Agilent Technologies AGILENT MODELS 6023A and 6028A Using the Tables, Node, Setup, Measurement

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Table 3-1 gives the signals for each of the test points on the control board test connector. This connector is provided in service kit P/N 06033-60005. The measurements given here include bias and reference voltages as well as power supply status signals and waveform information.

Table 3-2 provides troubleshooting information based on the status of the PWM-ON and PWM-OFF signals which drive the PFETs. This table is used for no-output failures.

Tables 3-3 and 3-4 give measurements for the test points on the A3 front-panel board and possible failure symptoms respectively.

Table 3-5 describes possible symptoms for overall performance failures of the power supply. It is necessary to have a properly working front-panel before using this table.

Chapter 6 contains schematic diagrams and voltage levels, and component location diagrams to help you locate components and test points.

Make most voltage measurements (except DC-to-DC Converter and ac mains-connected circuits) referenced to the unit's output common which is accessible at rear-panel terminal VM. All voltages are ± 5% unless a range is given.

Using the Tables

Typically there will be two types of power supply failures; no-output and performance failures.

1.No-OUTPUT FAILURE: Start with the TROUBLESHOOTING NO-OUTPUT FAILURES section which references Tables 3-1 and 3-3.

2.PERFORMANCE FAILURE: If the power supply produces an output but does not perform to specifications, begin by verifying the measurements at the A2J7 test connector using Table 3-1. Next, verify the front-panel by doing the procedure outlined in the FRONT-PANEL TROUBLESHOOTING section. After the front-panel has been verified consult Table 3-5 for the performance failure symptom which seems closest to the one observed and proceed to the functional circuit given for that failure.

The circuits referenced in Tables 3-2 and 3-5 are derived from functional blocks of circuits in the power supply. These blocks are given in the Power Supply Blocks section starting on page 35. Troubleshooting information for each block will include a brief description of the circuit involved. The columns provided in each block are as follows:

NODE:

This column lists the nodes where the measurements should be taken. In some cases this will be

 

stated as NODE ( + ) and NODE (- ) where the first is the test node and the second is the

 

reference.

SETUP:

If a certain setup is required for the measurement, it will be given in this column.

MEASUREMENT:

This column indicates what the expected measurement is for the given node.

SOURCE:

If applicable, the components which generate the signal will be provided in this column .

Some blocks will have Input and Output sections. The input section will have a source column to indicate which components generated the measured signal. The output section will list all the important output signals from that block. However, because the outputs of one block are the inputs to another, the schematic should be consulted if an output measurement is incorrect. This will indicate the next circuit block to be trouble shot.

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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