Agilent Technologies 5962-8200 service manual CV/CC Status Annunciators Troubleshooting

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3 - Troubleshooting

E221	Front Panel comm UART framing error	A3 Front Panel/Display Bd
E222	Front Panel comm UART parity error	A3 Front Panel/Display Bd
E223	Front Panel firmware input buffer overrun	A3 Front Panel/Display Bd

CV/CC Status Annunciators Troubleshooting

The CV/CC annunciators are particularly helpful when troubleshooting a unit with no output voltage or current. If the unit has passed self test the programming DAC circuits on the A2 circuit board are probably working properly. If either the CV or CC annunciators is on then the problem is in either the CV or CC control circuits located on the A1 Main board. If UNR is indicated then neither the voltage nor the current circuits are in control and the problem would be in the main power transformer or the driver or output regulator stages circuits, also on A1 but after the gating diodes.

Bias and Reference Supplies

Before troubleshooting any circuit check the bias and/or reference voltages to make sure that they are not the cause. Table 3-3 lists the bias and reference voltage test points for the A1 Main Control , A2 Interface, and the A3 Front Panel/Display boards. Unless otherwise noted, all voltages are measured with respect to secondary common (R431-3) with no load on the supply. See Figure 6-1 for test point locations.

Table 3-3. Bias and Reference Voltages

Bias	Test Point		Measurement
+5V primary 1	A1	E320(Red wire)	+5V	+/- 0.15V
+5V primary (unreg) 1	A1	E3321(White wire)	+5V
+5V secondary 2	A1	R423 (jumper)	+5V	+/- 0.2V
+15V secondary 2	A1	R419 (jumper)	+15V +/- 0.6V
-15V secondary 2	A1	R422 (jumper)	-15V +/- 0.6V
6611C +Rail 3	A1	Main Heat Sink	+20V		+/- 10% (50mV P/P)
6612C +Rail 3	A1	Main Heat Sink	+32V		+/- 10% (120mV P/P)
6613C +Rail 3	A1	Main Heat Sink	+81V		+/- 10% (300mV P/P)
6614C +Rail 3	A1	Main Heat Sink	+130V +/- 10% (400mV P/P)
-Rail 3	A1	D307 Anode	-6.8 to - 9.1V (100mV P/P)

1Measured with respect to Primary common (Black wire at A1 E324).

2Measured with respect to Secondary common (R431-3).

3Measured with respect to - Output at nominal ac input line voltage.

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Contents Agilent Part No Microfiche No September Warranty Information CertificationSafety Summary Before Applying PowerSafety Symbol Definitions Symbol DescriptionPrinting History Instrument IdentificationTable of Contents Post-repair Calibration Initialization ROM UpgradeDisassembly Procedures IntroductionPage Related Documents Safety ConsiderationsOrganization ChapterManual Revisions RevisionsElectrostatic Discharge Firmware RevisionsIntroduction Test Equipment RequiredType Specifications Recommended Model Test SetupMeasurement Techniques Test Setup Electronic LoadCurrent-Monitoring Resistor Operation Verification TestsPerformance Tests ProgrammingVoltage Programming and Readback Accuracy CV SetupConstant Voltage CV Tests CV Load EffectCV Source Effect Transient Recovery TimeCV Noise Pard Constant Current CC Tests CC SetupCurrent Programming and Readback Accuracy Current Sink -CC Operation Low Range Current Readback AccuracyCC Load and Line Regulation CC Load EffectCC Source Effect CC Noise PardPerformance Test Equipment Form Constant Current Tests Current Programming and Readback Load Effect Source Effect Pard Ripple and NoiseTransient Response Current Sink @ -3A Readback MA Range Current ReadbackSource Effect Vout − Vout −Load Effect Vout − Vout + 2.0mV Iout −Iout − Iout + 2.2 mA Vout + 4 mVIout − Iout + 0.2 mA Current Sink @ -0.6A Readback Iout −Iout − Iout + 1.1 mA Load Effect Vout − Vout + 5 mVIout − Iout + 0.1 mA Current Sink @ -0.3A Readback Iout −Page Troubleshooting Test Equipment Required for Troubleshooting Overall TroubleshootingFlow Charts Type Purpose Recommended ModelSheet 1. Troubleshooting Flowchart Sheet 2. Troubleshooting Flowchart Sheet 3. Troubleshooting Flowchart Sheet 4. Troubleshooting Flowchart Self-Test Error Codes/Messages Specific Troubleshooting ProceduresPower-on Self-test Failures Error Code Description Probable CauseBias and Reference Voltages CV/CC Status Annunciators TroubleshootingBias and Reference Supplies Bias Test Point MeasurementJ307 Voltage Measurements Voltage Measurements at J207 A2 Interface to A1 Main boardDisabling Protection Features Manual Fan Speed ControlCalibration Password Inhibit Calibration SwitchPost-repair Calibration Initialization ROM UpgradeUpgrade Procedure Identifying the FirmwareDisassembly Procedures List of Required ToolsA2 Interface Board, Removal and Replacement Cover, Removal and ReplacementFront Panel Assembly, Removal and Replacement T1 Power Transformer, Removal and Replacement A3 Front Panel Board, Removal and ReplacementA1 Main Control Board Line Voltage Wiring Power Supply Interface signals Interface SignalsConnector Signal Description Primary Interface A3 Front Panel CircuitsA2 Interface Circuits Secondary InterfacePower Circuits A1 Main Board CircuitsControl Circuits Principles of Operation Page Chassis, Electrical Designator PartNumber Qty DescriptionReplaceable Parts List Mechanical Parts Identification Chassis, Mechanical MP9Diagrams Diagrams A2/A3 Boards Block Diagram Bias CircuitsIndex Index