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Fluke 8842a instruction manual Main PCA, Ohms Current Source

Models: 8842a

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Figure 9-3. Main PCA, Ohms Current Source

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Fluke 8842a instruction manual Main PCA, Ohms Current Source

Contents

8842A Page Table of Contents 8842A Remote ProgrammingMeasurement Tutorial Maintenance List of Replaceable Parts Schematic Diagrams List of Tables 805-7 List of Figures 805-8 IEEE-488 Interface PCA, Option True RMS AC PCA, Option Xii Introduction and Specifications Options and Accessories Introduction8842A Digital Multimeter Specifications Filter Peak NM SignalRate True RMS AC Voltage Option 8842A-09Crest Factor FrequencyFundamental Frequency For InputsCurrent Full Scale 5½ Digits½ Digits Range Full Scale Resolution Current ½ Digits Through UnknownHours 23±1C Autoranging Rate Power Line FREQUECNCY1Automatic Settling Time Delay FunctionExternal Trigger Timing Characteristics Conversion Time ms 50 Hz 60 Hz 400 HzPower GeneralOperating Instructions Installation Installing the Power-Line FuseConnecting to Line Power Adjusting the Handle Rack Mounting KitsOperating Features Power-Up FeaturesFront and Rear Panel Features Operating Features Local button causes the 8842A to display its Rear Panel Features Display Features Error MessagesError Code Meaning Error CodeRanging Diagnostic Self-TestsOverrange Indication AutorangeManual Range Continuous Trigger ModeExternal Trigger Mode TriggeringAutomatic Settling Time Delay External Trigger Input Option -05 OnlySample Complete Output Option -05 Only Measuring Voltage and Resistance Making MeasurementsInput Overload Protection Limits Measuring CurrentOffset Measurements External Cleaning Measuring Voltage and Resistance8842A Remote Programming Measurement Data Overrange Indication Error Messages BUS SET-UP Procedure CapabilitiesAN Overview of Remote Operation IEEE-488 Address SelectionAN Overview of Remote Operation DEVICE-DEPENDENT Command SET ExampleExplanationDEVICE-DEPENDENT Command SET Device-Dependent Command Set Bn Offset Commands Cn Calibration CommandsDn Display Commands Fn Function Commands Get CommandsCommand Output String Meaning12. G0 Get Instrument Configuration 13. G1 Get SRQ Mask14. G2 Get Calibration Prompt 15. G3 Get User-Defined Message 16. G4 Get Calibration Status19. G7 Get Error Status 17. G5 Get IAB Status18. G6 Get YW Status 23. P0 Put Instrument Configuration Numeric Entry CommandPut Commands 20. G8 Get Instrument Identification24. P1 Put SRQ Mask 25. P2 Put Calibration ValueRn Range Commands Sn Reading Rate Commands26. P3 Put User-Defined Message Tn Trigger Mode Commands Trigger Selection Logic DiagramYn Suffix Commands Wn Terminator Commands31. X0 Clear Error Register Command 33. Z0 Self-Test CommandDevice-Clear Command 35. ? Single-Trigger CommandInput Syntax Definitions Input ProcessingERROR-PRODUCING Characters DEVICE-DEPENDENT MessagesInterface Messages Syntax Rules Incorrect exampleOutput Data Loading Output DataTypes of Output Data Numeric Data and Error MessagesOverrange Indication Error Messages Measurement DataStatus Data Error MessagesOverrange Indication Output PriorityService Requests Serial Poll RegisterSRQ Mask SetUniversal Commands Interface MessagesAddress Messages TALK-ONLY Mode Addressed CommandsImmediate Mode Commands Remote CalibrationTiming Considerations Immediate-Mode Commands for Various Controllers Example ProgramsExample Programs 10. Example Program Taking Readings with Local Control 11. Example Program Using the Serial Poll Register 12. Example Program Record Errors During Selftest 13. Example Programs Using the IBM PC 14. Example Programs Using the IBM PC F3-1402.wmf F3-1403.wmf F3-1404.wmf F3-1405.wmf F3-1406.wmf F3-1407.wmf F3-1408.wmf F3-1409.wmf F3-1410.wmf F3-1411.wmf ASCII/IEEE Std 488-1978 Bus Codes 8842A Measurement Tutorial Circuit Loading Error DC Voltage MeasurementInput Bias Current Error Measuring Input Bias Current ErrorWire Ohms Resistance MeasurementCorrecting for Test Lead Resistance in 2-Wire Ohms Test Current Full Scale VoltageTesting Diodes Testing Electrolytic CapacitorsApplications of the Ohms Functions DC Current Measurement Precision Current SourceBurden Voltage Error Calculation Reducing Thermal VoltagesAC Voltage and Current Measurement True RMS MeasurementWaveform Comparison AC Voltage and Current Measurement Crest Factor AC-Coupled AC MeasurementsZero-Input VAC Error Combined AC and DC MeasurementsBandwidth Reduction of Zero-Input Error 20Ω RangesMaking Accurate HIGH-RESISTANCE Measurements 10. Shielding for Low Voltage Measurements12. Leakage Resistance in High Resistance Measurement Theory of Operation True RMS AC Option VAC Scaling MA AC Scaling Overall Functional Description Detailed Circuit Description DC ScalingDC Scaling VDC Scaling DC Scaling VDC and mA DCVDC Protection MA DC ScalingAnalog Filter TRACK/HOLD Circuit Track/Hold AmplifierTRACK/HOLD Circuit Track Configuration Timing Diagram for One A/D CyclePre-Charge Configuration Settling ConfigurationHold Configuration Precision Voltage ReferenceOhms Current Source Ohms Current SourceOhms Protection Ohms FunctionsOhms Scaling 20. A/D Converter Analog-to-Digital Converter Timing/Data Control Precision DACBootstrap Supplies Display23. A/D Amplifier Keyboard Digital Controller13. Digital Controller Block Diagram In-Guard Microcomputer 14. Read/Write Timing Diagrams for Internal Bus 30. A/D Control and Computation Slow Medium Fast Power Line FrequencyFunction and Range Control Calibration CorrectionKeyboard/Display Control Troubleshooting ModesGuard Crossing Guard-Crossing CommunicationPower Supply Guard Crossing IEEE-488 Interface OptionOut-Guard Microcomputer Bus Interface CircuitrySignal Conditioning IEEE-488 Interface Power SupplyVAC Scaling MA AC Scaling Frequency Response TrimmingTrue RMS AC-to-DC Conversion Static awareness Dow Chemical Maintenance External Trigger Polarity Selection Option -05 Only Minimum Specifications Recommended Model Instrument TypePerformance Test Frequency Range Minimum Required Accuracy All RangesDC Voltage Test Step Range Input Slow Medium Fast MIN MAXAC Voltage Test Option -09 Only Voltage FrequencyResistance Test New Offset must be stored for each new range selectedSlow Medium MIN MAX DC Current TestDisplayed Reading Fast MIN MAXStep Number Range CalibrationAC Current Test Option -09 Only Input Current FrequencyBasic Calibration Procedure Initial Procedure12. A/D Calibration Calibration FunctionsL O W a B L E Error Step Displayed PromptStep Input Offset and Gain Calibration StepDisplayed Prompt VDC VAC1 HIGH-FREQUENCY AC Calibration Advanced Features and Special Considerations Storing Variable InputsStep Displayed PROMPT1,2 Procedure Function LOW Prompt High Prompt Calibrating Individual RangesVerifying Calibration Erasing Calibration Memory Tolerance CheckCalibration AC Calibration AT Other FrequenciesOptimizing USE of the 5450A ToleranceRemote Calibration Optimizing Use of the 5450AFront Panel Feature Corresponding CommandComments 8842A Timing Considerations Remote Erasure Example Calibration ProgramDisassembly Procedure Example A/D Calibration ProgramA Disassembly Case RemovalF6-062.wmf F6-063.wmf F6-064.wmf True RMS AC PCA Removal Option -09 Only IEEE-488 Interface PCA Removal Option -05 OnlyMain PCA Removal Maintenance Reassembly Procedure Front Panel DisassemblyReassembly Procedure Front Panel Disassembly Removing the Display Window Internal Fuse Replacement TroubleshootingInitial Troubleshooting Procedure Troubleshooting 16. Overall State Table T6-162.wmf 17. Circuitry Tested by the Analog Self-Tests Diagnostic Self-Tests Self-Test Descriptions Test NumberTest Point Voltage Maintenance 8842A Digital Controller Troubleshooting IN-GUARD Microcomputer SystemIn-Guard Microcomputer Address Latch U219 Calibration Memory U220 Display SystemDisplay Control U212 To-8 Strobe Decoder U213 Analog Control Signals Evaluating Static Signals Device REF. DES21. Analog Control Logic States Evaluating Dynamic Signals DC Scaling TroubleshootingPIN or Device Supply VoltageTrack/Hold Troubleshooting Ohms Current Source Troubleshooting13. Typical Output Waveforms for Track/Hold Circuit TP103 Precision Voltage Reference Troubleshooting 66. A/D Converter Troubleshooting 14. Output of A/D Amplifier TP10115. Waveforms at U101-24 and U101-25 Power Supply Troubleshooting For fire protection, use exact fuse replacement only17. Waveforms at TP102 for Several Inputs on 2V DV Range Test Point Minimum MaximumIEEE-488 Interface Troubleshooting Option Service PositionDiagnostic Program Troubleshooting Switches ConfigurationTrue RMS AC Troubleshooting Option Port BITMajor Problems Defective RangesDefective Stage Input Voltage Voltage AT TP801Voltage AT TP802 More Obscure Problems Internal Cleaning Guard Crossing TroubleshootingCleaning Printed Circuit Assemblies Cleaning After Soldering 21. Guard Crossing Test Waveforms8842A List of Replaceable Parts 8842A HOW to Obtain Parts Manual Status InformationService Centers Newer InstrumentsAssembly Fluke Part no REF of Option noRevision Level F7-011.wmf F7-012.wmf F7-013.wmf F7-014.wmf A1 Main PCA CABLE, Display HEADER,1 ROW,.156CTR,6 PIN 8842A F7-03.wmf A2 Display PCA F7-03.wmf Supply Codes for Manufacturers Supply2.wmf Service Centers Service2.wmf 8842A Options and Accessories 8842A Model DescriptionNumber Option Accessories Current Shunt 80J-10 Current Probes Y8100, Y8101, 80i-400High Voltage Probes 80K-6 and 80K-40 8842A Option -05 IEEE-488 Interface 805-2 External Controls Maintenance Programming InstructionsList of Replaceable Parts List of Replaceable Parts 805-6 805-7 805-8 Option -09 True RMS AC 809-2 Option -09 True RMS AC Operating Instructions 809-5 Option -09 True RMS AC PCA 809-7 809-8 Schematic Diagrams 8842A Schematic Diagrams F9-012.wmf Main PCA, A/D Converter F9-022.wmf Main PCA, Ohms Current Source F9-032.wmf Main PCA, Digital F9-042.wmf Main PCA, Power Supply F9-052.wmf Display PCA F9-062.wmf F9-071.wmf F9-072.wmf IEEE-488 Interface PCA, Option IEEE-488 Interface PCA, Option -08