Agilent Technologies AGILENT MODELS 6023A and 6028A Load Transient Recovery Waveform

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6023A

6028A

Figure 2-7. Load Transient Recovery Waveform

Temperature Coefficient. (6023A) Temperature coefficient (TC) is the change in output voltage for each °C change in ambient temperature with constant ac line voltage, constant output voltage setting and constant load resistance. Measure temperature coefficient by placing the unit in an oven, varying the temperature over a range within the unit's operating temperature range, and measuring the change in output voltage. Use a large, forced air oven for even temperature distribution. Leave the unit at each temperature measurement for half hour to ensure stability in the measured variable. Measure the output voltage with a stable DVM located outside the oven so voltmeter drift does not affect the measurement accuracy. To measure offset TC, repeat the procedure with output voltage set to 0.10Vdc.

Proceed as follows:

a.Connect DVM between +S and -S.

b.Place power supply in oven, and set temperature to 30°C.

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

d.Turn up output voltage to 20Vdc as read on the DVM.

e.After 30 minutes stabilization record the temperature to the nearest 0.1°C. Record the output voltage at the DVM.

f.Set oven temperature to 50°C.

g.After 30 minutes stabilization, record the temperature to the nearest 0.1°C. Record output voltage.

h.Check that the magnitude of the output voltage change is no greater than 32mV.

Drift (Stability) (6023A). Drift is the change in output voltage beginning after a 30-minute warm-up during 8 hours operation with constant ac input line voltage, constant load resistance and constant ambient temperature. Use a DVM and record the output at intervals, or use a strip-chart recorder to provide a continuous record. Check that the DVM's or recorder's specified drift during the 8 hours will be no more than 0.001%. Place the unit in a location with constant air temperature preferably a large forced-air oven set to 30°C and verify that the ambient temperature does not change by monitoring with a thermometer near the unit. Typically the drift during 30 minute warm-up exceeds the drift during the 8-hour test. To measure offset drift, repeat the procedure with output voltage set to 0.10Vdc.

a.Connect DVM between + S and - S.

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

c.Turn up output voltage to 20Vdc as read on the digital voltmeter.

d.After a 30 minute warmup, note reading on DVM.

e.The output voltage should not deviate more than 5mV from the reading obtained in step d over a period of 8 hours.

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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 IoutCR7 Performance TestsMeasurement Techniques 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 TroubleshootingBoard PWM-ON PWM-OFF Defective Check Functional CircuitsA2J7-26 A2J7-25 Troubleshooting Bias Supplies Symptoms Defective Circuit Check ComponentsSymptoms Defective Check Functional Circuits Board Node + Measurement SourceNode + N0DE Node +Measurement Source Power Section Blocks Troubleshooting AC-Turn-on CircuitsSetup Measurement Source Setup MeasurementPower Limit Troubleshooting PWM & ClockRelay Enable Troubleshooting DC-To-DC Converter + OUTPWM-ON PWM-OFFTroubleshooting CV Circuit Troubleshooting CC CircuitA4U4OUT Troubleshooting Down ProgrammerTroubleshooting OVP Circuit 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 CR3Mechanical Parts XA2P1XA2P2 Control Board Assembly CR3 Page Page Page VR5 VR3VR4 DS5 CR5DS1 VR2 IC A/D Cmos 3-1/2 DGTVR1 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 Option 002 Hardware SpecificationsGeneral Information 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 107 Model 6023AModel 6028A From 108
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