Emerson 3081FG instruction manual Section Troubleshooting, Probe Life, Impedance, Ω

Page 59

Model 3081FG

Instruction Manual

IB-106-3081 Rev. 1.5 September 2002

SECTION 6

TROUBLESHOOTING

Install all protective equipment covers and safety ground leads after trouble- shooting. Failure to install covers and ground leads could result in serious injury or death.

6-1 GENERAL

This troubleshooting section describes how to identify and isolate faults that may develop in the Two-Wire In Situ Oxygen Analyzer.

6-2 PROBE LIFE

The zirconium oxide technology for measuring oxygen is very stable and should provide accu- rate service for several years.

Life of the probe is negatively impacted by:

•Continued operation at elevated tempera- tures above 1300°C (2372°F).

•Operation in processes that contain high levels of sulfur, SO2, or other acidic com- pounds.

Operating conditions with simultaneously high levels of SO2 and low levels of O2 are particu- larly damaging.

The health and accuracy of a given cell is closely related to the resistance, or impedance, of the cell. Figure 6-1 illustrates that the amount of output from a cell for a given O2 value (repre- sented as slope) will remain very stable to the point where cell impedance increases to ap- proximately 100 ohms.

SLOPE (mV/Dec)

50

6

NORMAL	DETERIORATED PERFORMANCE,	DETERIORATED PERFORMANCE,
OPERATIONAL	SLOW RESPONSE,	SLOW RESPONSE,
CONDITIONS	HIGH MEASUREMENT ERROR	HIGH MEASUREMENT ERROR.
		CONDUCT FREQUENT CALIBRA-
		TION CHECKS.
48.0<S<51mV/Dec	45.0<S<48mV/Dec	S<45mV/Dec

IMPEDANCE, Ω

26020059

Figure 6-1. Slope vs. Impedance

Rosemount Analytical Inc. A Division of Emerson Process Management

Troubleshooting 6-1

Image 59

Contents Model 3081FG Essential Instructions Highlights of Changes Page Model 3081FG Table of ContentsProper Calibration Check Gas Flow Rate List of IllustrationsModel 3081 Transmitter Terminal Block List of TablesModel 3081FG Definitions PrefaceModel 3081FG Component Checklist of Typical System Package Contents Section Description and SpecificationsCode Mounting Adapter Stack Side Product MatrixSystem Description System ConfigurationSystem Overview ScopeSystem Features Handling the Analyzer System Considerations Transmitter Typical System InstallationProbe SpecificationsOperating Load Region Lift OFF Maximum Power Supply VoltageOhms VDCInspect Section InstallationPRE-INSTALLATION Mechanical InstallationSide View Bottom View Front ViewMetal Wall Masonry Wall Stack or Duct Horizontal Probe Installation Adjusting Probe Insertion Depth Model 3081FG Installing Model 3081 Transmitter Mounting Holes Cover LockCircuit Terminal END Block TBElectrical Installation Display Positioning AssemblyThermocouple CELL-WH CELL+BK Model 3081 Transmitter 4-20 mA and Signal ConnectionsTerminal Block Conduit Calibration Check Gas Pneumatic InstallationReference Air Package Instrument Air Reference AirFlow SET MAX Point Knob Mounting Holes Outlet ConnectionOutlet Inlet ConnectionGeneral Power UPSection Startup and Operation Proper Calibration Check Gas Flow Rate Reestablishing Proper Calibration Check GAS Flow RateMenu Tree OperationOverview DisplayProgram DiagnosticsCalcheck MenuNavigation Infrared Remote Control IRCO2 Concentration O2 Concentration Analyzer Access Code Or SecurityAnalyzer Access Code Program MenuCell T HI O2 Concentration Indicator Fault ValueO2 Concentration Upper Cell Temperature Fault Value Upper Range VALSET O2 Filter Time Reset MAX Cell TTo Reset Maximum Cell Temperature O2 Concentration Analyzer Access CodeConcentration SET HI Bottle O2SET LO Bottle O2 Model 3081 Transmitter Parameters SET Code Parameter Range DefaultModel 3081 Transmitter Parameters C mV Diagnostics MenuShow Fault 24. Previous Slope Previous Constant 23. Cell ImpedanceCalcheck Menu SW Build NumberSW Build Date Accept LOW O2 27. in MANUAL?29. Accept LOW O2 Slope Model 3081FG Connections Hart Communicator Signal LineSection HART/AMS OverviewMethod 2, For Load Resistance 250 Ohms Analog Output Device Loop ConnectorsMenu Tree for Hart Communicator TWO-WIRE in Situ Oxygen AnalyzerHart Communicator PC OFF-LINE and ON-LINE OperationsDevice Setup From Sheet Basic Setup Detailed From Sheet Signal Condition Detailed Setup Output Hart Communicator Start CAL- Check Method Model 3081FG PC Board Stack Replacement Section Maintenance and ServiceModel 3081 Electronics Replacement Display Board ReplacementTwo-Wire In Situ Oxygen Analyzer Exploded View Oxygen Probe Replacement Oxygen Probe Terminal Block IMPEDANCE, Ω Section TroubleshootingProbe Life Speed Fault IndicationsOfresponse Thermocouple Identifying and Correcting Fault IndicationsFault 1, Open Thermocouple Fault 3, Shorted Thermocouple Fault 5, O2 Cell Open Fault 6, Cell Impedance Too High Fault 5, O2 Cell Open11. Fault 7, Reversed O2 Cell Fault 7, Reversed O2 CellModel 3081FG Section Return of Material Model 3081FG Index No Part Number Description Replacement PartsReplacement Parts List SectionModel 3081FG Section Index Model 3081FG Model 3081FG Page Section Drawings and Schematics Model 3081FG Warranty Two-Wire In Situ Oxygen Analyzer Serial no Order no