Emerson NGA 2000 TO2 instruction manual Calibration Procedure, Gas Scale Factor

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Instruction Manual

760008-A September 2001

Model NGA 2000 TO2

a.Calibration Procedure

The TO2 analyzer module is fully factory calibrated prior to shipment using certified gas standards. If the analyzer is operated within its specified operating conditions, no regular calibration is required. The zero calibration is very stable and does not require checking more than once a year.

Gas Scale Factor

The Gas Scale Factor is used to correct for background gases other than nitrogen. When the background of the sample is

other than nitrogen, the diffusion rate of oxygen into the sensor changes. By cor- recting for the background difference, the diffusion change can be compensated in software. The GSF can be entered manu- ally or calculated automatically. Calcula- tion of the GSF requires the user to enter the sample gas composition. In most ap- plications, the GSF is not required. How- ever, some backgrounds exhibit significantly different diffusion character- istics versus nitrogen (such as helium or hydrogen) and the GSF may improve performance.

Set the Gas Scale Factor as follows:

3-14 Operation

Rosemount Analytical Inc. A Division of Emerson Process Management

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Contents Model NGA 2000 TO2 Essential Instructions Table of Contents Model NGA 2000 TO2System & Network I/O Module Controls Setup Material Safety Data SheetList of Illustrations Analyzer Module Interconnection with Instrument PlatformModel NGA 2000 TO2 Preface Intended USE Statement DefinitionsSafety Summary Model NGA 2000 TO2 Documentation CompliancesGlossary of Terms Softkeys SystemOverview Section Description and SpecificationsFeatures Typical ApplicationsTrace Oxygen Detector Coulometric Principle Trace Oxygen Analyzer Module Top View Sample SPECIFICATIONS1General PhysicalGas Connections Model NGA 2000 TO2 Electrolyte Section InstallationUnpacking Electrolyte AdditionGAS Overpressure GasesGAS Connections Sample FlowElectrical Connections Electrical Shock Hazard Leak TestSensor Damage Analyzer Module Interconnection with Instrument Platform Outline and Mounting Dimensions Back Panel Connections Operation Displays & Operating KeysMeasure Status… Channel Lock… MFG Data Analyzer basic controls calibration & setup…Menu Lines & Softkey Functionality Measure Back… Signal on mini-bargraphEntering & Changing Variables Display Status… Main… Channel BasicCal Measure Mode DisplayPpm O2 Module Manufacturing Data Displays LCDReset Abort Startup & InitializationMeasure Status… Back… Quick StartInitiate quick start Analyzer Channel Status Basic CONTROLS, Setup and StatusPower supply voltages… Measure Back… Display Status… Main… ChannelMain… Channel BasicCal Single Component DisplayDisplay Status… Select Status… Tags Off LCDReset Multi Component DisplayOperation Status Basic Controls and SetupRange number Range numberDisplay controls… Display ControlsBrightness and Contrast Brightness 70 %Analyzer module controls… Expert Controls and SetupAnalyzer and I/O, expert controls & setup… Measure Channel Back…Calibration Procedure Gas Scale FactorGas scale factor… Air background gas concentrationSpan Calibration Span gas 90.0 ppm Measure Status… Back…Concentration alarm setup… Measure Back… ClrAlm AlarmsAlarms… Alarm generation isReBegin / end of ranges… RangesRanges… Range Begin PpmLinearization Measurement Display ConfigurationMeasurement display configuration… Concentration measurement… Concentration MeasurementGas measurement units Gas concentration unitsClamp low PVA to Temperature compensation at span gasSensor model Ppm to mg/Nm3 conversion factorFlow lower limit 400 ml/min Flow MeasurementFlow measurement… Temperature measurement units Temperature MeasurementTemperature measurement… Measure Status… Back… 37.50 ppm System & Network I/O Module CON Trols SetupSystem & network I/O module controls… System SIO module…Analog output setup… System SIOSelect analog output number Analog Output SetupChoose signal Choose the analyzer moduleHold output during calibration Signal value for 0% outputHold output during calibration Output number Operation modeOutputs value on analyzer failure Output #1 Yes Analog Output Updates Per SecondType of installed serial inter- face Baud rate 19200Communication protocol Relay Outputs SetupInvert signal Choose source moduleFunction control Choose signal…System DIO Input numberSystem Configuration and DIAG- Nostics Analyzer Module Diagnostics Diagnostic MenusLoad/Save Module Configura- tion Date and Time Security CodesEntering a level locked by security code System ResetSystem reset Measure Back… Model NGA 2000 TO2 Sensor Caustic Liquid Section Maintenance and ServiceOverview Electrical Shock Hazard Sensor Assembly Refilling SensorSensor Lleak Check Electrolyte ReplacementSensor Replacement Do not tilt Sensor excessively as elec- trolyte may leak Analyzer and I/O expert controls & setup…Linearization Time & Date0000 ppm Linearization temperature values…Linearization… Linearization raw values sensor current…Fuses Flow Sensor ReplacementElectronic Components Printed Circuit BoardsFailure to purge down to ppm levels Section TroubleshootingTroubleshooting Erratic and very insensitive readingsModel NGA 2000 TO2 TO2 NGA 2000 TO2 Trace Oxygen Analyzer Module Section Replacement PartsMatrix Replacement Parts Return of Material Customer ServiceSection Return of Material TrainingModel NGA 2000 TO2 Section Index Model NGA 2000 TO2 Product ELECTROLYTE1 Other precautions Emergency & first aid proceduresPrecautions to be taken in handling Threshold limit value Routes of entryRosemount Warranty Asia Pacific EUROPE, Middle EAST, Africa Latin America