Agilent Technologies AGILENT MODELS 6023A and 6028A service manual Basic Test Setup

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Figure 2-3. Basic Test Setup

d.Reduce the resistance of the load to draw an output current of: 29Adc (6023A)

10Adc (6028A)

Check that the unit's CV LED remains lighted.

e.Record the output voltage at the digital voltmeter.

f.Open-circuit the load.

g.When the reading settles, record the output voltage again. Check that the two recorded readings differ no more than:

±0.0027Vdc (6023A)

±0.0090Vdc (6028A)

Source Effect (Line Regulation). Source effect is the change in dc output voltage resulting from a change in ac input voltage from the minimum to the maximum value as specified in Input Power Requirements in the Specifications Table, in the Operating Manual. Proceed as follows:

a.Connect the test equipment as shown in Figure 2-3. Operate the load in constant resistance mode (Amps/Volt) and set resistance to maximum.

b.Connect the unit to the ac power line through a variable autotransformer which is set for low line voltage (104Vac for 120Vac).

c.Turn the unit's power on, and turn up current setting to full output.

d.Turn up output voltage to: 20.0Vdc (6023A)

60Vdc (6028A)

as read on the digital voltmeter.

e.Reduce the resistance of the load to draw an output current of: 10Adc (0.010Vdc across Rm) (6023A)

3.3Adc(0.33Vdc across Rm) (6028A)

Check that the unit's CV LED remains lighted.

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Contents Autoranging Certification Safety Summary Safety Symbol Definitions Printing HistoryTable of Contents Replaceable Parts Troubleshooting Circuit DiagramsSafety Considerations ScopeManual Revisions Item DescriptionCalibration Procedure IntroductionTest Equipment Required Operation Verification TestsType Required Characteristics USE Recommended Model Test Equipment RequiredInitial Setup 1KVACalibration Procedure MONVout IoutMeasurement Techniques Performance TestsCR7 Current-Monitoring Resistor Setup Constant Voltage CV TestsBasic Test Setup RMS Measurement Test Setup, CV Pard Test Peak-To-Peak Measurement Test Setup, CV Pard Test 6023A 6028A KHz Noise, CV Peak-to-Peak PardLoad Transient Recovery Waveform Constant Current CC Tests CC Pard Test Setup Troubleshooting Initial Troubleshooting ProceduresControl Board Test Connector, A2J7 PIN no Signal NameVdc WAVEFORM/CONDITIONS SourceRepair and Replacement Electrostatic ProtectionA2 Control Board Removal A4 Power Mesh Board Removal Overall Troubleshooting ProcedureA3 Front-Panel Board Removal A1 Main Board RemovalUsing the Tables SetupNode MeasurementMain Troubleshooting Setup Main Troubleshooting SetupModified Mains Cord Set For Troubleshooting Troubleshooting No-Output Failures Front-Panel TroubleshootingA2J7-26 A2J7-25 PWM-ON PWM-OFF Defective Check Functional CircuitsBoard Troubleshooting Bias Supplies Symptoms Defective Circuit Check ComponentsSymptoms Defective Check Functional Circuits Board Node + Measurement SourceMeasurement Source Node +Node + N0DE Power Section Blocks Troubleshooting AC-Turn-on CircuitsSetup Measurement Source Setup MeasurementRelay Enable Troubleshooting PWM & ClockPower Limit Troubleshooting DC-To-DC Converter + OUTPWM-ON PWM-OFFTroubleshooting CV Circuit Troubleshooting CC CircuitTroubleshooting OVP Circuit Troubleshooting Down ProgrammerA4U4OUT Waveforms SET Voltage Vdc Node + Page Autoranging Power Block Diagram OverviewBlock Diagram Simplified Schematic Simplified Schematic DC-to-DC Converter Down ProgrammerPfet Control Signals Timing Diagram Constant-Voltage CV CircuitPower-Limit Comparator Constant-Current CC CircuitOvervoltage Protection OVP Circuit Control-Voltage ComparatorInitial-Ramp Circuit Pulse-Width Modulator PWMBias Voltage Detector AC-Surge Dropout DetectorSecond-Delay Circuit Display CircuitsPage Replaceable Parts Reference DesignatorsOrdering Information Description AbbreviationsElectrical Parts CR1CR2 CR3XA2P2 XA2P1Mechanical Parts Control Board Assembly CR3 Page Page Page VR4 VR3VR5 DS1 CR5DS5 VR1 IC A/D Cmos 3-1/2 DGTVR2 NPN SI PfetTS1 Chassis ElectricalA1TB1 A2 Board Mechanical PartsA3 Board Mechanical Parts A4 Board Mechanical PartsOption 220 220V Operation Option 240 240V OperationComponent Location and Circuit Diagrams Schematic Diagram Notes Pin locations for other semi-conductors are shown below Top View, Top Covers Removed Main Board A1 Component Location Control Board A2 Component Location Front-Panel Board A3 Component Location Power Mesh Board A4 Component Location Page Page General Information SpecificationsOption 002 Hardware Table A-1. Specifications, Option Remote Programming Input Compliance Voltage ± Current Programming EnableOutput Impedance 10.2 k ohm ± 5% Temperature Coefficient Status IndicatorsRemote Trip and Remote Reset Timing Power-on PresetMaximum Output Voltage logic high + On State logic lowTable A-1. Specifications, Option Pulse Timing Bias Supplies DC Output Ratings 25C ±Short Circuit Output Current Pard TypicalInstallation Connector Assembly ProcedureFigure A-1. Mating Connector Assembly OperationLocal/Remote Programming Resistance Voltage or Current Remote Resistance Programming Figure A-4. Calculating Value of Series Dropping ResistorFigure A-5. Remote Resistance Programming Remote Monitoring Status Indicators Remote ControlRemote Reset OvervoltagePower-On Preset Figure A-8. Remote ControlAC Dropout Buffer Circuit Multiple Supply System ShutdownMaintenance Bias SuppliesTroubleshooting Resistance and Voltage Programming Troubleshooting Current ProgrammingFigure A-11. Troubleshooting Current Programming of CV Mode Figure A-13. Troubleshooting Status Indicators Page Table A-3. Replacement Parts REF. Desig Model no Description100 VR9 101Indicator and Qualifier Symbols OLD Symbol NEW SymbolLogic Symbols and Definitions 102 DefinitionsSchematic Notes Schematic Diagram Notes 103Schematic Notes Figure A-15. Option 002 Board, Component Location 104Figure A-16. Option 002 Board, Schematic Diagram 105 Page Model 6028A Model 6023A107 From 108