Agilent Technologies AGILENT MODELS 6023A and 6028A Power Section Blocks, Setup Measurement

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Input:
NODE ( + )	MEASUREMENT	SOURCE
A2U4 (IN), A2C16 (-)	≈ -24Vdc	A1U1, AlC1 ( + )
Outputs:
NODE ( + )	N0DE ( - )	MEASUREMENT
A2U4 (ADJ)	A2U4 (OUT)	1.25Vdc
A2VR2 (cath.)	A2VR2 (anode)	11.7Vdc
A2R33, A2R34	A2VR2 (cath.)	2.05Vdc

To check if load on -15V is shorted, remove jumper A2W3.

Refer to Down Programmer, page 39, for the + 8.9V bias supply, and refer to OVP Circuit, page 39, for the +2.5V bias supply.

Power Section Blocks

This section contains the blocks referenced in Tables 3-2 and 3-5.

Troubleshooting AC-Turn-on Circuits

Relay A1K1 closes at 1.0 seconds and DROPOUT goes high at 1.1 seconds after 20V (5V UNREG) reaches about 11Vdc. DROPOUT high enables the PWM if OVERVOLTAGE, and OVERTEMPERATURE are also high.

Circuits Included. AC-Surge-&-Dropout Detector, Bias Voltage Detector, U11A, 1-Second Delay and Relay Driver--all on A2 control board.

Setup. The Main Troubleshooting Setup, page 29. Apply the ac mains voltage to the bias transformer, and set the external supply to 0Vdc.

Inputs:
NODE ( + ) *	SETUP	MEASUREMENT	SOURCE
A2J3-1	wait 2s	5.0Vdc	A2Q3 (emit.)
A2J3-22		20Vdc	A1CR6, AlCR7
A2U20-8,10		f.w.rect.,1-2Vpk	A1CR8,AlCR9
A2U22-13		TTL sq wave, 20KHz	A2U22-6
Outputs:
NODE ( + ) *	SETUP	MEASUREMENT
A2U20-5	cycle power	transition 0 to 13.5Vdc
A2U20-2	cycle power	transition 0 to 1.4Vdc
A2Q6-1	cycle power	transition 0 to 5.0 to 0.3Vdc
A2Q6-9	cycle power	transition 0 to 0.3 to 5.0Vdc
A2U20-6	wait 2s	< 0.25Vdc
A2U20-1,14	wait 2s	hi (5Vdc)
A2U11-3	cycle power	transition lo to hi to lo
A2U18-10	cycle power	burst 1.25 KHz sq. wave 1.1s

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Contents Autoranging Certification Safety Summary Printing History Safety Symbol DefinitionsTable of Contents Replaceable Parts Scope TroubleshootingCircuit Diagrams Safety ConsiderationsItem Description Manual RevisionsOperation Verification Tests Calibration ProcedureIntroduction Test Equipment RequiredTest Equipment Required Type Required Characteristics USE Recommended Model1KVA Initial SetupMON Calibration ProcedureIout VoutCR7 Performance TestsMeasurement Techniques Constant Voltage CV Tests Current-Monitoring Resistor SetupBasic Test Setup RMS Measurement Test Setup, CV Pard Test Peak-To-Peak Measurement Test Setup, CV Pard Test KHz Noise, CV Peak-to-Peak Pard 6023A 6028ALoad Transient Recovery Waveform Constant Current CC Tests CC Pard Test Setup Initial Troubleshooting Procedures TroubleshootingWAVEFORM/CONDITIONS Source Control Board Test Connector, A2J7PIN no Signal Name VdcElectrostatic Protection Repair and ReplacementA2 Control Board Removal A1 Main Board Removal A4 Power Mesh Board RemovalOverall Troubleshooting Procedure A3 Front-Panel Board RemovalMeasurement Using the TablesSetup NodeMain Troubleshooting Setup Main Troubleshooting SetupModified Mains Cord Set For Troubleshooting Front-Panel Troubleshooting Troubleshooting No-Output FailuresBoard PWM-ON PWM-OFF Defective Check Functional CircuitsA2J7-26 A2J7-25 Node + Measurement Source Troubleshooting Bias SuppliesSymptoms Defective Circuit Check Components Symptoms Defective Check Functional Circuits BoardNode + N0DE Node +Measurement Source Setup Measurement Power Section BlocksTroubleshooting AC-Turn-on Circuits Setup Measurement SourcePower Limit Troubleshooting PWM & ClockRelay Enable PWM-OFF Troubleshooting DC-To-DC Converter+ OUT PWM-ONTroubleshooting CC Circuit Troubleshooting CV CircuitA4U4OUT Troubleshooting Down ProgrammerTroubleshooting OVP Circuit Waveforms SET Voltage Vdc Node + Page Block Diagram Overview Autoranging PowerBlock Diagram Simplified Schematic Simplified Schematic Down Programmer DC-to-DC ConverterConstant-Voltage CV Circuit Pfet Control Signals Timing DiagramControl-Voltage Comparator Power-Limit ComparatorConstant-Current CC Circuit Overvoltage Protection OVP CircuitAC-Surge Dropout Detector Initial-Ramp CircuitPulse-Width Modulator PWM Bias Voltage DetectorDisplay Circuits Second-Delay CircuitPage Reference Designators Replaceable PartsDescription Abbreviations Ordering InformationCR3 Electrical PartsCR1 CR2Mechanical Parts XA2P1XA2P2 Control Board Assembly CR3 Page Page Page VR5 VR3VR4 DS5 CR5DS1 VR2 IC A/D Cmos 3-1/2 DGTVR1 Pfet NPN SIChassis Electrical TS1A4 Board Mechanical Parts A1TB1A2 Board Mechanical Parts A3 Board Mechanical PartsOption 240 240V Operation Option 220 220V 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 Status Indicators Table A-1. Specifications, Option Remote ProgrammingInput Compliance Voltage ± Current Programming Enable Output Impedance 10.2 k ohm ± 5% Temperature CoefficientOn State logic low Remote Trip and Remote Reset TimingPower-on Preset Maximum Output Voltage logic high +Pard Typical Table A-1. Specifications, Option Pulse TimingBias Supplies DC Output Ratings 25C ± Short Circuit Output CurrentConnector Assembly Procedure InstallationOperation Figure A-1. Mating Connector AssemblyLocal/Remote Programming Resistance Voltage or Current Figure A-4. Calculating Value of Series Dropping Resistor Remote Resistance ProgrammingFigure A-5. Remote Resistance Programming Remote Monitoring Remote Control Status IndicatorsOvervoltage Remote ResetFigure A-8. Remote Control Power-On PresetMultiple Supply System Shutdown AC Dropout Buffer CircuitBias Supplies MaintenanceTroubleshooting Current Programming Troubleshooting Resistance and Voltage ProgrammingFigure A-11. Troubleshooting Current Programming of CV Mode Figure A-13. Troubleshooting Status Indicators Page REF. Desig Model no Description Table A-3. Replacement Parts100 101 VR9Definitions Indicator and Qualifier SymbolsOLD Symbol NEW Symbol Logic Symbols and Definitions 102Schematic Diagram Notes 103 Schematic NotesFigure A-15. Option 002 Board, Component Location 104 Schematic NotesFigure A-16. Option 002 Board, Schematic Diagram 105 Page 107 Model 6023AModel 6028A 108 From