Teledyne 3000ZA-3X Operational Theory, Introduction, ZrO2 Sensor, Principles of Operation

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Trace Oxygen Analyzer

Operational Theory

 

 

 

Operational Theory

2.1 Introduction

The analyzer is composed of three subsystems:

1.Three Zirconium Oxide (ZrO2) Sensors. Each one has a specific range of analysis: Low range sensor of 0-200 ppm, medium range sensor of 0-2 %, and high range sensor of 0-95%.

2.Sample System

3.Electronic Signal Processing, Display and Control

The sample system is designed to accept the sample gas and

transport it through the analyzer without contaminating or altering the sample prior to analysis. The ZrO2 sensor is a device that translates the amount of oxygen present in the sample into an electrical current. The electronic signal processing, display and control subsystem simplifies operation of the analyzer and accurately processes the sampled data. The microprocessor controls all signal processing, input/output and display functions for the analyzer.

2.2 ZrO2 Sensor

2.2.1 Principles of Operation

Teledyne’s zirconium oxide sensor is a miniature solid state sensor. It uses a stabilized zirconia disc as an electrolyte with a sensing electrode (the cathode) and a counter electrode (the anode) on each side of the disc. The zirconia is heated to a temperature of about 500°C via a built-in heater. By applying a suitable reference voltage (approximately

0.75volt) across the cathode and anode, the heated zirconia acts as an electrolyte which is capable of moving oxygen ions within its crystalline structure. This allows for the reduction of oxygen molecules reaching the cathode and the generation of a current equivalent to the parts per million oxygen in the sample gas.

 

 

 

Teledyne Analytical Instruments

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Contents Model 3000ZA-3X 3000ZA-3X Specific Model Information Important Notice Safety Messages 3000ZA-3X Vii Table of Contents Testing the System Appendix MaintenanceModel 3000ZA Rear Panel Model 3000ZA Front PanelXii List of TablesTypical Applications Main Features of the AnalyzerIntroduction OverviewIntroduction 3000ZA-3X Model DesignationsModel 3000ZA Front Panel Front Panel Operator InterfaceAlphanumeric Interface Screen Function KeysData Entry Keys Digital Meter DisplayRear Panel Equipment Interface Access DoorStandby Button Optional ∙ 50-Pin Equipment Interface PortPrinciples of Operation Operational TheoryIntroduction ZrO2 SensorOperational Theory 3000ZA-3X Sample SystemZirconium Oxide Sensor Application Notes Electronics and Signal ProcessingOperational Theory 3000ZA-3X Component Location Electronic Block Diagram Unpacking the Analyzer InstallationMounting the Analyzer Installation 3000ZA-3X Gas Connections Rear Panel ConnectionsInstallation3000ZA-3X Electrical Connections Zero in and Span in OptionalEquipment Interface Connector Pin Arrangement Analog Output Connections Threshold AlarmAlarm Relay Contact Pins System AlarmRemote Calibration Connections Range ID Relay Connections Remote Probe Connections 2.3 RS-232 Port FET Series ResistanceCommands via RS-232 Input Testing the System Installing the Zirconium Oxide SensorsOperation Style Conventions Using the Data Entry and Function ButtonsKeys Description Escape EnterAnalyze Screen Menu/Screen StructureSystem Menu Hierarchy of Available Functions Enter New Password T a Password routineEnter Password T a Change PasswordModel Routine Logout RoutineSelf-Test Routine Analog-Out Adjust RoutineFilter Routine 20mA Gain 20mA Limit False Track in Cal Yes Span Menu Auto-Calibration TimerChange Stream Span Sensor Span TimerSpan Value Span Begin Begin Span? Span FinishSpan Auto Finish Span BeginZero Finish Zero MenuZero Value Zero Begin Begin Zero? Zero TimerZero Timer 7 min Zero BeginAL-1 NON-LATCHING AL-1 20.00 ppm AL-2 Active Alarms MenuAlarm Active Alarm PolarityAL-1 80.00 ppm Alarm FailsafeAlarm Latching Alarm SetpointRange Select Range MenuRange Select Auto Range Setpoints Manual Range SelectRemoving the Sensor MaintenanceRoutine Maintenance Sensor ReplacementMaintenance 3000ZA-3X Sensor Block with Middle Sensor Installed Fuse ReplacementSelf-Test Result Display System Self Diagnostic TestRear Panel Removal Remove only those screws marked with an Major Internal ComponentsTroubleshooting CleaningTrace Oxygen Analyzer Maintenance Maintenance 3000ZA-3X Teledyne Analytical Instruments Appendix SpecificationsOperating Temperature 5-35 C Qty Part Number Description Recommended 2-Year Spare Parts List19-inch Relay Rack Panel Mount Drawing ListFlow Rate Recommendations Application NotesRestriction Devices BY-PASS Conversions