Theory of Operation, 36. Current Assembly Calibration | Fluke 5720A

ahp031f.eps

Theory of Operation 2

Analog Section Detailed Circuit Description

ahp031f.eps

Figure 2-36. Current Assembly Calibration

2-127

Image 189

Fluke 5720A Theory of Operation, Analog Section Detailed Circuit Description, 36. Current Assembly Calibration

Contents

Service Manual 5700A/5720A SeriesMulti-Function Calibrator 5/94 LIMITED WARRANTY & LIMITATION OF LIABILITY Interference Information Declaration of the Manufacturer or ImporterBescheinigung des Herstellers/Importeurs Page HIGH VOLTAGE OPERATOR SAFETY SUMMARYLETHAL VOLTAGE Terms in this Manual Power Source Symbols Marked on EquipmentUse the Proper Power Cord Use the Proper Fuse FOR QUALIFIED SERVICE PERSONNEL ONLY SERVICING SAFETY SUMMARYDo Not Service Alone Use Care When Servicing With Power On Free the Victim From the Live Conductor FIRST AID FOR ELECTRIC SHOCKGet Help Never Accept Ordinary and General Tests for Death Introduction and Specifications Table of ContentsTitle Page Theory of Operation 5700A/5720A Series ±PA Supplies Digital Control How the DAC is Used in Calibration Calibration and Verification Ohms Cal Assembly A9Calibration Procedure Troubleshooting MaintenanceRear Panel Assembly Access Using Remote Commands Reserved for Servicing List of Replaceable Parts Schematic Diagrams viii List of Tables Unregulated Supplies from the Filter Assembly Test Record for Flatness Check of the AC 2 mV Range A16A1 Power Amplifier Digital Control SIP PCAA11A2 DAC Buffered Reference SIP PCA A13A1 Oscillator Wideband SMD PCA 5700A/5720A Series List of Figures Ohms Main Assembly Simplified Schematic A15 High Voltage/High Current PCA Power Amplifier with Calibrator Set to 22V at 1 kHz 5700A/5720A Series Chapter Introduction and Specifications 5700A/5720A Series II Calibrator Service Manual 1-1. Introduction 1-4. How to Use this Manual 1-2. Contacting Fluke1-3. About this Manual 1-6. Wideband AC Voltage Module Option 5700A-03 1-5. Additional Instruction Manuals∙ 5700A/5720A Series II Getting Started Manual PN ∙ 5700A/5720A Series II Operator Reference Guide PN 1-9. Support Equipment and Services 1-7. Auxiliary Amplifiers1-8. 5725A Amplifier 1-10. 732B Direct Voltage Reference Standard 1-11. 732B-200 Direct Volt Maintenance Program U.S.A. Only1-12. 742A Series Resistance Standards 1-13. Wideband AC Module Option 5700A-03 Calibration Support 1-15. The Components of the 5700A/5720A Series II Calibrator 1-14. Service Centers Calibrating the 5700A/5720A Series II Calibrator 1-16. Calibrating the 5700A/5720A Series II Calibrator 1-18. Establishing Traceability 1-17. The Calibration Process 1-20. Calibration Check 1-21. Developing a Performance History1-19. Calibration Reports 1-25. Specification Confidence Levels 1-24. Specifications1-26. Using Absolute and Relative Uncertainty Specifications 1-22. Range Calibration Specifications 1-27. Using Secondary Performance Specifications 5720A 1-28. DC Voltage Specifications99 % Confidence Level 95% Confidence Level 5700A DC Voltage Specifications99 % Confidence Level 95 % Confidence Level Overshoot 5 % Common mode rejection 140 dB, DC to 400 Hz AC Voltage Specifications 1-29. AC Voltage Specifications See Volt-Hertz capability in Figure 99 % Conf idence Level ± 5 C from calibration temperature90 Days 95% Confidence Level ± ppm output + μV 0-10 C and±ppm output + mV 5725A Amplifier Figure 1-2. Volt-Hertz CapabilitydBm reference 600 Ω 1-30. Resistance Specifications Resistance Specifications99% Confidence Level 5700A/5720A Series II Calibrator Characterized ±1 C Notecompensation active I IL Table 1-13. Current Derating Factors DC Current Specifications 1-31. DC Current Specifications5720A 99% 5720A 95% 5700A/5720A Series II Calibrator Overshoot 5 % 1-32. AC Current Specifications AC Current Specifications 5700A/5720A Series II Calibrator 95 % Confidence Level ± ppm output + nA Temperature Coefficient NoteV rms maximum load for full accuracy Wideband AC Voltage Option 5700-03 Specifications 1-33. Wideband AC Voltage Option 5700-03 SpecificationsTable 1-22. Wideband AC Voltage Option 5700-03 Specifications 1-35 1-34. General Specifications Guard isolation 20Size Auxiliary Amplifier Specifications 1-35. Auxiliary Amplifier Specifications5220A AC Current, 180-day specifications 5205A 220V - 1100 V ac, 0 V - 1100 V dc Overshoot 10 % 5700A/5720A Series II Calibrator Theory of Operation 2-36 Theory of Operation 2-155 2-2. Calibrator Overview 2-1. Introduction2-3. Internal References 2-4. Hybrid Reference Amplifiers 2-7. Digital Section Overview 2-8. Analog Section Overview2-6. Digital-to-Analog Converter DAC Figure 2-1. Digital Section Block Diagram Analog Section Overviewahp003f.eps 2-10. DC Voltage Functional Description 2-9. Functional Description Presented by Output Function ahp33f.eps Figure 2-2. Analog Section Block Diagram, Part 5700/5720A Series II Calibrator Figure 2-3. Analog Section Block Diagram, Part 2-11. AC Voltage Functional Description 2-12. Wideband AC V Functional Description Option 2-13. DC Current Functional Description2-14. AC Current Functional Description 2-17. Digital Motherboard Assembly A4 2-16. System Interconnect Detailed Circuit Description2-15. Ohms Functional Description 2-19. Analog Motherboard Assembly A3 2-18. Transformer Assembly A22 Functional Description Presented by 0utput Function Figure 2-4. System Interconnectionsahp35f.eps Figure 2-4. System Interconnections cont Table 2-1. Analog Motherboard Connectors Motherboard ConnectorConnected to Assembly 2-22. Filter PA Supply Assembly A18 2-21. Rear Panel Assembly A212-24. Digital Power Supply Assembly A19 2-23. Digital Section Detailed Circuit Description 2-26. ±12V Power Supplies 2-25. +5V Power Supply2-27. +35V Power Supply Digital Section Detailed Circuit Description 2-29. +35V and +75V Shut-Down Circuit 2-28. +75V Power Supply 2-30. CPU Central Processing Unit Assembly A20 2-31. Power-Up and Reset Circuit2-32. Clock Generation ahp004f.eps Figure 2-5. CPU Assembly Block Diagram Function Table 2-3. CPU Acronym Glossary 2-34. Address Decoding and DTACK Data Acknowledge 2-33. Watchdog TimerTable 2-4. CPU Memory Map Chip Select 2-35. Interrupt Controller 2-37. RAM Random-Access Memory2-36. Glue Logic 2-38. ROM Read-Only Memory 2-39. Electrically-Erasable Programmable Read-Only Memory EEPROM 2-40. DUART Dual Universal Asynchronous Receiver/transmitter Circuit2-41. Clock/Calendar Circuit 2-43. CPU to Rear Panel Interface 2-42. Clock Filter Circuit2-44. CPU to Front Panel Interface 2-45. Fan Monitor 2-47. Clock Regeneration Circuitry 2-46. Front Panel Assembly A22-48. Refresh Failure Detect Circuitry 2-49. Decoding and Timing Circuitry êêêêêêê 2-50. Control Display Circuitry 2-51. Output Display Circuitry 2-53. Knob Encoder Circuitry 2-52. Keyboard Scanner Circuitry 2-54. Led Circuitry 2-55. Keyboard Assembly A1 2-57. Filter/PA Supply A18, Low-voltage Filter/Regulator Section 2-56. Analog Section Detailed Circuit Description 2-59. Unregulated LH Supplies 2-58. Unregulated OSC Supplies2-60. Unregulated S Supplies 2-61. Triac Circuit 2-65. Filter/PA Supply A18, Power Amplifier Output Supply Section 2-64. FR2 Supplies2-66. ±PA Supplies Digital Control ahp005f.eps Figure 2-6. Power Amplifier Output Supply Simplified Schematic 2-68. +PA and -PA Supplies 2-67. ±250V and ±500V Supplies2-69. ±PA Supply Current Limit ∙ PA CT is the center tap 2-70. Regulator/Guard Crossing Assembly A17 2-71. Voltage Regulator Circuitry2-72. Regulated OSC Supplies 2-74. Regulated S Supplies 2-73. Regulated LH Supplies+15 OSC -15 OSC +5RLH +5LH -5LH +44S -44S +17S -17S 15S +30FR1 +30FR2 +15V +5.975V +5.1V +44.15V +17.000V -17.000V +30.96V +30.96V 2-76. FR2 Supply 2-75. FR1 Supply 2-79. Inguard Memory Configuration 2-77. Guarded Digital Control Circuitry2-78. Inguard CPU Memory Map 2-82. Power-Up and Reset Circuitry 2-81. Inguard Watchdog Timer2-80. Inguard Clock Circuit 2-83. Break Detection 2-87. Switch Matrix Assembly A8 2-85. Interface to Guarded Digital Bus2-86. Inguard CPU Interrupts 2-88. Switch Matrix Digital Control System Interconnection Detailed Circuit Description Figure 2-7. Switch Matrix Assembly Simplified Schematic 3. Apply 7V to the relay coils by setting PC5 high 2-89. Switch Matrix Operation 11V DC and 22V DC Ranges ahp006f.eps Figure 2-8. Switch Matrix Configuration for 11V DC and 22V DC Ranges 2-91. Switch Matrix Operation 220V AC and DC Ranges 2-90. Switch Matrix Operation 2.2V AC and 22V AC Ranges ahp007f.eps Figure 2-9. Switch Matrix Configuration for 2.2V and 22V AC Ranges ahp008f.eps Figure 2-10. Switch Matrix Configuration for 220V DC and AC Ranges 2-92. Switch Matrix Operation 2.2V DC Range ahp009f.eps Figure 2-11. Switch Matrix Configuration for 2.2V DC Range 2-94. Switch Matrix Operation 220 mV DC Range 2-93. Calibration of the 2.2V RangeTo calibrate the offset ahp010f.eps Figure 2-12. Calibration of the 2.2V DC Range ahp011f.eps Figure 2-13. Switch Matrix Configuration for 220 mV DC Range 2-95. Switch Matrix Operation 220 mV AC Range 2-96. Switch Matrix Operation 2.2 mV and 22 mV AC Ranges2-97. Calibration of the mV Ranges ahp012f.eps Figure 2-14. V AC, 2.2 mV AC, and 22 mV AC Range ahp013f.eps Figure 2-15. Divider Calibration 2-98. Internal CAL Zero Amplifier ahp014f.eps Figure 2-16. Divider Gain Calibration 2-99. Switch Matrix 5725A Amplifier Interface 2-100. DAC Assembly A112-101. Basic DAC Theory of Operation 0.1 x 13V + 0.5 x 0.78 mV = ahp015f.eps Figure 2-17. DAC Assembly Simplified Schematic 2-102. DAC Assembly Digital Control 2-103. DAC Assembly Reference CircuitryProgrammable Peripheral Interface IC U31 is the heart of this circuit 2-104. Duty-Cycle Control Circuit 2-105. DAC Filter Circuit 2-106. DAC Output StageREFCOM 2-108. Linearity Control Circuit 2-107. Sense Current Cancellation Circuit 2-110. DAC Output Switching 2-109. Negative Offset Circuit2-111. DAC Buffered Reference Sip 2-112. Calibration Hardware 2-113. ADC Amplifier2-114. ADC Input Selection ∙ ADC reference voltage ∙ ADC dac ∙ ADC comparator/amplifier 2-115. ADC Circuit ahp016f.eps Figure 2-18. ADC Circuit Measurement Functions 2-117. DAC Assembly Calibration 2-116. How the DAC is Used in CalibrationINPUT 2-118. Oscillator Section Overview 2-119. Oscillator Control Assembly A12 2-121. Oscillator Input Switching 2-122. Sense Current Cancellation2-120. Oscillator Control Digital Control 2-123. Averaging Converter 2-124. Error Integrator2-125. Three-Pole Filter 2-126. Analog Amplitude Control Loop ahp017f.eps Figure 2-19. Oscillator Control Analog Control Loop 2-127. AC/DC Thermal Transfer Circuit ahp018f.eps Figure 2-20. AC/DC Thermal Transfer Circuit 2-128. Oscillator Calibration 2-129. AC/DC Frequency Response Characterization 2-130. Oscillator Output Assembly A13 ahp019f.eps Figure 2-21. Quadrature RC Oscillator Circuit 2-132. Quadrature RC Oscillator 2-131. Oscillator Output Digital Control 2-133. Oscillator Amplitude Control 2-134. Phase−locked Loop 2-135. 2.2V and 22V Range Output Amplifier 2-136. Oscillator Wideband Smd Assembly A13A1 2-138. Phase Shifter 2-139. Power Amplifier Assembly A162-137. Output Stage 1. Write the proper data for these relays to port A of the 82C55 U11 2-140. Power Amplifier Digital Control Sip Assembly A16A1 2-142. +PA and -PA Supplies 2-141. PA Common Circuitry2-143. PA Input Stage ∙ ±185V ∙ ±365V 2-145. PA Output Stage 2-144. PA Mid Stage 2-146. PA Sense Current Cancellation Circuitry 2-147. PA in Standby2-148. PA Operation 220V DC Range ahp020f.eps Figure 2-22. Power Amplifier Simplified Schematic 2-149. PA Operation 220V AC Range 2-150. High Voltage Assembly Support Mode2-151. High Voltage AC 1100V Range 2-152. High Voltage DC 1100V Range and Current 2.2A Range 2-154. PA Calibration 2-153. 220V DC Internal Calibration Network ahp021f.eps Figure 2-23. Power Amplifier DC Calibration Network Power Amplifier dc gain of approximately -20 is calibrated next. The Power Amplifier is configured as in the 220V dc operation, except the input is connected to the DAC’s 6.5V reference BRF6 and BSRF6 by U2C and U2D respectively. The resulting -130V at the Power Amplifier output is connected to the 175 kΩ end of the internal cal resistor network by relay K3. The 25 kΩ end of this network is connected to DAC OUT HI and DAC SENSE HI by relay K1. The output of the internal cal amplifier is connected to the DAC’s adc circuit as in the previous steps, and the DAC OUTPUT is adjusted until checkpoint is measured by the adc circuit. Since the exact attenuation of the resistor networks is already known, the exact Power Amplifier output voltage can be calculated. This in turn gives the exact Power Amplifier dc gain, since the exact value of 6.5V reference BSRF6 is known f2-24.eps Figure 2-24. Power Amplifier Calibration AC Attenuator 2-156. 1100V AC Range 2-155. High Voltage Assemblies A14 and A15 ahp022f.eps Figure 2-25. High Voltage/High Current Assembly 1100V AC Range 2-158. HVDC Power Supply Filter Circuit 2-157. 1100V DC Range2-159. HV DC Output Series Pass and Current Limit Circuit ahp023f.eps Figure 2-26. High Voltage/High Current Assembly 1100V DC Range 2-161. 2.2A Range 2-160. DC HV Amplifier/AC Sense Buffer ahp024f.eps Figure 2-27. High Voltage/High Current Assembly 2.2A AC and DC Ranges 2-162. 2.2A Power Supply Filter Circuit 2-163. High Voltage Digital Control 2-165. Calibration of the AC Function 2-164. High Voltage Calibration ahp025f.eps Figure 2-28. High Voltage/High Current Assembly Calibration 2-167. High Voltage Magnitude Control 2-166. Calibration of the Current Function ahp026f.eps 2-168. Ohms Overview 2-170. Selection of Resistance Values 2-169. Ohms Main Assembly A10 ahp38f.eps Figure 2-30. Ohms Assemblies Simplified Schematic Figure 2-31. Ohms Main Assembly Simplified Schematic Analog Selection Detailed Circuit Descriptionahp39f.eps 2-173. Ohms Cal Assembly A9 2-171. Ohms Main Assembly Support of Current Function Calibration2-172. Ohms Digital Control 2-174. Ohms CAL Digital Control 2-175. 1, 1.9, and Short Resistance 2-176. Two-Wire Ohmmeter Compensation Circuit ahp027f.eps Figure 2-32. Two-Wire Lead Drop Compensation Circuit 2-178. High Side Cancellation 2-177. Two-Wire Compensation Power Supplies2-179. Low Side Cancellation 2-180. Ohms Calibration ahp028f.eps Figure 2-33. Calibration to an External 10 kΩ Standard 2-181. Calibrating to the External 10 KW Standard 2-182. Calibrating 10 KW and 19 KW 2-183. Calibrating 100 KW2-184. Completion of High Resistance Value Calibration The 10Ω, 19Ω, 100Ω and 190Ω resistance values are determined using 2V from the 2/5/10V source and using internal 101 divider Z5 in conjunction with the DAC. To get 2V, Q2 and Q3 are both turned on, which parallels both the 11.535 kΩ value and the 3.846 kΩ value with the 50 kΩ value. The lower voltage is required to lower the power dissipation in the resistors ahp029f.eps Figure 2-34. Ratio Calibration, 10 Ω From 100 Ω 2-185. Calibrating to the External 1W Standard 2-186. Current/High Resolution Oscillator Assembly Overview A7 2-187. Current Section 2-188. Current Input Switching ahp030f.eps Figure 2-35. Current Output Simplified Schematic 2-189. Complementary Drive Circuit 2-190. Transconductance Amplifiers2-191. Shunt Resistors 2-192. Feedback Loop 2-193. Current Output Switching2-194. Generation of the 2.2A Range Table 2-15. Relay Settings for Current Range Selection Range 2-195. Current Guard Buffer 2-198. Current Assembly Calibration2-196. Compliance Limiter 2-197. Current/Compliance Voltage Monitor ahp031f.eps Figure 2-36. Current Assembly Calibration ∙ 10.00 Hz to 119.99 Hz ∙ 0.1200 kHz to 1.1999 kHz 2-199. High-Resolution Oscillator Section 2-200. Reference Frequency Amp/Divider 2-201. Phase-Locked Loop 2-203. Hi-Res Output Switching 2-204. Rear Panel Assembly A212-202. 5-500k Output Divider 2-205. Rear Panel Power Supplies 2-206. Rear Panel Address Mapping∙ RPDUARTCS*, D00000-D0001F ∙ RPIEEECS*, D00020-D0002F 2-207. Clock Regeneration Circuit 2-208. IEEE-488 GPIB Interface2-209. RS-232C Interface 2-212. Phase Lock In/Variable Phase out 2-210. Auxiliary Amplifier Interface2-211. 5725A Interface 2-213. Rear Panel Relay Control 2-214. Rear Panel CPU InterfacePort A PA0-PA7 provides the input lines for relay driver U16 2-217. Wideband Oscillator Power Supplies 2-216. Wideband Oscillator Assembly A62-215. Wideband AC Module Option 2-218. Wideband Oscillator Digital Control 2-219. Phase-Locked Loop and Divider Circuit 2-221. Wideband Oscillator Filters 2-220. Amplitude Control Amplifier and X10 Wideband Amplifier Figure 2-37 is a simplified schematic for the Wideband Output assembly 2-222. Wideband Output Assembly A5 ahp032f.eps Figure 2-37. Wideband Output Assembly Simplified Schematic 2-223. Wideband Output Power Amplifier Circuit 2-224. Wideband Output Attenuators 2-225. Wideband Output RMS Sensor and Amplitude Control Circuit2-226. Wideband Output Overload Control Circuit 2-228. Wideband Output Calibration 2-227. Wideband Output Digital Control connector is connected back to the OUTPUT HI SENSE and OUTPUT LO SENSE binding posts 5700A/5720A Series II Calibrator Calibration and Verification 3-30 Calibration and Verification 3-1. Introduction 3-2. Accessing the Fuse Cleaning the Air Filter 3-3. Cleaning the Air Filter 3-4. Cleaning the Exterior 3-5. Calibration3-6. Calibrating the 5700A/5720A Series II to External Standards 3-8. When to Adjust the Calibrator’s Uncertainty Specifications 3-7. Calibration RequirementsCalibrating the 5700A/5720A Series II to External Standards 3-9. Calibration Procedure 5. Connect the 732B to the calibrator as shown in Figure 4. Enter the ambient temperature then press E. The display showsFigure 3-3. 732B External Calibration Connections 732B DC STANDARD IF3-5.EPS IF3-6.EPSIF3-7.EPS After a few seconds, the following display appears CALIBRATOR RESISTANCE STANDARDFigure 3-4. 742A-1 and 742A-10k External Calibration Connections F7-4.EPS 16. Set the rear panel CALIBRATION switch to NORMAL 3-10. Range Calibration 4. Press the “DC V” softkey to bring up the next menu shown below IF057.EPS PREV MENU Calibrating the Wideband AC Module Option 5700A-03 3-11. Calibrating the Wideband AC Module Option 5700A-03 2. Press the “Cal “ softkey to bring up the following menu 4. Press the “Gain” softkey to bring up the following display 3-12. Performing a Calibration Check Press Pto exit the calibration menus Figure 3-7. Overview of Verification Tests 3-13. Full Verification 3-14. Required Equipment for All Tests 3-15. Warm-up Procedure for All Verification Tests Equipment Table 3-2. List of Required Equipment for Main OutputApplication Equipment Required for Wideband Ac Module Option 5700-03 Verification 3-16. Resistance Verification Test 13. The low-value 1Ω, 1.9Ω, and 10Ω tests are summarized in Table 3-17. Two-Wire Compensation Verification 3-18. DC Voltage Verification Test 3-19. DC Voltage One-Tenth Scale Linearity Test 3-20. Direct Current Accuracy Verification Test 3-22. Output Level Tests For AC V Ranges 3-21. AC Voltage Frequency Accuracy Test Use Table 3-23 5720A or Table 3-24 5700A for the test records Table 3-8. 5790A Adjustment Counts 3-23. AC Current Test, 22 mA to 11A Ranges5790A Adjustment Counts 5700A/5720A Series II Output Level 1. Connect the equipment as shown in Figure 3-12A use the 2A shunt A. Alternating Current Test Setup, 22 mA to 2A Using 5790A Input Figure 3-12. Alternating Current Test SetupB. Alternating Current Test Setup, 10A Using 5790A Input 5790A Hi Output Lo 3-24. AC Current Test, 2 mA and 200 μA RangesMetal Film Resistor Mounted on Dual Banana Plug 200 Pomona Cable 1362-A-18 3-25. Rationale for Using Metal-Film Resistors to Measure AC Current Figure 3-14. Metal Film Resistor Equivalent CircuitFigure 3-15. Metal Film Resistor in Test Circuit 3-27. Wideband AC Voltage Module Output Verification 3-26. Wideband Frequency Accuracy Test Wideband Output Accuracy at 1 kHz Test 3-28. Wideband Output Accuracy at 1 kHz Test 3-29. Wideband Output Flatness Test 3-30. Wideband Flatness Calibration Procedure 3-32. DC Voltage Load Regulation Test 3-31. Optional Tests 3-33. DC Voltage Linearity Test 3-34. DC Voltage Output Noise 10 Hz to 10 kHz TestOptional Tests 2. Set the Oscilloscope Differential Amplifier controls as shown below 3-35. DC Voltage Output Noise 0.1 to 10 Hz Test 3-37. Wideband Distortion Testing3-36. AC Voltage Distortion Test WWarning 3-38. AC Voltage Overshoot Test 3-39. Minimum Use Requirements Minimum Use Requirements Minimum Use SpecificationsTable 3-15. Minimum Use Requirements Calibration Equipment 3-40. Determining Test Limits for Other Calibration Intervals 130 + 1000000*0.000000040/0.002=130 ppm + 20 ppm = 150 ppm 1Ω Std Res Value DMM Error1Ω Std Voltage Measured 1Ω Std Voltage Table 3-16. 5720A Resistance Test Record cont DMM UUT Res ValueUUT True Res Value UUT 1Ω Displayed Value Table 3-17. 5700A Resistance Test RecordUUT 1Ω Voltage UUT True Res Difference of Characterized to Nominal Value Table 3-17. 5700A Resistance Test Record cont Max Table 3-18. DC Voltage Test Record for 5720A Divider Setting5720A Range 5720A Output Table 3-19. DC Voltage Test Record for 5700A 5700A Range5700A Output Setting UUT ErrorError A+B Table 3-20. Direct Current Accuracy Test Record 5720A 5725A Amplifier DC Current Test Table 3-21. Direct Current Accuracy Test Record 5700ATest Limit 90-day ppm DC DMM Reading Table 3-23. 5720A AC Voltage Output Test Record Error Display ReadingOutput Level Output Level ErrorTable 3-23. 5720A AC Voltage Test Record cont Display Table 3-24. 5700A AC Voltage Output Test Record Table 3-25. AC Voltage 2 mV Range Test Record Table 3-24. 5700A AC Voltage Output Test Record contCharacterized 1.9 mV Reading Limits Calculated Error UUT Error DisplayTable 3-26. 5720A AC Current 20 mA to 10A Accuracy Test Record 2A, 200 mA, 20 mA and 10A Test Record Table 3-27. 5700A AC Current 20 mA to 10A Accuracy Test Record 2A, 200 mA, 20 mA and 10A Test Record 10A Only for 5725ASpecs ±ppm Spec ± ppm 90-day Table 3-28. 5720A AC Current 2 mA and 200 μA Accuracy Test Record5790A Transfer Spec ± ppm Test Limits ± ppm Frequency Hz Table 3-30. Wideband Frequency Accuracy Test RecordFrequency Measured Tolerance Limits Measured Flatness Error Measured ErrorTable 3-31. Wideband Accuracy at 1 kHz Test Record 5790A 1-Year Spec ± ppm Table 3-32. Wideband Flatness Test Record cont 1 kHz Absolute Error ppm Table 3-33. Wideband Absolute Error 10 Hz to 500 kHzFlatness Error ppm Error Sum ppm Kelvin-Varley Setting Div. SettingTable 3-34. Load Regulation Test Record 5700A/5720A Series Range Table 3-37. AC V Distortion Test Summary UUT Error Display Reading5700A/5720A Series II Output Load Resistors A Message From static awarenessFluke Corporation 5. USE STATIC SHIELDING CONTAINERS FOR HANDLING AND TRANSPORT Title Maintenance 5700A/5720A Series II Calibrator 4-1. Introduction 4-2. Cleaning the Air Filter 4-4. Cleaning PCA’s 4-3. General Cleaning4-5. Access Procedures 4-9. Rear Panel Removal and Installation 4-10. Rear Panel Assembly Access 4-12. Display Assembly Removal and Installation 4-11. Front Panel Removal and Installation 4-14. Analog Assembly Removal and Installation 4-13. Keyboard Assembly Removal and Installation FRONT PANEL Figure 4-5. Analog and Digital Assemblies 4-15. Digital Assembly Removal and Installation 4-18. Front/Rear Binding Post Reconfiguration4-16. Power Transformer Removal and Installation 4-17. Hybrid Cover Removal 6. Install the Front Panel 4-19. Installing a Wideband AC Module Option 4-21. Replacing the Clock/Calendar Backup Battery4-20. Clearing Ghost Images from the Control Display 4-23. Using the ETIME Command 4-22. Using Remote Commands Reserved for ServicingUsing The Fatality? and Fatalclr Commands ETIME FATALITY? FATLCLR?Response 5700A/5720A Series II Calibrator Troubleshooting 5700A/5720A Series II Calibrator 2701 A7 8255 Port a Fault 5-2. Interpreting Diagnostic Fault Codes2702 A7 8255 Port B Fault 2703 A7 8255 Port C Fault 2706 A7 Current Compliance Fault 2705 A7 Oven Regulation Fault2707 A7 Hardware Initialization Fault 2709 A7 Current Magnitude Fault 2719 A7 8255 Was Reset 2718 Fault In Setting Up AC For Diagnostics2713 A7 Hi-Res Loop In 100Hz Range 2714 A7 Hi-res Loop In 1kHz Range 2802 A11 8255 Port B Data Bus 2801 A11 8255 Port a Wires2803 A11 8254 Status Words 2804 A11 DAC Heaters Not Regulated 2809 A11 DAC Monitoring Fault 2808 A11 ADC Amp Gain Error2810 A11 +11V DC Range Fault 2811 A11 -11V DC Range Fault 2816 A11 13V Buffered Reference Fault 2815 A11 6.5V Reference Fault2817 A11 13V Reference Fault 2818 Assembly A11 Missing 2826 A11 A/D Overload Fault 2822 A8/A11 -11/22V DC Zero Estimate Fault3101 A14 8255 Port a Fault 3102 A14 8255 Port B Fault 3104 A15 HV Oven Regulation Fault 3103 A14 8255 Port C Fault3105 A15 HV I Oven Regulation Fault 3106 A15 DC HV Amp Noise Fault 3110 A15 HV +DC Series Pass & Current Fault 3109 A15 HV +DC Preamplifier Fault3111 A15 HV +DC High Voltage Output Fault 3112 A15 HV +DC Ref/error Amplitude Fault 3117 A14/A15 HV +DC Current Error Amp Fault 3116 A15 HV -DC Reference/error Amp Fault3118 A14/A15 HV -DC Current Error Amp Fault 3119 A14/A15 HV +DC Current Abs. Value 3122 A14/A15 HV AC 1kHz, Preamp Lo 3126 A14/A15 HV AC 100Hz, Preamp Fault3123 A14/A15 HV AC 1kHz, Preamp Mid 3124 A14/A15 HV AC 1kHz, Preamp Hi 3129 A14/A15 HV AC 1kHz, Output Mid 3128 A14/A15 HV AC 1kHz, Output Lo3130 A14/A15 HV AC 1kHz, Output Hi 3131 A14/A15 HV AC 100Hz, Output Lo 3136 A14 8255 Was Reset 3135 Assembly A14 Not Responding3137 A14/A15/A16 2.2A AC Range Mag. Fault 3134 Spare 3302 A9 8255 Port B Fault 3301 A9 8255 Port a Fault3140 A14/A15/A16 2.2A AC Range Abs. Value 3141 A14/A15/A16 2.2A DC Range Dummy Load 3304 A9 10V Source Fault 3303 A9 8255 Port C Fault3305 A9 5V Source Fault 3306 A9 2V Source Fault 3310 A9 Diff Amp Noise Fault 3309 A9 Diff Amp Gain Fault3311 A9/A10 Ohms 101 Divider Fault 3312 A9/A10 Ohms 11 Divider Fault 3316 A9/A10 19 Ohm Cal Diag Fault 3315 A9/A10 10 Ohm Cal Diag Fault3317 A9/A10 100 Kilohm Ratio Fault 3318 A9/A10 190 Kilohm Ratio Fault 3324 A9/A10 100M Ohm Ratio Fault 3321 A9/A10 10M Ohm Ratio Fault3325 A9/A10 10 Kilohm Check Fault 3326 A9/A10 19 Kilohm Check Fault 3328 A9/A10 1.9 Kilohm Check Fault 3327 A9/A10 1 Kilohm Check Fault3329 A9/A10 100 Ohm Check Fault 3330 A9/A10 190 Ohm Check Fault 3335 A9/A10 Ohms Short Check Fault 3334 A9/A10 1.9 Ohm Check Fault3336 A9/A10 2 Wire Compensation Fault 3337 A9/A10 Ohms Correction Factor Fault 3400 A12 8255 Control Word 3341 A9/A10 190 Ohm Cal Diag Fault3401 A12 8255 Port A 3402 A12 8255 Port B 3409 A13 Phase Lock Loop Fault 3408 A13 Fixed Ampl. Osc Fault3410 A12/A13 22V Amp Bias Adj Error 3412 A12 To A13 Interface Fault 3417 A12 DC Sensor Buffer Fault 3416 A12/A13 DAC 15th Bit Fault3418 A12 Sensor Loop/SQ. Root Amp Fault 3414 A12/A13 Nonlinear Control Loop 2vrng 3424 Assembly A13 Missing 3423 Assembly A12 Missing3425 Assembly A12 Or A13 Not Responding 3426 A12 8255 Was Reset 3510 A16 220V Amp Fault 3508 A16/A14 220V AC Range Output Fault3503 A16 8255 Port C 3504 Spare 3511 A16 Incorrect PA Input 3520 A16 PA Oven Regulation Fault3512 Spare 3513 Spare 3524 A16 Power Amp Is Too Hot 3521 Assembly A16 Is Not Responding3525 220V DC Initialization Fault 3526 220V AC Initialization Fault 3600 +17S Supply Fault 3530 A16 8255 Was Reset3601 -17S Supply Fault 3602 +15S Supply Fault 3606 LH Com Ground Fault 3605 -42S Supply Fault3607 -5lH Supply Fault 3608 +5rLH Supply Fault 3612 +15 OSC Supply Fault 3611 -PA Supply Fault3613 -15 OSC Supply Fault 3614 OSC Com Ground Fault 3701 A21 8255 Port A Fault 3615 S Com Ground Fault3702 A21 8255 Port B Fault 3703 A21 8255 Port C Fault 3802 A8 8255 Port B Fault 3801 A8 8255 Port A Fault3803 A8 8255 Port C Fault 3804 A8 Zero Amp Lo Noise Fault 3810 A8 2.2V Amp Noise Fault 3811 A8 Zero Amp Offset 3809 A8 Zero Amp Hi Gain Fault3812 A8 2.2V Gain Fault 3813 A8 220mV Offset Fault 3814 A8 220mV Divider Fault 3815 A8 22mV Divider Fault 3816 Spare 3825 Assembly A8 Not Responding 3824 A8 Oven Regulation Fault3826 A8 8255 Was Reset 3827 Assembly A8 Too Hot 3900 A5 8255 Control Word 3906 A6 Phase Lock Loop At 30MHz 3905 A6 Phase Lock Loop At 10MHz3907 A5 Rms Sensor At 10MHz 3908 A5 Rms Sensor At 30MHz 3915 A5 10DB Output Attenuation Fault 3914 A5 0DB Output Attenuation Fault3911 A5/A6 Ampl. Control At 30MHz 3912 A5/A6 Output Offset At 10MHz 3917 A5 30DB Output Attenuation Fault 3916 A5 20DB Output Attenuation Fault3918 A5 40DB Output Attenuation Fault 3922 A5/A6 Wideband Initialization Fault 5-3. Component-level Troubleshooting 3923 A5 8255 Was Reset5-4. Troubleshooting the Wideband Output Assembly A5 Component-level Troubleshooting All measurements are referenced to SCOM TP16 or TP17 and all 5-5. Troubleshooting the Wideband Oscillator Assembly A6 F5-2.EPS Figure 5-2. Waveform at TP1 F5-3.EPS Figure 5-3. Waveform at TP15 F5-4.EPS Figure 5-4. Waveform at Pins 14 and 15 of U1 F5-5.EPS 10 ms 5-7. Current Section 5-6. Troubleshooting the Current/Hi-Res Assembly A7 F5-6.EPS Figure 5-6. Waveform at Pin 11 of K2 1.2 Ω Figure 5-7. Waveform at Pin 6 of K2K5C, K5D K10, K13 F5-10.EPS F5-9.EPS F5-11.EPS All measurements are referenced to LHCOM TP18 5-8. Hi-Res Oscillator Section F5-13.EPS Figure 5-13. Waveform at TP12 5-9. Troubleshooting the Switch Matrix Assembly A8 F5-15.EPS Figure 5-15. Waveform at TP16 5-11. Two-wire Compensation Circuit 5-10. Troubleshooting the Ohms Cal Assembly A9 5-12. Troubleshooting the Ohms Main Assembly A10 5-13. Troubleshooting the DAC Assembly A11 Figure 5-18. Waveform at TP4, Calibrator Set to Figure 5-17. Waveform at TP6F5-17.EPS F5-18.EPS F5-19.EPS Figure 5-19. Waveform at TP4, Calibrator Set to F5-20.EPS Figure 5-20. Waveform at TP7 F5-21.EPS Figure 5-21. Waveform at TP5 5-14. Duty-cycle Control Circuit F5-22.EPS Figure 5-22. Waveform at Pin 10 of U6 Figure 5-24. Waveform at Pin 4 of U10 Figure 5-23. Waveform at Pin 6 of U13F5-23.EPS F5-24.EPS U11, Q30, Q31, Q32, and their associated components 5-15. ADC Circuit 5-16. Buffered Reference SIP Assembly A11A2 5-17. Troubleshooting the Oscillator Control Assembly A12 Figure 5-28. Waveform at Pin 6 of U11 Figure 5-27. Waveform at Anode of CR4F5-27.EPS F5-28.EPS F5-29.EPS Figure 5-29. DC Sense Buffer Waveform TP6 5-18. Troubleshooting the Oscillator Output Assembly A13 ∙ TP5 positive voltage ∙ TP4 negative voltage ∙ TP3 positive voltage 5-19. Troubleshooting the High Voltage Control Assembly A14 F5-31.EPS Figure 5-31. Waveform at TP3 5-20. Magnitude Control Circuit 5-21. Troubleshooting the High Voltage/High Current Assembly A15 operation refer to Figure 2-25 in the Theory of Operation section. During normal operation in the 1100V ac mode, internal software monitors the output and makes corrections or trips the instrument into standby. This internal monitoring can cause difficulty when troubleshooting a faulty High Voltage assembly. If during the next step 8 the instrument keeps tripping into standby, defeat the monitoring by connecting a jumper from TP9 to TP10 on the DAC assembly Figure 5-32. Waveform at Pin 18 of Hybrid H4 5-22. Troubleshooting the Power Amplifier Assembly A16 Figure 5-33. Power Amplifier with Calibrator Set to 22V at 1 kHz Remove any jumpers left in place from step 8 before continuing AC elsewhere in the Calibrator 5-23. Troubleshooting the Filter/PA Supply Assembly A18 J201. The +PA supply at +180Vshould go into current limit. The oscilloscope should show a repeating pattern in which the +PA supply climbs to about +180V then drops to 0V. If a failure is detected, check Q203, VR246, VR213, U201C, and associated components 5700A/5720A Series II Calibrator List of Replaceable Parts 5700A/5720A Series II Calibrator A * symbol indicates a device that may be damaged by static discharge 6-2. How to Obtain Parts6-1. Introduction 6-3. Manual Status Information Manual Status Information Assembly Name 6-5. Service CentersRef or Option No Fluke Table 6-1. Front Panel Final Assembly Service CentersReference Description Designator Fluke Stock No Figure 6-1. Front Panel Final Assembly 5700A-T&Bf6-1.eps Table 6-1. Chassis Final Assembly 5700A T&B Figure 6-2. Chassis Final Assembly1 of f61a1.eps f61a2.eps Figure 6-2. Chassis Final Assembly cont Table 6-1. Rear Panel Final Assembly f61b.eps Figure 6-3. Rear Panel Final Assembly Table 6-2. A1 Keyboard PCA ISOLATOR,OPTO,OPTICAL SWITCH,INFRAREDCR1-4 DT1, DT2 W1 LED,GREEN,SUBMINIATURE Figure 6-4. A1 Keyboard PCA 5700A-1603 Designator Table 6-3. A2 Front Panel PCA Table 6-3. A2 Front Panel PCA cont 5700A-1602 Figure 6-5. A2 Front Panel PCA57001602.EPS Table 6-4. A3 Analog Motherboard PCA Figure 6-6. A3 Analog Motherboard PCA 5700A-1601 Table 6-5. A4 Digital Motherboard PCA 5700A-1605 Figure 6-7. A4 Digital Motherboard PCA57001605.EPS Table 6-6. A5 Wideband Output PCA, Option Table 6-6. A5 Wideband Output PCA, Option -03 cont R69,R70 R72,R73,R80-83 R74 R75 R78,R79,R86-89 R92-95 R96-99 R100 R101 5700A-1611 Figure 6-8. A5 Wideband Output PCA, Option57001611.EPS Table 6-7. A6 Wideband Ocillator PCA, Option Table 6-7. A6 Wideband Ocillator PCA, Option -03 cont CONNECTOR ,CONN,DIN41612,TYPE C,RT ANG,64 PIN R58,R112,R212 R312,R412,R512 R59 R61 R62,R64,R65,R69 R63 R68 R71 5700A-1610 Figure 6-9. A6 Wideband Oscillator PCA, Option57001610.EPS Table 6-8. A7 Current/High-Res Oscillator PCA Table 6-8. A7 Current/High-Res Oscillator PCA cont List of Replaceable Parts 5700A-1621 Figure 6-10. A7 Current/HIgh-Res Oscillator PCA57001621.EPS Reference Designator Table 6-9. A8 Switch Matrix PCA Table 6-9. A8 Switch Matrix PCA cont Figure 6-11. A8 Switch Matrix PCA 5700A-162257001622.EPS Table 6-10. A9 Ohms Cal PCA Table 6-10. A9 Ohms Cal PCA cont 5700A-1631 Figure 6-12. A9 Ohms Cal PCA57001631.EPS Table 6-11. A10 Ohms Main PCA 5700A-1630 Figure 6-13. A10 Ohms Main PCA57001630.EPS C110,C111 CR1,CR3-6,CR8, CR12,CR13 CR2 Table 6-12. A11 DAC PCA Table 6-12. A11 DAC PCA cont Service Centers VR13 VR18,VR22 VR25 VR26 VR27 VR28 VR29 VR33,VR34 X1 Z2 Z4 Z5 Z8 Z10 5700A-1640 Figure 6-14. A11 DAC PCA57001640.EPS Table 6-13. A11A1 DAC Filter SIP PCA Figure 6-15. A11A1 DAC Filter SIP PCA 5700A-1643 Table 6-14. A11A2 DAC Buffered Reference SIP PCA Figure 6-16. A11A2 DAC Buffered Reference SIP PCA 5700A-1644 Table 6-15. A12 Oscillator Control PCA Stock Table 6-15. A12 Oscillator Control PCA cont 5700A/5720A Series II Calibrator 5700A-1650 Figure 6-17. A12 Oscillator Control PCA57001650.EPS Table 6-16. A13 Oscillator Output PCA Table 6-16. A13 Oscillator Output PCA cont Table 6-16. A13 Oscillator Output PCA cont 5700A-1651 Figure 6-18. A13 Oscillator Output PCA57001651.EPS Table 6-17. A13A1 Oscillator Wideband SMD PCA Figure 6-19. A13A1 Oscillator Wideband SMD PCA 5700A-1652 Table 6-18. A14 High Voltage Control PCA Table 6-18. A14 High Voltage Control PCA cont 5700A-1661 Figure 6-20. A14 High Voltage Control PCA57001661.EPS Table 6-19. A15 High Voltage/High Current PCA Table 6-19. A15 High Voltage/High Current PCA cont 5700A-1660 Figure 6-21. A15 High Voltage/High Current PCA57001660.EPS CR20,CR21,CR23 Table 6-20. A16 Power Amplifier PCA R9,R10,R16,R33, R40,R50 R59, R115,R148 R149 R11,R12 Table 6-20. A16 Power Amplifier PCA cont 5700A/5720A Series II Calibrator Figure 6-22. A16 Power Amplifier PCA 5700A-767057001670.EPS Table 6-21. A16A1 Power Amplifier Digital Control SIP PCA 5700A-1671 Figure 6-23. A16A1 Power Amplifier Digital Control SIP PCA Table 6-22. A17 Regulator/Guard Crossing PCA Table 6-22. A17 Regulator/Guard Crossing PCA cont 5700A-1680 Figure 6-24. A17 Regulator/Guard Crossing PCA57001680.EPS CR1,CR2,CR04, CR5 CR8,CR10, CR12,CR13 Table 6-23. A18 Filter/PA Supply PCA Table 6-23. A18 Filter/PA Supply PCA cont VR211,VR217 VR227,VR231 VR212,VR216 VR226,VR232 VR214,VR230 5700A-7690 Figure 6-25. A18 Filter/PA Supply PCA57001690.EPS C24,C25 CR1-4,CR9-12 CR8,CR16, CR21- 24,CR29-34 Table 6-24. A19 Digital Power Supply PCA Table 6-24. A19 Digital Power Supply PCA cont Figure 6-26. A19 Digital Power Supply PCA 5700A-160457001604.EPS Table 6-25. A20 CPU PCA Ref DesPart Number Table 6-26. A20 CPU PCA cont 57001606.EPS Figure 6-27. A20 CPU PCA Table 6-27. A21 Rear Panel PCA Table 6-27. A21 Rear Panel PCA cont 5700A-1609 Figure 6-28. A21 Rear Panel PCA57001609.EPS 5700A/5720A Series II Calibrator Schematic Diagrams 5700A/5720A Series II Calibrator Figure 7-1. A1 Keyboard PCA Schematic Diagrams Figure 7-1. A1 Keyboard PCA cont 5700A/5720A Series Figure 7-2. A2 Front Panel PCA Figure 7-2. A2 Front Panel PCA cont Figure 7-2. A2 Front Panel PCA cont Schematic Diagrams Service Manual 5700A/5720A SeriesFigure 7-2. A2 Front Panel PCA cont Figure 7-2. A2 Front Panel PCA cont Figure 7-3. A3 Analog Motherboard PCA Figure 7-23. A3 Analog Motherboard PCA cont Figure 7-3. A3 Analog Motherboard PCA cont Figure 7-3. A3 Analog Motherboard PCA cont Schematic Diagrams Service Manual Figure 7-4. A4 Digital Motherboard PCA Figure 7-4. A4 Digital Motherboard PCA cont ahp46f.tif Service Manual Figure 7-5. A5 Wideband Output PCA Option 5700A-1611 Figure 7-5. A5 Wideband Output PCA Option -03 cont Figure 7-5. A5 Wideband Output PCA Option -03 cont Schematic Diagrams Service Manual 7-23 5700A-7610Figure 7-6. A6 Wideband Oscillator PCA Option Figure 7-6. A6 Wideband Output PCA Option Figure 7-6. A6 Wideband Oscillator PCA Option -03 cont Service Manual 5700A-1621 Figure 7-7. A7 Current/High-Resolution Oscillator PCA Figure 7-7. A7 Current/High-Resolution Oscillator PCA cont Figure 7-7. A7 Current/High-Resolution Oscillator PCA cont Schematic Diagrams Service Manual 7-31 Figure 7-7. A7 Current/High-Resolution5700A-1021 4 of Oscillator PCA cont 5700A-1622 Figure 7-8. A8 Switch Matrix PCA Figure 7-8. A8 Swith Matrix PCA cont Figure 7-8. A8 Switch Matrix PCA cont Figure 7-8. A8 Swith Matrix PCA cont Schematic Diagrams Service Manual Figure 7-8. A8 Switch Matrix PCA cont5700A/5720A Series Figure 7-8. A8 Swith Matrix PCA cont 5700A-1631 Figure 7-9. A9 Ohms Cal PCA Figure 7-9. A9 Ohms Cal PCA cont Service Manual 5700A/5720A SeriesFigure 7-9. A9 Ohms Cal PCA cont Figure 7-9. A9 Ohms Cal PCA cont Schematic Diagrams Service Manual Figure 7-10. A10 Ohms Main PCA Figure 7-10. A10 Ohms Main PCA cont Figure 7-10. A10 Ohms Main PCA Schematic Diagrams Service Manual 5700A/5720A SeriesFigure 7-10. A10 Ohms Main PCA cont Figure 7-10. A10 Ohms Main PCA 5700A-7640 Figure 7-11. A11 DAC PCA Figure 7-11. A11 DAC PCA cont R128 22uFC112 200K Figure 7-11. A11 DAC PCA cont 7-52 Figure 7-11. A11 DAC PCA cont Schematic Diagrams Service Manual Figure 7-12. A11A1 DAC Filter SIP PCA Figure 7-13. A1142 DAC Buffered Reference SIP PCA Figure 7-14. A12 Oscillator Control PCA cont 5700A-7650 3. ALL GND CONNECTIONS DENOTED WITH 4. C5 AND C55 ARE NOT INSTALLEDA 1 ARE BUSSED AND CONNECTED TO GND3 AT ONE POINT DG211 Figure 7-14. A12 Oscillator Control PCA cont 7-60 Figure 7-15. A13 Oscillator Output PCA Figure 7-15. A13 Oscillator Output PCA cont Figure 7-15. A13 Oscillator Output PCA cont Schematic Diagrams Service Manual Figure 7-16. A13A1 Oscillator Wideband SMD PCA Figure 7-16. A13A1 Oscillator Wideband SMD PCA cont Figure 7-17. A14 High Voltage Control PCA Figure 7-17. A14 High Voltage Control PCA cont 7-68 Figure 7-17. A14 High Voltage Control PCA cont Service Manual 5700A/5720A SeriesFigure 7-17. A14 High Voltage Control PCA cont Figure 7-17. A14 High Voltage Control PCA cont 5700A-1660 Figure 7-18. A15 High Voltage/ High Current PCA Figure 7-18. A15 High Voltage/High Current PCA cont Service Manual 5700A-7670 Figure 7-19. A16 Power Amplifier PCA 4. NOT INSTALLED Figure 7-19. A16 Power Amplifier PCA cont 10 M 2N4044 7-78 Figure 7-19. A16 Power Amplifier PCA cont Figure 7-20. A16A1 Power Amplifier Digitial Control SIP PCA Figure 7-20. A161A1 Power Amplifier Digital 7-80Control SIP PCA cont Figure 7-21. A17 Regulator/Guard Crossing PCA 5700A-1680 Figure 7-21. A17 Regulator/Guard Crossing PCA cont Figure 7-21. A17 Regulator/Guard Crossing PCA cont 7-84 5700A-7690Figure 7-22. A18 Filter/PA Supply PCA Figure 7-22. A18 Filter/PA Supply PCA cont Service Manual Figure 7-23. A19 Digital Power Supply PCA Figure 7-23. A19 Digital Power Supply PCA cont Figure 7-24. A20 CPU PCA Figure 7-24. A20 CPU PCA cont Figure 7-24. A20 CPU PCA cont Schematic Diagrams Service Manual 5700A/5720A SeriesFigure 7-24. A20 CPU PCA cont Figure 7-24. A20 CPU PCA cont Schematic Diagrams Service Manual Figure 7-25. A21 Real Panel PCA Figure 7-25. A21 Rear Panel PCA cont Figure 7-25. A21 Rear Panel PCA cont Schematic Diagrams Service Manual 5700A/5720A SeriesFigure 7-25. A21 Rear Panel PCA cont Figure 7-25. A21 Rear Panel PCA cont Schematic Diagrams Service Manual Figure 7-26. Hybrids Figure 7-26. Hybrids cont Figure 7-26. Hybrids cont Schematic Diagrams Service Manual 5700A/5720A SeriesFigure 7-26. Hybrids cont Figure 7-26. Hybrids cont Schematic Diagrams 5700A/5720A Series Service Manual