Manuals / Fluke / Home Audio / Stereo Amplifier

Fluke 5725A instruction manual AC Line Voltage Selection Section

Models: 5725A

1 208

Download 208 pages 33.86 Kb

Page 107

Theory of Operation 4

Detailed Circuit Description

4-60. AC Line Voltage Selection Section

In addition to the primary power switch, S401, this section contains three line-voltage selection switches, S402 through S404. These three switches allow the 5725A to be set to eight nominal ac line voltage levels, each with a 10% tolerance.

Thermistors RT401 and RT402 have negative temperature coefficients, and limit inrush current at power-up. Relay K401 provides a pair of shunt switches to bypass thermistors after about a half second. This allows greater efficiency than with thermistors alone, and the use of thermistors allows operation if the relay fails. CR401 through CR404 and C401 form an unregulated power supply that is not isolated from ac line power for controlling K401. R401, R402, and C402 provide a time delay that prevents Q401, and hence K401 from switching before the effective power supply capacitance is sufficiently charged.

Metal Oxide Varistor RV401 prevents high voltage transients on the ac line from reaching the transformer by clamping voltages above 275V ac.

4-37

Image 107

Fluke 5725A instruction manual AC Line Voltage Selection Section

Contents

Amplifier 5725AInstruction Manual LIMITED WARRANTY AND LIMITATION OF LIABILITY Table of Contents Theory of Operation 5725ACalibration and Verification MaintenanceTroubleshooting Parts Lists Schematic DiagramsHow to Obtain Parts Service CentersTitle List of TablesTable 8-15 5725ATitle List of FiguresFigure Instruction Manual 5725Aviii Bescheinigung des Herstellers/Importeurs Interference InformationDeclaration of the Manufacturer or Importer Page Terms in this Manual OPERATOR SAFETY SUMMARYHIGH VOLTAGE LETHAL VOLTAGEUse the Proper Fuse Symbols Marked on EquipmentPower Source Use the Proper Power CordUse Care When Servicing With Power On SERVICING SAFETY SUMMARYFOR QUALIFIED SERVICE PERSONNEL ONLY Do Not Service AloneNever Accept Ordinary and General Tests for Death FIRST AID FOR ELECTRIC SHOCKFree the Victim From the Live Conductor Get HelpChapter Introduction and SpecificationsInstruction Manual 5725A1-1.Introduction 1-2.Where to Go From Here 1-6.5700A/5720A Series II Manual Set 1-3.How to Use the Manuals1-4.5725A Getting Started Manual 1-5.5725A Instruction Manual1-10.5700A/5720A Series II Service Manual 1-11.Specifications5720A 1-12.DC Voltage SpecificationsIntroduction and Specifications DC Voltage SpecificationsInstruction Manual 5725A5700A 5700AOvershoot 5 % Introduction and SpecificationsDC Voltage Specifications NotesInstruction Manual 1-13.AC Voltage Specifications5725A 5720A95 % Confidence Level Introduction and SpecificationsAC Voltage Specifications 5720A99 % Confidence Level 5725A5700A Instruction Manual95% Confidence Level Introduction and SpecificationsAC Voltage Specifications 5700ARange 5725AInstruction Manual Figure 1-1. Volt-HertzCapability Introduction and SpecificationsAC Voltage Specifications 5725A Amplifier5720A 1-14.Resistance Specifications5725A 5720A5700A Introduction and SpecificationsResistance Specifications 5700AInstruction Manual 5725AI < IL Introduction and SpecificationsResistance Specifications Table 1-12.Current Derating Factors5720A 95% 1-15.DC Current Specifications5725A 5720A 99%5700A Introduction and SpecificationsDC Current Specifications 5700AOvershoot: <5 % 5725AInstruction Manual Notes5720A 99% 1-16.AC Current SpecificationsIntroduction and Specifications AC Current Specifications95 % Confidence Level 5725A5720A 95% Instruction Manual99 % Confidence Level Introduction and SpecificationsAC Current Specifications 5700A95 % Confidence Level 5725A5700A Instruction ManualStability ±1 C Note Introduction and SpecificationsAC Current Specifications Instruction Manual 5725A1-28 Guard isolation: 20 1-18.General SpecificationsIntroduction and Specifications General Specifications5725A 1-19.Auxiliary Amplifier Specifications5220A AC Current, 180-dayspecifications Temperature Coefficient for 0-18C and 28-50CPage InstallationChapter TitleInstruction Manual 5725AInstallation 2-1.Introduction2-2.Unpacking and Inspection VOLTAGE/CURRENT 5725AInstruction Manual TYPEService Information 2-3.Service Information2-4.Placement and Rack Mounting 2-5.Cooling ConsiderationsFigure 2-2.Correct Way to Dress Interface Cable 2-6.Connecting to the 5700A CalibratorSelecting Line Voltage 2-7.Selecting Line Voltage2-8.Accessing the Fuse Connecting to Line Power 2-9.Connecting to Line PowerInstruction Manual 5725AChapter Operating NotesInstruction Manual 5725AOperating Notes 3-1.Introduction5725A 3-2.Front Panel FeaturesFigure 3-1.Front Panel Features POWER5725A STANDBY Indicator A B C D E F G HRear Panel Features Table 3-1.Front Panel FeaturesInstruction Manual 3-3.Rear Panel FeaturesFigure 3-2.Rear Panel Features 5725A5700A CALIBRATOR Connector A B C D E F G HTable 3-2.Rear Panel Features CALIBRATION Switch3-5.Warm Up 3-4.Turning on the 5725A Amplifier3-7.Standby 3-6.5725A Operating Functions and ModesVoltage Standby 5725A Operating Functions and Modes Current StandbyOperating Notes Voltage Operate 3-10Conditions That Activate the 5725A 3-11Current Operate Operating Notes3-12.Conditions That Activate the 5725A Chapter Theory of OperationHigh Voltage Amplifier Feedback High Voltage Sense Assembly A6High Voltage Amplifier A3 High Voltage Heat Sink Assemblies4-2.Overall Functional Description 4-1.IntroductionInstruction Manual Figure 4-1.5725A Overall Block Diagram5725A 4-3.1100V AC Range Functional Description 4-4.11A Range Functional Description 4-8.Voltage Standby 4-5.Operation in the 11A DC Range4-6.Operation in the 11A AC Range 4-7.Voltage and Current Standby Modes4-11.Description of the Out-GuardLines 5725A Side 4-10.How the 5700A and 5725A Communicate4-12.Description of the In-GuardLines 4-13.Functional Summaries by Assembly 4-14.Detailed Circuit Description 4-15.Interconnect Assembly A14-16.Power Supply Assembly A4 Table 4-1.Internal Fuse Data 4-17.High Voltage Supply SectionASSEMBLY REF DES4-18.Switching Section 4-20.System Supply Section 4-19. Current-LimitSection4-24.External RAM 4-22.Digital Assembly A54-21.Fan Supply Section 4-23.Microcomputeraq19f.eps Figure 4-2.Digital Assembly Block DiagramTheory of Operation Detailed Circuit Description4-29.Led Driver 4-26.EEROM4-27.Data Latch 4-28.Strobe Lines4-31. Break-DetectCircuitry 4-32.Power Up and Reset Circuitry4-33.Watchdog Timer 4-34.Current Amplifier Assembly A2aq20f.eps 5725AInstruction Manual 4-35.Error Amplifier Section 4-37.Monitor Section 4-36.Output Stage Section4-39.Power Supply Section 4-38.Control and Switching Section4-41.Input Amplifier 4-40.High Voltage Amplifier A3aq22f.eps Theory of OperationDetailed Circuit Description 4-44.Input Clamp 4-42.Integrator4-43.Window Comparator 4-48.High Voltage Heat Sink Assemblies 4-45.Transconductance and Cascode Stage4-46.Midstage 4-47.Midstage -400VFilter4-50.Autobias Sense Circuit 4-49.Autobias Current SourceTable 4-2.Signal Transformer Usage 4-52.Signal Transformers4-53.Temperature Monitoring 4-51.High Voltage Amplifier Feedback4-54.High Voltage Sense Assembly A6 aq21f.eps Theory of OperationDetailed Circuit Description 4-55.Sense Amplifier Section ±3.2V during calibration PHYSICAL 4-56.Analog Monitor SectionSIGNAL STANDBY VOLTAGE LIMITS14-57.Serial Interface/Guard Crossing Section 4-58.Analog Input Switching Section4-59.Control Section 4-60.AC Line Voltage Selection Section Instruction Manual 5725AChapter Calibration and VerificationInstruction Manual 5725ACalibration and Verification 5-2.Where to Find Further Information5-1.Introduction Instruction Manual 5725AA Message From static awarenessFluke Corporation 6.DO NOT SLIDE S.S. DEVICES OVER ANY SURFACE Chapter MaintenanceInstruction Manual 5725A6-2.Replacing the Fuse 6-1.Introduction6-3.Cleaning the Air Filter General Cleaning 6-4.General Cleaning6-5.Cleaning PCA’s B. BOTTOM VIEW 6-6.Access ProceduresFigure 6-3.Assembly Location Diagram A. TOP VIEW6-7.Initial Access Procedure HIGH VOLTAGE 6-9.Accessing the Digital Assembly A5 6-8.Accessing the Power Supply Assembly A4Instruction Manual WHEN REINSTALLING DIGITAL ASSEMBLYFigure 6-5.Accessing the Digital Assembly 5725A6-10.Accessing the Current Amplifier Assembly A2 Figure 6-6.Correct Way to Dress Cables 6-11.Accessing the High Voltage Amplifier A36-12.Accessing the High Voltage Sense Assembly A6 6-14.Accessing the Interconnect Assembly A1 6-15.Enabling Front or Rear Binding Posts 9.Reinstall the top cover Chapter Troubleshooting5725A 7-1.Introduction 7-2.5725A Fault Codes7-3.Self Diagnostics MESSAGE Table 7-1.5725A Fault CodesFAULT 5725A Instruction ManualMESSAGE Self DiagnosticsTable 7-1.5725A Fault Codes cont FAULT7-4.Manual Tests for Fault Isolation MESSAGE Manual Tests for Fault IsolationTable 7-2.Analog Monitor Faults FAULT NO7-9. Reduced-VoltageTroubleshooting Mode Testing the Power Supply By Itself 7-10.Testing the Power Supply By ItselfInstruction Manual 5725AChapter List of Replaceable PartsInstruction Manual 5725A8-3.Manual Status Information 8-2.How to Obtain Parts8-5.Service Centers 8-1.Introduction5725A 8-6.Parts ListsAssembly Name Table 8-2.Final AssemblyList of Replaceable Parts Parts ListsTable 8-2.Final Assembly cont TM1 W1 W13 W14 W15 W16 W44 XF501 Table 8-2.Final Assembly cont5725A Instruction Manualaq24f.tif Parts ListsFigure 8-1.Final Assembly List of Replaceable Partsaq25f.tif Figure 8-1.Final Assembly cont5725A Instruction Manualaq26f.tif Parts ListsFigure 8-1.Final Assembly cont List of Replaceable Partsaq27f.tif Figure 8-1.Final Assembly cont5725A Instruction Manualaq28f.tif Parts ListsFigure 8-1.Final Assembly cont List of Replaceable Partsaq29f.tif Figure 8-1.Final Assembly cont5725A Instruction Manualaq30f.tif Parts ListsFigure 8-1.Final Assembly cont List of Replaceable Partsaq31f.tif Figure 8-1.Final Assembly cont5725A Instruction ManualTable 8-3.A1 Interconnect PCA Parts ListsList of Replaceable Parts Figure 8-2.A1 Interconnect PCA 5725AInstruction Manual 5725A-1611Table 8-4.A2 Current Amplifier PCA Parts ListsList of Replaceable Parts Reference Description Designator 5725AInstruction Manual Table 8-4.A2 Current Amplifier PCA contR233,R237,R238 R273 R243,R244 R247,R248 Parts ListsList of Replaceable Parts Table 8-4.A2 Current Amplifier PCA contaq37f.eps 5725A5725A-1650 Figure 8-3.A2 Current Amplifier PCATable 8-5.A3 High Voltage Amplifier PCA Parts ListsList of Replaceable Parts Table 8-5.A3 High Voltage Amplifier PCA cont 5725AR640,R642 R641,R648 R643 R647 R651 R654,R661,R684 Parts ListsList of Replaceable Parts Table 8-5.A3 High Voltage Amplifier PCA contFigure 8-4.A3 High Voltage Amplifier PCA 5725AInstruction Manual 5725A-1661Reference Designator Parts ListsTable 8-6.A4 Power Supply PCA List of Replaceable PartsReference Table 8-6.A4 Power Supply PCA cont5725A Instruction ManualR351 R355 R361,R362 Parts ListsTable 8-6.A4 Power Supply PCA cont List of Replaceable Parts5725A-1631 Figure 8-5.A4 Power Supply PCA5725A Instruction ManualReference Parts ListsList of Replaceable Parts Table 8-7.A5 Digital PCAFigure 8-6.A5 Digital PCA 5725AInstruction Manual 5725A-1650Table 8-8.A6 High Voltage Sense PCA Parts ListsList of Replaceable Parts Table 8-8.A6 High Voltage Sense PCA cont 5725AInstruction Manual R154 R155 R156,R158,R168 R173 R162 R171 R172,R175 Parts ListsList of Replaceable Parts Table 8-8.A6 High Voltage Sense PCA contFigure 8-7.A6 High Voltage Sense PCA 5725AInstruction Manual 5725A-1601List of Replaceable Parts Parts ListsTable 8-9.A12 Transformer Enclosure Assembly aq32f.tif Figure 8-8.A12 Transformer Enclosure Assembly5725A aq33f.tif Parts ListsList of Replaceable Parts aq34f.tif 5725AInstruction Manual aq35f.tif Parts ListsList of Replaceable Parts Figure 8-9.A30 Inductor PCA 5725AInstruction Manual Table 8-10.A30 Inductor PCAChapter Schematic Diagrams5725A aq48f.eps Schematic Diagrams5725A-1611 Figure 9-1.A1 Interconnect PCAFigure 9-1.A1 Interconnect PCA cont 5725AInstruction Manual Figure 9-1.A1 Interconnect PCA cont Schematic Diagrams5725A-1650 5725AInstruction Manual Figure 9-2.A2 Current Amplifier PCAFigure 9-2.A2 Current Amplifier PCA cont Schematic DiagramsFigure 9-2.A2 Current Amplifier PCA cont 5725AInstruction Manual Figure 9-2.A2 Current Amplifier PCA cont Schematic Diagrams5725A-1661 5725AInstruction Manual Figure 9-3.A3 High Voltage Amplifier PCAFigure 9-3.A3 High Voltage Amplifier PCA cont Schematic DiagramsFigure 9-3.A3 High Voltage Amplifier PCA cont 5725AInstruction Manual aq59f.eps Schematic DiagramsFigure 9-4.A4 Power Supply PCA Instruction Manual Figure 9-4.A4 Power Supply PCA cont5725A Figure 9-4.A4 Power Supply PCA cont Schematic DiagramsTYPICAL COMMUNICATIONS ACTIVITY AT PINS 12 AND 13 OF U5075725A Instruction ManualFigure 9-5.A5 Digital PCA cont Schematic DiagramsVOLTAGE STANDBY 5725AInstruction Manual STANDBYFigure 9-6.A6 High Voltage Sense PCA cont Schematic DiagramsFigure 9-6.A6 High Voltage Sense PCA cont 5725AInstruction Manual Figure 9-6.A6 High Voltage Sense PCA cont Schematic DiagramsFigure 9-6.A6 High Voltage Sense PCA cont 5725AInstruction Manual aq45f.eps Schematic DiagramsFigure 9-7.A12 Transformer Enclosure Assembly Instruction Manual 5725AIndex 5725A Page 5725A