Agilent Technologies AGILENT MODELS 6023A and 6028A manual

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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Agilent Technologies AGILENT MODELS 6023A and 6028A Power Section Blocks, Troubleshooting AC-Turn-on Circuits

Contents

Autoranging Certification Safety Summary Printing History Safety Symbol Definitions Table of Contents Replaceable Parts Scope TroubleshootingCircuit Diagrams Safety Considerations Item Description Manual Revisions Operation Verification Tests Calibration ProcedureIntroduction Test Equipment Required Test Equipment Required Type Required Characteristics USE Recommended Model 1KVA Initial Setup MON Calibration Procedure Iout Vout CR7 Performance TestsMeasurement Techniques Constant Voltage CV Tests Current-Monitoring Resistor Setup Basic 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 6028A Load Transient Recovery Waveform Constant Current CC Tests CC Pard Test Setup Initial Troubleshooting Procedures Troubleshooting WAVEFORM/CONDITIONS Source Control Board Test Connector, A2J7PIN no Signal Name Vdc Electrostatic Protection Repair and Replacement A2 Control Board Removal A1 Main Board Removal A4 Power Mesh Board RemovalOverall Troubleshooting Procedure A3 Front-Panel Board Removal Measurement Using the TablesSetup Node Main Troubleshooting Setup Main Troubleshooting Setup Modified Mains Cord Set For Troubleshooting Front-Panel Troubleshooting Troubleshooting No-Output Failures Board 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 Board Node + N0DE Node +Measurement Source Setup Measurement Power Section BlocksTroubleshooting AC-Turn-on Circuits Setup Measurement Source Power Limit Troubleshooting PWM & ClockRelay Enable PWM-OFF Troubleshooting DC-To-DC Converter+ OUT PWM-ON Troubleshooting CC Circuit Troubleshooting CV Circuit A4U4OUT Troubleshooting Down ProgrammerTroubleshooting OVP Circuit Waveforms SET Voltage Vdc Node + Page Block Diagram Overview Autoranging Power Block Diagram Simplified Schematic Simplified Schematic Down Programmer DC-to-DC Converter Constant-Voltage CV Circuit Pfet Control Signals Timing Diagram Control-Voltage Comparator Power-Limit ComparatorConstant-Current CC Circuit Overvoltage Protection OVP Circuit AC-Surge Dropout Detector Initial-Ramp CircuitPulse-Width Modulator PWM Bias Voltage Detector Display Circuits Second-Delay CircuitPage Reference Designators Replaceable Parts Description Abbreviations Ordering Information CR3 Electrical PartsCR1 CR2 Mechanical Parts XA2P1XA2P2 Control Board Assembly CR3 Page Page Page VR5 VR3VR4 DS5 CR5DS1 VR2 IC A/D Cmos 3-1/2 DGTVR1 Pfet NPN SI Chassis Electrical TS1 A4 Board Mechanical Parts A1TB1A2 Board Mechanical Parts A3 Board Mechanical Parts Option 240 240V Operation Option 220 220V Operation Component 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 Coefficient On 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 Current Connector Assembly Procedure Installation Operation Figure A-1. Mating Connector Assembly Local/Remote Programming Resistance Voltage or Current Figure A-4. Calculating Value of Series Dropping Resistor Remote Resistance Programming Figure A-5. Remote Resistance Programming Remote Monitoring Remote Control Status Indicators Overvoltage Remote Reset Figure A-8. Remote Control Power-On Preset Multiple Supply System Shutdown AC Dropout Buffer Circuit Bias Supplies Maintenance Troubleshooting Current Programming Troubleshooting Resistance and Voltage Programming Figure A-11. Troubleshooting Current Programming of CV Mode Figure A-13. Troubleshooting Status Indicators Page REF. Desig Model no Description Table A-3. Replacement Parts 100 101 VR9 Definitions Indicator and Qualifier SymbolsOLD Symbol NEW Symbol Logic Symbols and Definitions 102 Schematic Diagram Notes 103 Schematic Notes Figure A-15. Option 002 Board, Component Location 104 Schematic Notes Figure A-16. Option 002 Board, Schematic Diagram 105 Page 107 Model 6023AModel 6028A 108 From