Agilent Technologies 6023A Manuel de service

SERVICE MANUALAUTORANGINGDC POWER SUPPLYAGILENT MODELS 6023A and 6028AFOR INSTRUMENTS WITH SERIAL NUMBERSAgilent Model 6023A; Serials US36490101 an

10Table 2-1. Test Equipment RequiredTYPE REQUIRED CHARACTERISTICS USE RECOMMENDED MODELOscilloscope Sensitivity: 1 mVBandwidth: 20MHz & 100MHzInp

100Table A-3. Replacement PartsREF. DESIG. MODEL NO. PART NO. DESCRIPTIONR22 All 0686-1525 fxd. film 1.5K 5% 1/4WR23 All 0683-1535 fxd. film 15K 5% 1

101Table A-3. Replacement PartsREF. DESIG. MODEL NO. PART NO. DESCRIPTIONU19 6023A 1826-0393 IC Voltage Reg.U19 6028A 5060-2942 IC Voltage Reg. heats

102DefinitionsHigh = more positiveLow = less positiveIndicator and Qualifier SymbolsOR functionPolarity indicator, shown outside logic symbol. Any mar

103SCHEMATIC NOTES1. ALL RESISTORS ARE IN OHMS, ± 5%, 1/4W, UNLESS OTHERWISE INDICATED.2. ALL CAPACITORS ARE IN MICROFARADS, UNLESS OTHERWISE INDICA

104Schematic Notes1. W1 in normally open position.2. W3 & W4 jumpered3. Relays K1, K2 normally closed4. S1A and S1B are located at the rear pa

105Figure A-16. Option 002 Board, Schematic Diagram

107BBackdatingManual backdating describes changes that must be made to this manual for power supplies whose serial numbers are lowerthan those listed

1086023A In the parts list for the Chassis Mechanical change the following: FROM TOCover-top 06023-00020 06023-00002Cover bottom 06023-00022 06

11Table 2-1. Test Equipment Required (continued)TYPE REQUIRED CHARACTERISTICS USE RECOMMENDED MODELSwitch SPST, 30A @ 20V PDC Power Supply Voltage ra

12Table 2-2. Calibration ProcedureTEST TESTEDVARIABLETEST POINTS TEST SEQUENCE AND ADJUSTMENTS EXPECTEDRESULTSMeter F/SAdjust.Meter Ref.VoltageA2J3 p

13Table 2-2. Calibration Procedure (continued)TEST TESTEDVARIABLETEST POINTS TEST SEQUENCE AND ADJUSTMENTS EXPECTEDRESULTSPowerLimitAdjust.V(OUT)I(OU

14Table 2-3. Guide to Recalibration After RepairPrinted CircuitBoardBlock Name Circuit WithinBlockRef.DesignatorPerform TheseProcedures*A1 Main Board

15The substitution of the load resistor requires adding a load switch to open and short the load in the CC or CV loadregulation tests. The load trans

16 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 u

17f. Record the output voltage at the digital voltmeter.g. Adjust autotransformer to the maximum for your line voltage.h. When the reading settles

18the unit's output voltage. To reduce common-mode noise pickup, set up the oscilloscope for a differential, two-channelvoltage measurement. To r

196023A 6028AFigure 2-6. 20KHz Noise, CV Peak-to-Peak PARDLoad Transient Recovery Time. Specified for CV operation only; load transient recovery tim

2CERTIFICATIONAgilent Technologies, Inc. certifies that this product met its published specifications at time of shipment from the factory.Agilent Tec

20 6023A 6028A Figure 2-7. Load Transient Recovery Waveform Temperature Coefficient. (6023A) Temperature coefficient (TC) is the change in out

21Constant Current (CC) TestsCC Setup. Constant-current tests are analogous to constant-voltage tests, with the unit's output short circuited and

220.25Ω (6023A)2.0Ω (6028A)load resistor that is capable of safely dissipating 250 watts. Proceed as follows:a. Connect the test equipment as shown i

233TroubleshootingMaintenance described herein is performed with power supplied to the instrument, and protective coversremoved. Such maintenance sho

24Table 3-1. Control Board Test Connector, A2J7PIN NO. SIGNAL NAME Vdc WAVEFORM/CONDITIONS SOURCEDigital-Circuits Bias & Reference Voltages1 +5V

25Electrostatic ProtectionThe following caution outlines important precautions which should be observed when working with static sensitivecomponents i

26To avoid the possibility of personal injury, remove the power supply from operation before opening thecabinet. Turn off ac power and disconnect the

27A4 Power Mesh Board RemovalAfter removing the inside cover, remove the A4 power mesh board by lifting, using the large aluminum heatsink as ahandle.

28Table 3-1 gives the signals for each of the test points on the control board test connector. This connector is provided inservice kit P/N 06033-6000

29Main Troubleshooting SetupFigure 3-1 shows the troubleshooting setup for troubleshooting all of the unit except the front-panel and initial no outpu

3SAFETY SUMMARYThe following general safety precautions must be observed during all phases of operation, service and repair of thisinstrument. Failure

30As a convenience in implementing the troubleshooting setup, prepare cord sets as shown in Figure 3-2. This facilitatesconnecting the unit's inp

31d. With the LINE switch off, connect an external dc supply to the outside prongs of the unit’s power receptacle. Ignorepolarity as the unit’s input

32Table 3-2. No-Output Failures(Bias supplies and AC turn-on circuit functioning)Status of PFET on/off-PulsesPWM-ONA2J7-26PWM-OFFA2J7-25DEFECTIVEBOAR

33Troubleshooting Bias Supplies +5V on A2 Control Board. The PWM A2U6 includes a clock generator (45KHz set by A2R53 and A2C26), and a currentlimit (2

34Table 3 5. Performance Failure Symptoms (continued)SYMPTOMS DEFECTIVEBOARDCHECK FUNCTIONAL CIRCUITSCV overshoots A2 A2U10A, A2CR20, A2R94Output noi

35Input:NODE ( + ) MEASUREMENT SOURCEA2U4 (IN), A2C16 (-)≈ -24VdcA1U1, AlC1 ( + )Outputs:NODE ( + ) N0DE ( - ) MEASUREMENTA2U4 (ADJ) A2U4 (OUT) 1.25Vd

36A2U18-13 cycle power five 100ms pulses then hiA2U18-12 cycle power two 200ms pulses then hiA2U18-15 cycle power transition lo to hi at 800 msecA2U17

37+ OUT 40 10 3.8Vdc (OVERRANGE)+ OUT 40 2 2.0Vdc (CV)+ OUT 40 2 short A2J3-4 toA2J3-80.0VdcTroubleshooting DC-To-DC ConverterParallel NOR gates A4U2A

38Troubleshooting CV CircuitV-MON, the output of CV Monitor Amp A2U7, is 1/4 the voltage between + S and - S. CV Error Amp A2U8 comparesV-MON to CV PR

39If the failure symptoms include output current oscillation, check if the differentiator circuit is at fault by removing resistorA2R16 (3.3M ohm ). I

4SAFETY SUMMARY (continued)GENERALAny LEDs used in this product are Class 1 LEDs as per IEC 825-1.ENVIRONMENTAL CONDITIONSThis instrument is intended

40Figure 3-3. Waveforms

41Outputs:NODE ( - ) = A2J7-4SET VOLTAGE (Vdc)NODE ( + ) EXTERNAL INTERNAL SETUP MEASUREMENTA2U9 (OUT) - 2.5VdcA2U14-10 10 1.0VdcA2U14-11 - 1.5VdcA2J3

434Principles of OperationAutoranging PowerAutoranging allows the unit to be compact and light weight and yet to deliver a range of output voltage cur

44Figure 4-2. Block Diagram

45Control signals flow from right to left with separate circuits for constant-voltage, constant-current and power-limit control.These three control ci

46Figure 4-3. Simplified Schematic

47The unit checks that the + 5Vdc bias voltage and the ac mains voltage are within acceptable limits as part of its turn onsequence. When + 5Vdc comes

48Figure 4-4. PFET Control Signals Timing DiagramConstant-Voltage (CV) CircuitThe Constant-Voltage Circuit compares the output voltage to the user-se

49Constant-Current (CC) CircuitThe Constant-Current Circuit compares the output current to the user-set CC PROGRAM Voltage to produce the CCCONTROL Vo

5TABLE OF CONTENTSIntroduction ...

50A2CR24. The A2R113-A2R114 voltage divider sets the maximum CP voltage to + 1.5Vdc and assures that the diode withthe lower control voltage will be f

51by inhibiting the PWM through the DROPOUT signal from the l-Second-Delay Circuit. Mains Detect signal, which isfullwave-rectified ac from the + 5Vdc

535Replaceable PartsIntroductionThis chapter contains information for ordering replacement parts. Table 5-3 lists parts in alpha-numeric order by refe

54Ordering InformationTo order a replacement part, address order or inquiry to your local Agilent Technolgies sales office. Specify the followinginfor

55Table 5-3. A1 Main Board Parts ListRef. Desig. Agilent Model Agilent Part Number DescriptionELECTRICAL PARTSAl 6023A 06038-60021 Main Board Assembl

56Table 5-3. A1 Main Board Parts List (continued)Ref. Desig. Agilent Model Agilent Part Number DescriptionR8 6028A 0699-0118Resistor 20Ω 0.1% 0.1WR9

57Table 5-4. A2 Control Board Parts ListRef. Desig. Agilent Model Agilent Part Number DescriptionELECTRICAL PARTSA2 06038-61023 Control Board Assembl

58Table 5-4. A2 Control Board Parts List (continued)Ref. Desig. Agilent Model Agilent Part Number DescriptionC50 6023A 0160-0167Capacitor, 0.082µF 10

59Table 5-4. A2 Control Board Parts List (continued)Ref. Desig. Agilent Model Agilent Part Number DescriptionR6 All 0683-5125Resistor 5.1KΩ 5% 1/4WR7

6Overvoltage Protection (OVP) Circuit...

60Table 5-4. A2 Control Board Parts List (continued)Ref. Desig. Agilent Model Agilent Part Number DescriptionR48,49 All 0686-1315Resistor 130Ω 5% 1/2

61Table 5-4. A2 Control Board Parts List (continued)Ref. Desig. Agilent Model Agilent Part Number DescriptionR85 All 0698-3450Resistor 42.2KΩ 1% 1/8W

62Table 5-4. A2 Control Board Parts List (continued)Ref. Desig. Agilent Model Agilent Part Number DescriptionR139 All 0757-0442Resistor 10KΩ 1% 1/8WR

63Table 5-5. A3 Front-Panel Board Parts ListRef. Desig. Agilent Model Agilent Part Number DescriptionELECTRICAL PARTSA3 6023A 06023-60020 Front-Panel

64Table 5-5. A3 Front-Panel Board Parts ListRef. Desig. Agilent Model Agilent Part Number DescriptionR68 All 0698-6362Resistor, fixed film 1KΩ 0.1% 1

65Table 5-6. A4 Power Mesh Parts ListRef. Desig. Agilent Model Agilent Part Number DescriptionA4 06038-61022 Power Mesh AssemblyC1 All 0160-5891Fixed

66Table 5-6. A4 Power Mesh Parts List (continued)Ref. Desig. Agilent Model Agilent Part Number DescriptionR24 All 0757-0464 Fixed film 90.9K 1% A 1/8

67Table 5-7. Other Replacement AssembliesRef. Desig. Agilent Model Agilent Part Number DescriptionA1 Board Mechanical Parts6023A 1251-0600 Contact-co

68Table 5-7. Other Replacement Assemblies (continued)Ref. Desig. Agilent Model Agilent Part Number DescriptionAll 4040-1954 Window, display6023A 5020

696Component Location and Circuit DiagramsThis chapter contains component location diagrams, schematics, and other drawings useful for maintenance of

71IntroductionScopeThis manual contains information for troubleshooting the Agilent 6023A or 6028A 200W Autoranging Power Supply to thecomponent level

70Table 6-1. Schematic Diagram Notes1. denotes front-panel marking.2.denotes rear-panel marking.3. Complete reference designator consists of componen

71Table 6-1. Schematic Diagram Notes (continued)Pin locations for other semi-conductors are shown below:

72Figure 6-1. Top View, Top Covers Removed

73Figure 6-2. Main Board (A1) Component Location

74Figure 6-3. Control Board (A2) Component Location

75Figure 6-4. Front-Panel Board (A3) Component Location

76Figure 6-5. Power Mesh Board (A4) Component Location

77Figure 6-6. Power Mesh & Control Board Schematic Diagram

78Figure 6-7. Front Panel Board Schematic Diagram

79ASystem Option 002General InformationThis option facilitates the operation of the power supply in an automated system. Four major circuit blocks pro

8Manual RevisionsAgilent Technologies instruments are identified by a 10-digit serial number. The format is described as follows: first twoletters ind

80Table A-1. Specifications, Option 002Remote ProgrammingResistance Programming: 0 to 4K ohm provides 0 to maximum rated voltage or current output.Ac

81Table A-1. Specifications, Option 002 (continued)Voltage Range: +4.75V to 16VCurrent Drain: 20mA maximumStatus Indicator output:Open collector outp

82Table A-1. Specifications, Option 002 (continued)Pulse TimingLow Bias or AC DROPOUT will go false after 5V supply stabilizes.Bias SuppliesDC Output

83InstallationWhen installing the board, perform the following steps:a. Remove the top and inner cover of the power supply as discussed in Section 3

84Figure A-1. Mating Connector AssemblyOperationThe following paragraphs provide the operating instructions necessary to interface a 002-equipped pow

85Figure A-2. 002 Option Rear Panel Connector J3 and Switches A1 and A2.Local/Remote ProgrammingWhen switching to local/ control, remember to set Fro

86Figure A-3. Accessing Local Programming While In Remote Programming ModeIf solid state circuitry is used, connect the Control Isolator Bias to a dr

87Figure A-4. Calculating Value of Series Dropping ResistorRemote Resistance ProgrammingCheck switches A1 and A2 on the rear panel, they must be in t

88Figure A-5. Remote Resistance ProgrammingFigure A-6. Voltage Programming of Output Voltage and Current

89Current Programming (Figure A-7). Check switches A1 and A2 on the rear panel, they must be in the correct positionsfor CV and CC current programming

92Calibration and VerificationIntroductionThis section provides test and calibration procedures. The operation-verification tests comprise a short pro

90Output impedance is l0K ohm: the monitoring device input impedance should be at least 1M ohm to limit error to 1% +basic accuracy; 10M ohm to limit

91Remote Trip. A negative-going edge applied to terminal J3-30 ( TRIPREMOTE ) will shut down the power supply,reducing the output voltage to near zero

92Figure A-8. Remote ControlPower-On PresetThis open collector output line J3-6, provides a logic low pulse ( Preset-On -Power ) to the user that ca

93on, it causes J3-6 ( Preset-On-Power ) to be low thus, if used, can initialize or delay a customer's system operation.AC Dropout Buffer Circuit

94If it is necessary to have all the supplies come up simultaneously after a system shutdown, follow this procedure:a. First bring the INHIBITREMOTE

95TroubleshootingBefore attempting to troubleshoot the 002 Option Board, ensure that the fault is with the option itself and not with the mainpower su

96Figure A-11. Troubleshooting Current Programming of CV ModeFigure A-12. Troubleshooting Current Programming of CC ModeTroubleshooting Status Indic

97Figure A-13. Troubleshooting Status IndicatorsTo check Mode CV proceed as follows:a. Using test set-up, Figure A-13, connect to end of 2KΩ resist

98c. Turn on power supply.d. DVM should read approximately 5Vdc.e. Set voltage and current controls of power supply to maximum.f. Decrease resista

99Table A-3. Replacement PartsREF. DESIG. MODEL NO. PART NO. DESCRIPTIONA7 All 5060-2854 Opt. 002 Interface BoardC1,2 All 0180-0230fxd elect. 1µF 20%