicamplifierandthe reedswitchandintegrators. Toobservethe outputoftheinverter,connectthescope probe to TP5. The wave must be a duplicateof that observed on TP4, except that itisinverted.

5-6: Part II

Teledyne Analytical Instruments

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Contents Photometric Analyzer Teledyne Analytical InstrumentsModel 5000B Copyright 1999 Teledyne Analytical InstrumentsTable of Contents IiiModel 5000B Teledyne Analytical Instruments Part I Part I Control UnitInstallation Ii PartOperation Maintenance Iv Part Model 5000B Photometric AnalyzerOverview Typical ApplicationsPhotometric Analyzer Part I Control Unit Introduction Model 5000B Other NIR Absorbers that can be measured consult factory Introduction Model 5000B Main Features of the Analyzer 1 UP/DOWN Switch ESCAPE/ENTER SwitchOperator Interface Model 5000B Controls, Indicators, and Connectors Control Section Interface Panel Model 5000B Interface Panel Introduction Model 5000B Installation Unpacking the Control/Analysis UnitPart Primary Input Power Connections 115VACExamples Analog Output ConnectionsAlarm Relays Range Voltage Current mATypes of Relay Contacts The connectors are Part I RS-232 Signals RS-232 Sig RS-232 Pin PurposeTesting the System Command DescriptionParameter Setting Part Operation Photometric Analyzer Operation /Control UnitOperation/Control Unit Hierarchy of System Functions and Subfunctions Setting up an AUTO-CAL System FunctionSelect More and press the Enter Key PasswordProtection Entering the PasswordInstalling or Changing the Password Logging Out System Self-Diagnostic Test Model Screen CheckingLinearitywithALGORITHMDigital Filter Setup Setting 90% Response time secondsFilter or Solenoid Setup Hold/Track Setup Calibration/Hold Timer SetupCalbrt hold 3 min Sample hold 1 min Analog 4 to 20 mA Output CalibrationUse UP/DOWN arrow to Adjust 4 ma 250 ModelAuto Mode Zeroing Show NegativeZero Cal Manual Mode Zeroing Cell Failure SccmAuto Mode Spanning Manual Mode SpanningSpan Cal How to access the offset function Offset FunctionSelect zero mode Auto Select zero mode MAN Zero off 0.0 ppm ENT to begin ZeroAlarms Function AL1 1ØØØ ppm HI DftN FsN LtchN Range Select Function Manual Select/Define Range ScreenAuto Screen Precautions 2illustratestheseschemesgraphically Analyze Function Set Range Screen Algorithm Application More Curve Algorithm Screen Auto Mode Linearization Fuse Replacement Part I Control Unit/Analysis Unit MaintenanceSystem Self Diagnostic Test Maintenance Model 5000B Photometric AnalyzerPower AnalogPreamp Cell detectorPart Part II Part II Analysis UnitRoutine Maintenance Part II Analysis Unit Appendix Iv Part Operations/Analysis Unit Control Functions Explosion-ProofVersionControlModuleControl Settings Start-pPreliminaryInspection Analyzers not equipped with Auto ZeroPower On Observations Pre-Start-upElectricalCheckoutTeledyneAnalyticalInstruments4-5 Procedure CalibrationStandardizationFluids TeledyneAnalyticalInstruments4-7 Operations/Analysis Unit TeledyneAnalyticalInstruments4-9 Operations/Analysis Unit TeledyneAnalyticalInstruments4-11 Operations/Analysis Unit TeledyneAnalyticalInstruments4-13 Ppm simulated water using Span Zero SampleAttachment 5000B/5020 NIR Analyzer Operations/Analysis Unit Operational Theory Contd Source Module OpticalSystem Sample cellAnalyzerSystem-BlockDiagram Power Module Block Diagram Detectorcompartment Routine Maintenance Part II Maintenance/Analysis UnitSystem Visual Check and Response Procedure Automatic operation and routine operational dutiesSuggested Preventive Maintenance Schedule DailyEquipment Required Oscilloscope Display of the I to E Converter Output Part II Maintenance/Analysis Unit Setup of the Logarithmic Amplifier Inverting AmplifierBattery-Powered Oscilloscope Synchronization Point Interface Board Terminals StripPart Part II Maintenance/Analysis Unit Part Specifications Operating Temperature 0-50oCPhotometric Analyzer, 5000B Appendix Appendix Models 5000B Other Features Recommended 2-Year Spare Parts List QtyP/NDescriptionDrawing List, 5000B Appendix Models 5000B Teledyne Analytical Instruments