Fluke 5720A - Manual

5700A/5720A Series II Service Manual ii 1-34. General Specifications.......................................................................... 1-36 1-35. Auxiliary Amplifier Specifications ...................................................... 1-37 2 Theory of Operation.................................

Contents (continued) iii 2-49. Decoding and Timing Circuitry ................................................... 2-28 2-50. Control Display Circuitry ............................................................ 2-29 2-51. Output Display Circuitry ........................................................

5700A/5720A Series II Service Manual iv 2-113. ADC Amplifier ............................................................................ 2-69 2-114. ADC Input Selection.................................................................... 2-69 2-115. ADC Circuit .........................................

Contents (continued) v 2-169. Ohms Main Assembly (A10) ........................................................... 2-109 2-170. Selection of Resistance Values.................................................... 2-109 2-171. Ohms Main Assembly Support of Current Function Calibration 2-112 2-172. Ohms...

5700A/5720A Series II Service Manual vi 3-27. Wideband AC Voltage Module Output Verification ....................... 3-38 3-28. Wideband Output Accuracy at 1 kHz Test........................................... 3-39 3-29. Wideband Output Flatness Test ....................................................

Contents (continued) vii 5-13. Troubleshooting the DAC Assembly (A11) .................................... 5-58 5-14. Duty-cycle Control Circuit .......................................................... 5-63 5-15. ADC Circuit ............................................................................

ix List of Tables Table Title Page 1-1. Auxiliary Amplifier Data....................................................................................... 1-6 1-2. 5720A Series II DC Voltage Specifications: 99 % and 95 % Confidence Levels 1-14 1-3. 5700A Series II DC Voltage Specifications: 99 % and 95...

Contents (continued) xi 3-38. Test Record for Flatness Check of the AC 2 mV Range ....................................... 3-705-1. Verifying Multiplexer U 6 ..................................................................................... 5-465-2. Ohms Main Resistance Tolerance ....................

xiii List of Figures Figure Title Page 1-1. Time and Costs: Calibrator Calibration................................................................. 1-10 1-2. Volt-Hertz Capability ............................................................................................ 1-22 2-1. Digital Section B...

5700A/5720A Series II Service Manual xiv 2-31. Ohms Main Assembly Simplified Schematic........................................................ 2-1112-32. Two-Wire Lead Drop Compensatin Circuit .......................................................... 2-1142-33. Calibration to an External 10 k Ω Sta...

Contents (continued) xv 5-18. Waveform at TP4, Calibrator Set to 0V ................................................................ 5-595-19. Waveform at TP4, Calibrator Set to 6.5V ............................................................. 5-605-20. Waveform at TP7.................................

1-1 Chapter 1 Introduction and Specifications Title Page 1-1. Introduction .......................................................................................... 1-3 1-2. Contacting Fluke .................................................................................. 1-4 1-3. About this Manua...

Introduction and Specifications Introduction 1 1-3 1-1. Introduction The Fluke Model 5700A/5720A Series II calibrators are precise instruments thatcalibrate a wide variety of electrical measuring instruments. These calibrators maintainhigh accuracy over a wide ambient temperature range, allowing the...

5700A/5720A Series II CalibratorService Manual 1-4 • Extensive internal self testing and diagnostics of analog and digital functions. • A traceable calibration procedure for all modes and ranges that requires only 10V,1 Ω , and 10 k Ω external standards, with only occasional independent verification...

Introduction and Specifications Additional Instruction Manuals 1 1-5 • Using auxiliary amplifiers: Chapter 4 • Self calibration: Chapters 1 and 7 • Remote operation (IEEE-488 or serial): Chapter 5 • Options and accessories: Chapters 2 and 8 • Instrument specifications: The end of this Chapter • Theo...

5700A/5720A Series II CalibratorService Manual 1-6 1-7. Auxiliary Amplifiers The Fluke Model 5725A Amplifier is available to extend the high voltage performanceand current range of the calibrator: Interface connectors on the calibrator’s rear panel accept cables to directly operate a5725A. Three amp...

Introduction and Specifications Support Equipment and Services 1 1-7 ordering instructions for this support equipment and other Fluke instruments, refer to theFluke catalog, or contact a representative at a Fluke Sales and Service Center. 1-10. 732B Direct Voltage Reference Standard The Fluke 732B i...

5700A/5720A Series II CalibratorService Manual 1-10 COST $ COST $ CALIBRATION CYCLE CALIBRATION CYCLE TRADITIONAL CALIBRATOR CALIBRATION 5700A/5720A SERIES II CALIBRATION TIME TIME f1-1.eps Figure 1-1. Time and Costs: Calibrator Calibration 1-17. The Calibration Process Calibration requires only thr...

Introduction and Specifications Calibration Check 1 1-11 • Except for the internal ac/dc transfer standard, the internal check standards aredirectly calibrated by traceable external standards every time the 5700A/5720ASeries II is calibrated. • The internal ac/dc transfer standard is never adjusted,...

5700A/5720A Series II CalibratorService Manual 1-12 • The process is consistent and automatic: it does not require an operator’s assistance. Each calibration check produces a new set of data points for accumulating a historicalrecord. When this process is externally automated, significant history ca...

Introduction and Specifications Specifications 1 1-13 You do not need to add anything to absolute uncertainty to determine the ratios betweenthe calibrator’s uncertainties and the uncertainties of your calibration workload. Relative uncertainty specifications are provided for enhanced accuracy appli...

Introduction and Specifications DC Voltage Specifications 1 1-15 Table 1-3. 5700A Series II DC Voltage Specifications: 99 % and 95 % Confidence Levels 5700A 99% 99 % Confidence Level Range Resolution Absolute Uncertainty ± 5 °C from calibration temperature For fields strengths >1 V/m but ≤ 3 V/m,...

5700A/5720A Series II CalibratorService Manual 1-16 Table 1-4. DC Voltage Secondary Performance Specifications and Operating Characteristics Temperature Coefficient Adder [Note 2] Noise Range Stability [Note 1] ± 1 °C 10 °-40 °C 0 °-10 °C and Linearity ± 1 °C Bandwidth 0.1-10 Hz Bandwidth 10 Hz-10 k...

Introduction and Specifications AC Voltage Specifications 1 1-17 1-29. AC Voltage Specifications Table 1-5. 5720A Series II AC Voltage Specifications: 99 % Confidence Level 5720A 99% 99 % Confidence Level Range Resolution Frequency Absolute Uncertainty ± 5 °C from calibration temperature Relative Un...

5700A/5720A Series II CalibratorService Manual 1-18 Table 1-6. 5720A Series II AC Voltage Specifications: 95 % Confidence Level 5720A 95% 95 % Confidence Level Range Resolution Frequency Absolute Uncertainty ± 5 °C from calibration temperature Relative Uncertainty ± 1 °C 24 Hours 90 Days 180 Days 1 ...

5700A/5720A Series II CalibratorService Manual 1-20 Table 1-8. 5700A Series II AC Voltage Specifications: 95 % Confidence Level 5700A 95% 95% Confidence Level Range Resolution Frequency Absolute Uncertainty ± 5 °C from calibration temperature Relative Uncertainty ± 1 °C 24 Hours 90 Days 180 Days 1 Y...

Introduction and Specifications Resistance Specifications 1 1-23 1-30. Resistance Specifications Table 1-10. 5720A Series II Resistance Specifications: 99 % and 95 % Confidence Levels 5720A 99% 99% Confidence Level Nominal Value Absolute Uncertainty of Characterized Value ± 5 °C from calibration tem...

Introduction and Specifications DC Current Specifications 1 1-27 1-31. DC Current Specifications Table 1-14. 5720A Series II DC Current Specifications: 99 % and 95 % Confidence Levels 5720A 99% 99 % Confidence Level Range Resolution Absolute Uncertainty ± 5 °C from calibration temperature. For field...

Introduction and Specifications AC Current Specifications 1 1-31 Table 1-18. 5720A Series II AC Current Specifications: 95 % Confidence Level 5720A 95% 95 % Confidence Level Range Resolution Frequency Absolute Uncertainty ± 5 °C from calibration temperature For fields strengths >0.4 V/m but ≤ 3 V...

Introduction and Specifications Wideband AC Voltage (Option 5700-03) Specifications 1 1-35 1-33. Wideband AC Voltage (Option 5700-03) Specifications Table 1-22. Wideband AC Voltage (Option 5700-03) Specifications Specifications apply to the end of the cable and 50 Ω termination used for calibration ...

5700A/5720A Series II CalibratorService Manual 1-36 1-34. General Specifications Warm-Up Time: Twice the time since last warmed up, to a maximum of 30 minutes. System installation: Rear output configuration and rack- mount kit available. Standard interfaces: IEEE-488, RS-232, 5725A, 5205A or 5215A, ...

Introduction and Specifications Auxiliary Amplifier Specifications 1 1-37 1-35. Auxiliary Amplifier Specifications For complete specifications, see the 5205A and 5220A Operators Manuals. 5205A (220V - 1100 V ac, 0 V - 1100 V dc) Overshoot: < 10 % Distortion (bandwidth 10 Hz - 1 MHz): 10 Hz - 20 k...

2-1 Chapter 2 Theory of Operation Title Page 2-1. Introduction .......................................................................................... 2-5 2-2. Calibrator Overview ............................................................................. 2-5 2-3. Internal References .............

5700A/5720A Series II Calibrator Service Manual 2-4 2-155. High Voltage Assemblies (A14 and A15) ....................................... 2-96 2-156. 1100V AC Range ......................................................................... 2-96 2-157. 1100V DC Range ......................................

Theory of Operation Introduction 2 2-5 2-1. Introduction This section provides theory of operation in increasing level of detail. The calibrator isfirst broadly defined in terms of digital functions (relating to the Digital Motherboardassembly) and analog functions (relating to the Analog Motherboar...

5700A/5720A Series II Calibrator Service Manual 2-6 After initial functional verification of the Fluke Thermal Sensors, their characteristicsonly change by less than 1/10th of the allowed ac/dc error per year. External calibrationof the ac voltage function of the Calibrator consists of verifying tha...

Theory of Operation Analog Section Overview 2 2-7 ahp003f.eps Figure 2-1. Digital Section Block Diagram

5700A/5720A Series II Calibrator Service Manual 2-8 These analog assemblies are interfaced to the Analog Motherboard assembly (A3). Theguarded digital bus generated by the guard crossing portion of the Regulator/GuardCrossing assembly controls all analog assemblies except the Filter/PA Supply. TheGu...

Theory of Operation Functional Description Presented by Output Function 2 2-11 The 1100V range is generated by the High Voltage/High Current assembly (A15)operating in conjunction with the Power Amplifier assembly and the High VoltageControl assembly. The 11V range of the DAC assembly is routed to t...

5700A/5720A Series II Calibrator Service Manual 2-12 2-12. Wideband AC V Functional Description (Option -03) The Wideband AC Voltage module (Option -03) consists of the Wideband Oscillatorassembly (A6) and the Wideband Output assembly (A5). There are two widebandfrequency ranges: • 10 Hz to 1.1 MHz ...

Theory of Operation System Interconnect Detailed Circuit Description 2 2-13 2-15. Ohms Functional Description Two assemblies function as one to supply the fixed values of resistance: • Ohms Main assembly (A10) • Ohms Cal assembly (A9) All of the resistance values except the 1 Ω , 1.9 Ω , and short a...

2 Theory of Operation a h p 3 5 f . e p s 2-15 Functional Description Presented by 0utput Function Figure 2-4. System Interconnections

Theory of Operation System Interconnect Detailed Circuit Description 2 2-17 Table 2-1. Analog Motherboard Connectors Motherboard Connector Connected to Assembly J101 Wideband Oscillator Assembly (A6) J111 Wideband Output Assembly (A5) J201 and J202 Switch Matrix Assembly (A8) J211 and J212 Current/H...

5700A/5720A Series II Calibrator Service Manual 2-18 2-20. Front/Rear Binding Posts An internal cable can be configured to enable either the front panel or panel bindingposts. When compared to front panel binding posts, the rear panel provides the sameOUTPUT HI, OUTPUT LO, SENSE HI, SENSE LO, AND V ...

Theory of Operation Digital Section Detailed Circuit Description 2 2-19 Table 2-2. Supplies Generated by the Digital Power Supply Signal Name Test Point Nominal Output Tolerance Current Limit Rated Output +75V OUT TP2 73V +/-8% 121 mA 100 mA +35V OUT TP5 35V +/-7% 52 mA 40 mA +12 VOLTS TP8 12V +/-5%...

Theory of Operation Digital Section Detailed Circuit Description 2 2-21 2-30. CPU (Central Processing Unit) Assembly (A20) The CPU (Central Processing Unit) for the Calibrator is a single-board computer basedon a 68HC000 microprocessor. The CPU assembly communicates with the GuardedDigital section, ...

Theory of Operation Digital Section Detailed Circuit Description 2 2-23 Table 2-3. CPU Acronym Glossary Signal Name Function A01-A23 Address lines ADCLKCS* Clock/calendar (U33) chip select AS* Address strobe BERR* Bus error BGACK* Bus grant acknowledge BR* Bus request BRPDRTINT* Rear panel DUART int...

5700A/5720A Series II Calibrator Service Manual 2-24 2-33. Watchdog Timer The watchdog timer circuitry uses a 74HC4020 binary counter (U11) to divide the 450Hz from the clock generation circuit to produce interrupt DOGINTH, signifying that thesystem may be locked up. This interrupt is generated 1.14...

Theory of Operation Digital Section Detailed Circuit Description 2 2-25 2-35. Interrupt Controller PLD U10 is the priority interrupt controller. The interrupt controller reads incominginterrupts and interrupt control lines, then encodes the highest priority interrupt into theinterrupt level for the ...

Theory of Operation Digital Section Detailed Circuit Description 2 2-27 2-42. Clock Filter Circuit The clock filter circuit generates a 3.6864 MHz 200 mV sine wave for the Rear Paneland Front Panel assemblies. This circuit buffers the 3.6864 MHz Clock with an inverterin U3. The circuit contains dc-b...

Theory of Operation Digital Section Detailed Circuit Description 2 2-29 Table 2-6. Front Panel Memory Map Name Read/Write Address OTDCS* R/W D02000 to D027FF DMDCS* R/W D02800 to D02FFF ENCODERCS* R D03000 to D033FF ENCODERRESET* W D03000 to D033FF LED_OUTPUT_CNTRL R D03400 to D037FF LED_LATCH_EN W ...

5700A/5720A Series II Calibrator Service Manual 2-32 interrupt by reading U24. On a read, indicated by a logic low on ENCODERCS*, U24places the contents of a seven-bit up/down counter on the data bus. The counter keepstrack of the number of 180º rotations that have occurred between the time the inte...

Theory of Operation Analog Section Detailed Circuit Description 2 2-33 2-56. Analog Section Detailed Circuit Description Detailed descriptions of each assembly in the analog section are provided here.Simplified schematics are provided to supplement the text. 2-57. Filter/PA Supply (A18), Low-voltage...

5700A/5720A Series II Calibrator Service Manual 2-34 2-58. Unregulated OSC Supplies Line OSC COM is the return path for the +15 OSCR and -15 OSCR supplies. Thesesupplies use a full-wave center-tapped configuration. They consist of bridge rectifierCR3 and two filter capacitors, C4 and C6, for +15 OSC...

Theory of Operation Analog Section Detailed Circuit Description 2 2-35 2-64. FR2 Supplies FR2 COM is the return path for unregulated +30 FR2R supply and regulated -5 FR2supply. Each supply uses a full-wave, bridge configuration. The unregulated +30 FR2Rsupply consists of bridge rectifier CR7 and fil...

5700A/5720A Series II Calibrator Service Manual 2-36 ahp005f.eps Figure 2-6. Power Amplifier Output Supply Simplified Schematic

Theory of Operation Analog Section Detailed Circuit Description 2 2-37 2-67. ±250V and ±500V Supplies Input signals PA CT, PA HAC1, PA HAC2, PA LAC1, and PA LAC2 come from themain transformer. • PA CT is the center tap. • PA HAC1 and PA HAC2 are high voltage taps with approximately 400V rms andare f...

5700A/5720A Series II Calibrator Service Manual 2-40 The -44S supply uses the unregulated -44SR supply from the Filter assembly. Thissupply uses three-terminal TO-39 regulator U13, Q1, VR1, VR2, VR6, R17, R18, R19,PTC Resistor R61, CR22, CR23, CR32, CR33, C22, C25, C26, and C66. The regulatorIC, U13...

Theory of Operation Analog Section Detailed Circuit Description 2 2-41 supply. Capacitor C12 improves ripple rejection. Diodes CR9 and CR10 protect U5against input shorts, while CR12 protects against reverse voltage. 2-77. Guarded Digital Control Circuitry The Inguard CPU controls all the analog ass...

Theory of Operation Analog Section Detailed Circuit Description 2 2-43 2-85. Interface to Guarded Digital Bus The interface to the guarded digital bus consists of a 74HCT245 (U55), a 74HCT244(U52), two 74HC137s (U53 and U54), inverters U51B and U51D, resistor packs Z52,Z53, and Z54, and the POP line...

2 Theory of Operation 2-45 System Interconnection Detailed Circuit Description Figure 2-7. Switch Matrix Assembly Simplified Schematic a h p 3 7 f . e p s

5700A/5720A Series II Calibrator Service Manual 2-46 A UCN5801 driver (U13) drives non-latching relays on the motherboard. Themotherboard non-latching relay supply circuit, as outlined in sections A6 through A8 ofthe schematic diagram, contains U17, Q1, Q2, CR1, CR2, CR10, and R6-R12. Port A ofU1 pr...

Theory of Operation Analog Section Detailed Circuit Description 2 2-47 ahp006f.eps Figure 2-8. Switch Matrix Configuration for 11V DC and 22V DC Ranges

5700A/5720A Series II Calibrator Service Manual 2-48 2-90. Switch Matrix Operation : 2 . 2V AC and 22V AC Ranges Refer to Figure 2-9 for the following discussion. AC 2.2V and 22V ranges are generatedby the Oscillator assemblies and routed directly to the front panel binding posts throughrelays locat...

Theory of Operation Analog Section Detailed Circuit Description 2 2-49 ahp007f.eps Figure 2-9. Switch Matrix Configuration for 2.2V and 22V AC Ranges

5700A/5720A Series II Calibrator Service Manual 2-50 ahp008f.eps Figure 2-10. Switch Matrix Configuration for 220V DC and AC Ranges

Theory of Operation Analog Section Detailed Circuit Description 2 2-51 2-92. Switch Matrix Operation : 2 . 2V DC Range Refer to Figure 2-11 for the following discussion. The dc 2.2V range circuit consists ofthe dc 2.2V attenuator and a dc 2.2V range amplifier as outlined on sheet 3 of the SwitchMatr...

Theory of Operation Analog Section Detailed Circuit Description 2 2-53 2-93. Calibration of the 2 . 2V Range Refer to Figure 2-12 for the following discussion. Calibration of the 2.2V range involvesdetermining its offset and gain constants. To calibrate the offset: 1. The gain of the internal cal ze...

Theory of Operation Analog Section Detailed Circuit Description 2 2-55 ahp011f.eps Figure 2-13. Switch Matrix Configuration for 220 mV DC Range

5700A/5720A Series II Calibrator Service Manual 2-56 2-95. Switch Matrix Operation : 220 mV AC Range Refer to Figure 2-14 for the following discussion. As previously mentioned, the ac 220mV range uses the same resistor network as the dc 220 mV range. In generating the ac220 mV range the Oscillator a...

Theory of Operation Analog Section Detailed Circuit Description 2 2-63 ahp015f.eps Figure 2-17. DAC Assembly Simplified Schematic

5700A/5720A Series II Calibrator Service Manual 2-66 The 3V source is created from the 13V reference. The 13V reference is buffered by opamp U1B, configured as a voltage follower. The output from U1B is divided down to 3Vby a 100 k Ω and 30 k Ω resistor in the HR5 assembly, creating 3V. This 3V is a...

Theory of Operation Analog Section Detailed Circuit Description 2 2-67 In the 22V range, Q20 is off and Q21 is on, which switches in the 40 k Ω feedback resistors located on the HR6 assembly. Precise ratio matching of these resistors provideshigh accuracy in the 22V range. FET Q15 is on in the 22V r...

5700A/5720A Series II Calibrator Service Manual 2-68 2-109. Negative Offset Circuit This circuit creates a constant offset voltage of approximately -127 mV at the filterinput. Thus, for a DAC output voltage of 0V, the first channel count must beapproximately 400 to offset this negative voltage. This...

5700A/5720A Series II Calibrator Service Manual 2-70 2-115. ADC Circuit The adc (analog-to-digital converter) is shown on sheet 5 of the DAC schematic. Most of the adc is contained on one chip (U25) which uses the Fluke-patentedrecirculating remainder technique. The adc has rms noise of approximatel...

Theory of Operation Analog Section Detailed Circuit Description 2 2-71 ahp016f.eps Figure 2-18. ADC Circuit Measurement Functions

5700A/5720A Series II Calibrator Service Manual 2-72 During the remainder store function, U29 amplifies and stores the difference between theADC INPUT and the adc dac output on one of the remainder storage capacitors, C89 orC90. In this function, U29 is configured by the adc as a difference amplifie...

5700A/5720A Series II Calibrator Service Manual 2-74 All power supplies used by this assembly are generated by the Guard Crossing/Regulatorassembly (A17) except the +5 OSC supply, which is generated by a three-terminal +5Vregulator (U25) from the +15 OSC supply. The ±15 OSC supplies are buffered by ...

Theory of Operation Analog Section Detailed Circuit Description 2 2-75 2-123. Averaging Converter The averaging converter contains the buffer amplifier and rectifying amplifier circuits asoutlined on sheet 1 of the schematic. The buffer amplifier is a non-inverting unity gain amplifier (U3). Input t...

5700A/5720A Series II Calibrator Service Manual 2-76 ahp017f.eps Figure 2-19. Oscillator Control Analog Control Loop

Theory of Operation Analog Section Detailed Circuit Description 2 2-77 2-127. AC/DC Thermal Transfer Circuit Refer to Figure 2-20 for the following discussion. The ac/dc thermal transfer circuitachieves basic mid-band amplitude accuracy. This is done by first applying the referencevoltage (VREF) to ...

Theory of Operation Analog Section Detailed Circuit Description 2 2-81 ahp019f.eps Figure 2-21. Quadrature RC Oscillator Circuit

5700A/5720A Series II Calibrator Service Manual 2-82 2-131. Oscillator Output Digital Control The digital control circuit consists of an 82C55 Programmable Peripheral Interface(U26), a 5801 Latching Relay Driver (U24), and three HC374 Octal D-Type Flip Flops(U12, U32, U33). The Programmable Peripher...

Theory of Operation Analog Section Detailed Circuit Description 2 2-83 frequency and the sum of the phase shifts around the loop is zero for all frequencies, wehave satisfied one half of the requirement for oscillation. In summing the gain in dBaround the loop it is apparent that unity gain occurs a...

5700A/5720A Series II Calibrator Service Manual 2-84 that makes a positive to negative transition causes the phase detector to turn on either thepositive (CR5, CR6) or the negative (CR7, CR8) charge pump, depending on whichsignal is first. The Charge Pump is turned off when the other signal makes it...

Theory of Operation Analog Section Detailed Circuit Description 2 2-87 2-141. PA Common Circuitry Common circuitry consists of the +PA and -PA supplies, input stage, mid stage, and theoutput stage. These four circuits are described under the next four headings. Power Amplifier input node, gain, and ...

Theory of Operation Analog Section Detailed Circuit Description 2 2-89 2-146. PA Sense Current Cancellation Circuitry During dc operation of the Power Amplifier, sense current in the 500 k Ω feedback resistor (on the resistor network in the HR8 assembly) can cause an output error becauseof the finit...

5700A/5720A Series II Calibrator Service Manual 2-90 ahp020f.eps Figure 2-22. Power Amplifier Simplified Schematic

Theory of Operation Analog Section Detailed Circuit Description 2 2-91 2-149. PA Operation: 220V AC Range During ac operation, Power Amplifier gain is -10 as determined by the 4.99 k Ω input resistor R17, and 49.9 k Ω feedback resistors (R11 + R12 + R13). Control line SW3 turns Q50 on, which referen...

5700A/5720A Series II Calibrator Service Manual 2-92 is configured the same as for 220V ac operation, except that the input is the square-wavesignal HVCL from the High Voltage Control assembly, rather than OSC OUT HI,through relays K13B and K10A. 2-153. 220V DC Internal Calibration Network The 220V ...

Theory of Operation Analog Section Detailed Circuit Description 2 2-93 ahp021f.eps Figure 2-23. Power Amplifier DC Calibration Network

Theory of Operation Analog Section Detailed Circuit Description 2 2-95 f2-24.eps Figure 2-24. Power Amplifier Calibration AC Attenuator

5700A/5720A Series II Calibrator Service Manual 2-96 2-155. High Voltage Assemblies (A14 and A15) The High Voltage/High Current assembly (A15) and the High Voltage Control assembly(A14) are used in with conjunction with other assemblies in the calibrator to generate the±1100V dc, 1100V ac, and the 2...

Theory of Operation Analog Section Detailed Circuit Description 2 2-97 ahp022f.eps Figure 2-25. High Voltage/High Current Assembly 1100V AC Range

5700A/5720A Series II Calibrator Service Manual 2-98 2-157. 1100V DC Range Refer to Figure 2-26 for the following discussion. The High Voltage assembly (A15)amplifies the output of the DAC assembly (A11), set to the 11V range, by a gain of -100to generate the 1100V dc range. For operation in the 110...

Theory of Operation Analog Section Detailed Circuit Description 2 2-99 ahp023f.eps Figure 2-26. High Voltage/High Current Assembly 1100V DC Range

5700A/5720A Series II Calibrator Service Manual 2-100 When the DAC assembly is set to the +11V range, the output from the High Voltageassembly (with a gain of -100) is in the -1100V range. In this mode, -SP C is connectedto the collector of transistor Q3. The output from the dc HV amplifier follows ...

5700A/5720A Series II Calibrator Service Manual 2-102 Resistor network Z5 and hybrid H4 determine the performance of the 2.2A range.Current from the A7 assembly develops a voltage across the 57W portion of Z5. The2.2A current amplifier circuit forces the same voltage across the 0.57W portion of Z5.B...

5700A/5720A Series II Calibrator Service Manual 2-108 The signal/polarity selection circuit generates the ERROR SIGNAL used by the erroramplifier. It contains op amp U2C, CMOS analog switch U6, and resistor R35-R39.Control line V/I controls U6B and U6C which select the VI± when in the current mode.C...

5700/5720A Series II CalibratorService Manual Figure 2-30. Ohms Assemblies Simplified Schematic ahp38f.eps 2-110

2 Theory of Operation Analog Selection Detailed Circuit Description a h p 3 9 f . e p s 2-111 Figure 2-31. Ohms Main Assembly Simplified Schematic

5700A/5720A Series II Calibrator Service Manual 2-112 2-171. Ohms Main Assembly Support of Current Function Calibration To calibrate the current function, the Current assembly routes output current to the OhmsMain assembly, where it is connected through a resistance. Current is determined bymeasurin...

Theory of Operation Analog Section Detailed Circuit Description 2 2-113 Lines PC0-PC3 of port C go to decoder U13 and to the Ohms Main assembly. DecoderU13 enables two latch/driver ICs at a time. Setting the enable true (0V) causes the relaycoils to be driven on or off depending on the contents of t...

5700A/5720A Series II Calibrator Service Manual 2-116 ahp028f.eps Figure 2-33. Calibration to an External 10 k Ω Standard

Theory of Operation Analog Section Detailed Circuit Description 2 2-117 2-181. Calibrating to the External 10 KW Standard Refer to Figure 2-33 for the following discussion. The first step in ohms calibration is tocompare the 10 k Ω standard against the 10 k Ω value on the Ohms Cal assembly. This is ...

5700A/5720A Series II Calibrator Service Manual 2-118 OHMS SENSE HI is connected to INT SENSE HI by K16 and K2 on the Ohms Mainassembly. INT SENSE HI is connected to the SENSE HI binding post by relay K2 on themotherboard which is the sense high side of the 10 k Ω external standard. The ratio of thi...

Theory of Operation Analog Section Detailed Circuit Description 2 2-121 2-185. Calibrating to the External 1W Standard The 1 Ω and 1.9 Ω resistor values are calibrated by comparing them against a 1 Ω external standard. The technique used is different from that used for the 10 k Ω external standard. ...

5700A/5720A Series II Calibrator Service Manual 2-122 Relay driver U11 controls the three non-latching relays K14, K15, and K17 on thisassembly. It also generates control line RLY11* to control K11 on the Motherboard.Relay K11 routes I-GUARD, described later, to the rear panel for operation when the...

Theory of Operation Analog Section Detailed Circuit Description 2 2-123 ahp030f.eps Figure 2-35. Current Output Simplified Schematic

Theory of Operation Analog Section Detailed Circuit Description 2 2-125 Table 2-15. Relay Settings for Current Range Selection Relay Range 220 µ A 2.2 mA 22 mA 220 mA K5 R S S S K6 R S R R K7 R S R R K8 R R S R K9 R R R S S=SET R=RESET 2-192. Feedback Loop The output current develops a 2.2V full-sca...

5700A/5720A Series II Calibrator Service Manual 2-126 Internal calibration of the 2.2A range and gain of the High Voltage/High Currentassembly is discussed further in the theory for the High Voltage assemblies. 2-195. Current Guard Buffer Buffer amplifier U4, configured as a voltage follower, is use...

Theory of Operation Analog Section Detailed Circuit Description 2 2-127 ahp031f.eps Figure 2-36. Current Assembly Calibration

5700A/5720A Series II Calibrator Service Manual 2-128 amplifier is connected to RCL, which is routed to the adc circuit on the DAC assembly.The adc circuit measures the voltage, which is the drop across the 100 Ω resistor with no current applied through it. This value is the checkpoint reading and i...

5700A/5720A Series II Calibrator Service Manual 2-134 Oscillator Output assembly theory of operation for a detailed description on thegeneration of P SHIFT. Resistor R18 serves as overcurrent protection for the BNC shellconnection on J5. 2-213. Rear Panel Relay Control The relays on the Rear Panel a...

Theory of Operation Analog Section Detailed Circuit Description 2 2-135 • Seven control lines which comprise the CONTROL BUS • A low-level 3.6864 MHz clock (CLOCK, CLOCK*) • Eight data lines RPD0-RPD7 Interfacing between the Rear Panel data bus (D100-D107) and the CPU data bus (RPD0-RPD7) is done wi...

Theory of Operation Analog Section Detailed Circuit Description 2 2-137 The vco frequency is controlled by varactor diodes, CR1 + CR2, which get their biasvoltage from amplifier U2. Amplifier U2, which gets its input from the phase detectoroutputs (0V and 0R) of U1, changes the bias on varactor diod...

5700A/5720A Series II Calibrator Service Manual 2-138 and C112. FET Q105 is turned on, in the same manner as FET Q101, to connect the sinewave output of this filter to FILTER OUTPUT. This is applied to output driver transistorQ7. To obtain the required amount of filtering over the entire octave rang...

Theory of Operation Analog Section Detailed Circuit Description 2 2-139 ahp032f.eps Figure 2-37. Wideband Output Assembly Simplified Schematic

5700A/5720A Series II Calibrator Service Manual 2-140 2. The second range is for operation at frequencies between 12 kHz and 1.1 MHz. Inthis mode the input signal is also from the Oscillator Output assembly, but theamplitude is controlled by the amplitude control circuit on the Wideband Outputassemb...

Theory of Operation Analog Section Detailed Circuit Description 2 2-141 2-224. Wideband Output Attenuators The 10 Hz to 30 MHz sine wave signal output of the power amplifier circuit connects tothe 50 Ω output attenuator composed of attenuator networks Z1 and Z2 and relays K4, K5, K6, K7, and K8. Rel...

5700A/5720A Series II Calibrator Service Manual 2-142 sensor from damage by shunting its input and output to ground through the 200 Ω resistors R2 and R18. The negative voltage at the output of U4A also turns off transistor Q1 and causes controlline U9 ENABLE to go high. This disables relay driver U...

3-1 Chapter 3 Calibration and Verification Title Page 3-1. Introduction .......................................................................................... 3-3 3-2. Accessing the Fuse ............................................................................... 3-4 3-3. Cleaning the Air Fil...

5700A/5720A Series II Calibrator Service Manual 3-4 3-2. Accessing the Fuse The fuse is accessible from the rear panel. The fuse rating label to the right of the fuseholder shows the correct replacement fuse ratings for each operating voltage. To accessthe fuse, refer to Figure 3-1 and proceed as fo...

Calibration and Verification Cleaning the Air Filter 3 3-5 3-3. Cleaning the Air Filter Caution Damage caused by overheating may occur if the area aroundthe fan is restricted, the intake air is too warm, or the air filterbecomes clogged. The air filter must be removed and cleaned at least every 30 d...

5700A/5720A Series II Calibrator Service Manual 3-6 3-4. Cleaning the Exterior To keep the calibrator looking like new, clean the case, front panel keys, and lens using asoft cloth slightly dampened with either water or a non-abrasive mild cleaning solutionthat is not harmful to plastics. Caution Do...

Calibration and Verification Calibrating the 5700A/5720A Series II to External Standards 3 3-7 3-7. Calibration Requirements Both the calibrator and the recommended external standards have the ability to internallycontrol (or compensate for) ambient temperature variations. Therefore it is unnecessar...

5700A/5720A Series II Calibrator Service Manual 3-8 3-9. Calibration Procedure Before you being this procedure make sure the calibrator is powered on and hascompleted the appropriate warm-up period. After you have finished calibration, but before you save the new constants, the calibratorpresents th...

Calibration and Verification Calibrating the 5700A/5720A Series II to External Standards 3 3-9 4. Enter the ambient temperature; then press E . The display shows: PREV MENU IF3-4.EPS 5. Connect the 732B to the calibrator as shown in Figure 3-3. 732B DC STANDARD AC PWR IN CAL CHARGE LOW BAT 10V 1.018...

5700A/5720A Series II Calibrator Service Manual 3-10 6. Enter the true value of the 732B 10V output. The true value is the value printed onthe calibration sticker, plus or minus, as well as drift that has occurred sincecalibration. That drift can be estimated provided control charts have been mainta...

Calibration and Verification Calibrating the 5700A/5720A Series II to External Standards 3 3-13 11. Disconnect the 10 k Ω standard, and connect the calibrator to the 1 Ω standard; then enter the true value of the 1 Ω standard. If the standard is not between 0.9 Ω and 1.1 Ω , an error message appears...

5700A/5720A Series II Calibrator Service Manual 3-14 3-10. Range Calibration Once calibration is complete, you may find you need to make further adjustments to therange. Calibrating the range is accomplished by adjusting a range constant, which is anadditional gain multiplier. Although range calibra...

Calibration and Verification Range Calibration 3 3-15 PREV MENU IF3-2.EPS 3. Press the “Range Adjust” softkey to bring up the next menu shown below: PREV MENU IF3-18.EPS 4. Press the “DC V” softkey to bring up the next menu shown below: PREV MENU IF3-19.EPS 5. Press the “NEXT Menu” softkey, which sc...

Calibration and Verification Calibrating the Wideband AC Module (Option 5700A-03) 3 3-17 OUTPUT V A SENSE VA AUX CURRENT GUARD GROUND WIDEBAND NC HI HI HI LO LO LO OUTPUT HI LO GND GRD 752A VOLTAGE DIVIDER STANDARD INPUT REFERENCE STANDARD NULL DETECTOR HI LO GUARD GND NULL DETECTOR HI LO HI HI LO 7...

5700A/5720A Series II Calibrator Service Manual 3-18 Since frequency flatness is determined by stable parameters (i.e. circuit geometry anddielectric constants), the flatness of the Wideband AC Module has excellent long-termstability. Consequently, a two-year calibration cycle is adequate for flatne...

Calibration and Verification Calibrating the Wideband AC Module (Option 5700A-03) 3 3-19 HI HI LO LO HI OUTPUT V A SENSE V AUX CURRENT GUARD GROUND WIDEBAND Ω GND TAB 50 FEEDTHROUGH Ω Ω CALIBRATOR F7-5.EPS Figure 3-6. Wideband Module Calibration Connection 4. Press the “Gain” softkey to bring up the...

5700A/5720A Series II Calibrator Service Manual 3-20 6. Reverse the dual-banana connector so that the center connector is connected to LO;then press E . The display shows the following: PREV MENU IF3-16.EPS After a short time, a message appears indicating that the wideband calibration iscomplete. 7....

Calibration and Verification Performing a Calibration Check 3 3-21 PREV MENU IF3-3.EPS 3. Enter the ambient temperature; then press E . As the calibration check proceeds, the display indicates the current process of the calibration check. When thecheck is complete, the largest shift that is detected...

5700A/5720A Series II Calibrator Service Manual 3-22 3-13. Full Verification An independent external verification is recommended every two years, following normalperiodic calibration or repair of the calibrator. Verification establishes and maintainsparallel external traceability paths for the inter...

Calibration and Verification Full Verification 3 3-23 In Figure 3-7, the location of each test is identified by the paragraph numbers. 3-14. Required Equipment for All Tests An abbreviated summary of required equipment for all the verification and optional testsis given in Table 3-2. Individual list...

Calibration and Verification Full Verification 3 3-25 3-16. Resistance Verification Test The following test requires testing at the high, low and intermediate values only. This isbecause the 5700A/5720A Series II creates the other values of resistance from thesevalues. Use Tables 3-16 (5720A) and 3-...

5700A/5720A Series II Calibrator Service Manual 3-26 INPUT SENSE HI LO HI LO DMM OUTPUT SENSE HI LO HI LO CALIBRATOR (UUT) CURRENT SENSE HI LO HI LO OUTPUT HI LO CURRENT SOURCE 742A-X F3-5.EPS Figure 3-8. 1 Ohm and 10 Ohm Resistor Verification Note There is no need to do the cal current calculation ...

Calibration and Verification Full Verification 3 3-27 Table 3-4. Low Value Resistance Calibration Using a Current Source 5720A (UUT) Resistance Apply Current 5720A Deviation From Displayed Value (90-day) 5720A Displayed Value 1 Ω 100 mA ± 95 ppm 0.9995 to 1.0005 1.9 Ω 100 mA ± 95 ppm 1.89905 to 1.90...

5700A/5720A Series II Calibrator Service Manual 3-28 3-18. DC Voltage Verification Test The following test checks every dc voltage range by testing the output accuracy atdecade values of voltage from 100 mV to 1000V. Use Table 3-18 (5720A) or Table 3-19(5700) for the test record. Table 3-5 lists equ...

5700A/5720A Series II Calibrator Service Manual 3-30 3-20. Direct Current Accuracy Verification Test Equipment required for the Direct Current Accuracy Verification Test is listed in Table3-6. Proceed as follows to test accuracy of the dc current function: Table 3-6. Equipment Required for Direct Cu...

Calibration and Verification Full Verification 3 3-31 5. Algebraically add column B to column A. Enter the result on the test record. Verifythat it is within the test limits shown. 6. Repeat steps 2 through 5 using the Fluke 742A Resistance Standards and Calibratoroutput currents shown in Tables 3-2...

Calibration and Verification Full Verification 3 3-33 Table 3-8. 5790A Adjustment Counts 5700A/5720A Series II Output Level 5790A Display 5790A Adjustment Counts* 2 mV 2.0000 ± 1 20 mV 20.0000 ± 1 200 mV 200.0000 ± 4 2V 2.000000 ± 4 2.3V 2.30000 ± 1 20V 20.00000 ± 4 200V 200.0000 ± 4 300V 300.000 ± ...

5700A/5720A Series II Calibrator Service Manual 3-34 1. Connect the equipment as shown in Figure 3-12(A) use the 2A shunt. 2. Enter the ac to dc difference corrections for each shunt at each frequency in theappropriate column of the test record (Table 3-26 or 3-27). 3. Set the Calibrator for a +2A d...

Calibration and Verification Full Verification 3 3-35 Note When verifying the 5725A Amplifier at the 10A level, allow sufficient timefor the A40A-10 shunt to reach thermal stability after initially applying thecurrent. A. Alternating Current Test Setup, 22 mA to 2A Using 5790A Input 1 Hi 5790A Input...

5700A/5720A Series II Calibrator Service Manual 3-36 3-24. AC Current Test, 2 mA and 200 µ A Ranges The equipment required for the alternating current accuracy verification test for the 2mA and 200 µ A ranges is listed in Table 3-10. Use Table 3-28 (5720A) or 3-29 (5700A0 for the test record. Table ...

Calibration and Verification Full Verification 3 3-37 9. Change the Calibrator frequency to 20 Hz, 40 Hz, 1 kHz, 5 kHz and 10 kHz. At eachfrequency record the error display on the 5790A in Table 3-28 or 3-29. Verify thatthe results are within limits shown. 10. Repeat steps 2 through 9, but replace t...

5700A/5720A Series II Calibrator Service Manual 3-38 Note The input impedance at INPUT 2 of the 5790A on the millivolt ranges is 10M Ω shunted by 83 pF and the cable used to connect the shunt resistor to the 5790A has 40 pF capacitance, for a total of 123 pF. The reactance of 123 pF at 10 kHz is 129...

Calibration and Verification Wideband Output Accuracy at 1 kHz Test 3 3-39 Table 3-11. Equipment Required for Testing and Calibrating the Wideband Option Equipment Model or Description AC Measurement Standard Fluke 5790A with Wideband Option -03 Wideband cable Supplied with 5700A-03 50 Ω Termination...

5700A/5720A Series II Calibrator Service Manual 3-40 Table 3-12. Wideband Adjustment Tolerance 5700A/5720A Series II Wideband Output 5790A Adjustment Counts ± ppm 2.10000V 20 1.00000V 10 300.000 mV 3 100.000 mV 10 30.0000 mV 3 10.0000 mV 1 3.00000 mV 1 1000.00 µ V 1 3-29. Wideband Output Flatness Te...

Calibration and Verification Wideband Output Flatness Test 3 3-41 3-30. Wideband Flatness Calibration Procedure This procedure is the only part of full verification that stores calibration constants in theCalibrator. This is not a verification test, it is a calibration procedure. Because this partof...

5700A/5720A Series II Calibrator Service Manual 3-42 21. Push the CLEAR REF WBND soft key on the 5790A. The 5790A wideband outputchanges to 10 mV at 1 kHz. 22. Push the SET REF soft key on the 5790A when the 5790A settles to a reading. Thisis the 10 mV reference value from which all other frequencie...

Calibration and Verification Optional Tests 3 3-43 3. Repeat load regulation testing at the remaining Calibrator outputs shown in Table3-47. 4. Set the Calibrator to standby and disconnect all equipment from the Calibrator. 3-33. DC Voltage Linearity Test Use Table 3-35 for a test record. Proceed as...

5700A/5720A Series II Calibrator Service Manual 3-44 LO OUTPUT SENSE HI CALIBRATOR (UUT) GRD GND SHIELDED TWISTED PAIR OUTPUT COAX TRUE RMS VOLTMETER VERTICAL OSCILLOSCOPE MAINFRAME* 7A22 PLUG-IN CLIP LEADS 3' APPROX GR BANANA PLUGS SHIELDED TWISTED PAIR CABLE DETAIL BNC OSCILLOSCOPE AND AC DIFFEREN...

Calibration and Verification Optional Tests 3 3-45 3-35. DC Voltage Output Noise ( 0 . 1 to 10 Hz ) Test Proceed as follows to test for dc voltage output noise in the range 0.1 to 10 Hz: 1. Place the 8520A DMM into Math Program 8 with the Display Option Register set toregister 8.3 (Standard Deviatio...

Calibration and Verification Minimum Use Requirements 3 3-47 Table 3-15. Minimum Use Requirements Item No. Description Minimum Use Specifications Recommended Equipment Calibration Equipment 1. Voltage Reference 10V nominal, true value certified to within ± 1.5 ppm Fluke 732B 2. Resistance Standards ...

5700A/5720A Series II Calibrator Service Manual 3-48 Table 3-15. Minimum Use Requirements (cont) Item No. Description Minimum Use Specifications Recommended Equipment 9. Current Shunt Adapter Used in conjunction with 5790A and A40-series shunts to facilitate AC Currentmeasurements Fluke 792A-7004 10...

Calibration and Verification Determining Test Limits for Other Calibration Intervals 3 3-49 Example 1 shows you how to calculate a specification limit for a specific test level froma specification listed as a percentage (or parts per million) of reading plus a floor error inmicrovolts, millivolts, m...

Calibration and Verification Determining Test Limits for Other Calibration Intervals 3 3-65 Table 3-30. Wideband Frequency Accuracy Test Record Frequency ( Hz ) Frequency Measured Tolerance Limits 10 Hz 99.99 ms to 100.01 ms 100 Hz 9.999 ms to 10.001 ms 300 Hz 299.97 Hz to 300.03 Hz 500 Hz 499.95 Hz...

Some semiconductors and custom IC's can bedamaged by electrostatic discharge duringhandling. This notice explains how you canminimize the chances of destroying such devicesby: 1. Knowing that there is a problem.2. Leaning the guidelines for handling them.3. Using the procedures, packaging, and bench...

4-1 Chapter 4 Maintenance Title Page 4-1. Introduction .......................................................................................... 4-3 4-2. Cleaning the Air Filter.......................................................................... 4-3 4-3. General Cleaning ........................

Maintenance Introduction 4 4-3 4-1. Introduction This section covers procedures that do not fall into the category of troubleshooting orrepair. This includes access procedures, installation of the Wideband module (Option -03), periodic cleaning, and other special service procedures. 4-2. Cleaning th...

5700A/5720A Series II Calibrator Service Manual 4-4 4-3. General Cleaning To keep the Calibrator looking like new, clean the case, front panel keys, and lens usinga soft cloth slightly dampened with water or a non-abrasive mild cleaning solution thatdoes not harm plastics. CAUTION Do not use aromati...

Maintenance Access Procedures 4 4-5 REMOVE Figure 4-2. Rear Panel Removal 4-10. Rear Panel Assembly Access Refer to Figure 4-3 during the following procedure: REMOVE REMOVE 1 REMOVE FACK SCREWS TO SEPARATE THE REAR PANEL CIRCUIT BOARD FROMTHE METAL HOUSING. 1 1 1 1 F4-3.EPS Figure 4-3. Rear Panel As...

5700A/5720A Series II Calibrator Service Manual 4-6 5. Remove P11 from J11. Then remove the two paddle board mounting screws andseparate the paddle board from the Rear Panel assembly. 6. Remove the jack screws for each connection on the rear panel housing, then gentlylift the Rear Panel assembly out...

Maintenance Access Procedures 4 4-7 4-13. Keyboard Assembly Removal and Installation The following procedure assumes that the Display Assembly Removal procedure hasalready been completed. 1. Remove all output cable connections (including GROUND-to-metal) from the frontpanel binding posts. Save all r...

5700A/5720A Series II Calibrator Service Manual 4-8 VOLTAGE SELECT SWITCHES RS232 A5 WIDEBAND OUTPUT PCA A6 WIDEBAND OSCILLATOR PCA A7 CURRENT/HIGH-RESOLUTION OSCILLATOR PCA A1 KEYBOARD ASSEMBLY A8 SWITCH MATRIX PCA A2 FRONT PANEL PCA A9 OHMS CAL PCA A10 OHMS MAIN PCA A11 DAC PCA A12 OSCILLATOR CONT...

Maintenance Front/Rear Binding Post Reconfiguration 4 4-9 4-15. Digital Assembly Removal and Installation Remove the CPU Assembly or the Digital Power Supply Assembly by pulling straightup at the top corners of the assembly. In relation to the chassis side, the CPU Assemblycomponents face toward, an...

5700A/5720A Series II Calibrator Service Manual 4-10 Reverse this procedure when changing from rear to front output operation. 1. Remove instrument top and bottom covers and remove bottom analog guard cover. 2. Remove the instrument front panel by removing the three hex screws on each fronthandle si...

Maintenance Installing a Wideband AC Module (Option -03) 4 4-11 4-19. Installing a Wideband AC Module (Option -03) CAUTION The Wideband option circuit board assemblies contain static-sensitive components. Use caution to avoid static dischargewhen handling the modules. The procedure that follows can ...

5700A/5720A Series II Calibrator Service Manual 4-12 2. Follow the access procedures to remove the digital side cover. 3. Remove the CPU Assembly (A20). 4. Desolder and remove battery BT1. 5. Solder a replacement battery in place (refer to the parts list for replacementinformation if necessary.) 6. ...

Maintenance Using Remote Commands Reserved for Servicing 4 4-13 FATALITY? Description: Returns the list of the fatal faults logged since the list was last cleared by theFATALCLR command. (Sequential command.) Parameter: None Response: (String) The list of faults, one per line in the following format...

5-1 Chapter 5 Troubleshooting Title Page 5-1. Introduction .......................................................................................... 5-3 5-2. Interpreting Diagnostic Fault Codes..................................................... 5-3 5-3. Component-level Troubleshooting ..............

Troubleshooting Introduction 5 5-3 5-1. Introduction Information in this section begins with guidance in using self-diagnostics fault codes toisolate a faulty module. The descriptive text helps to quickly locate the source of a fault.Further on, under Component Level Troubleshooting, techniques for ...

5700A/5720A Series II Calibrator Service Manual 5-4 2704 Spare This fault code is not used. 2705 A7: Oven Regulation Fault The heater voltage of the current hybrid is measured by dividing OVEN TEMP downand connecting it to the SDL line where it is measured by the adc circuit on the DACassembly to en...

Troubleshooting Interpreting Diagnostic Fault Codes 5 5-5 2713 A7: Hi-Res Loop In 100Hz Range The instrument is set for 2.0V at 100 Hz operation. The input voltage to the VCO circuitis resistively divided to create the control line HI-RES LOOP. HI-RES LOOP isconnected to the SDL line where it is mea...

5700A/5720A Series II Calibrator Service Manual 5-6 2801 A11: 8255 Port a Wires The diagnostics software writes and reads data to port A of the 8255 IC on the DACassembly. A failure indicates the DAC assembly (A11) is probably at fault. 2802 A11: 8255 Port B Data Bus The diagnostics software reads p...

Troubleshooting Interpreting Diagnostic Fault Codes 5 5-11 3109 A15: HV +DC Preamplifier Fault The instrument is set to the dc 1100V range with the amplitude set to 220V, 600V, and1100V. The output of the DC HV AMPLIFIER/AC SENSE BUFFER circuit of the HighVoltage/High Current assembly is measured fo...

5700A/5720A Series II Calibrator Service Manual 5-12 line for measurement by the adc circuit on the DAC assembly. This failure occurs if theexpected output voltage is not within 12% of the nominal. 3116 A15: HV -DC Reference/error Amp Fault The instrument is set to the dc 1100V range with the amplit...

5700A/5720A Series II Calibrator Service Manual 5-16 3140 A14/A15/A16: 2.2A AC Range Abs. Value The instrument is configured to the ac 2.2A range and set for an output current of 0.22Aat 1 kHz, 0.6A at 1 kHz, 1.1A at 1 kHz, 0.6A at 40 Hz, and 1.1A at 50 Hz. The outputcurrent from the High Voltage/Hi...

Troubleshooting Interpreting Diagnostic Fault Codes 5 5-29 hybrid is warmed up and regulating. The heater voltage is measured to be 0.7V ±10%±0.2V. A failure indicates the Power Amplifier assembly (A16) is probably at fault. 3521 Assembly A16 Is Not Responding At power up the instrument checks to se...

Troubleshooting Interpreting Diagnostic Fault Codes 5 5-35 3808 A8: Zero Amp Hi Offset The Internal Cal Zero Amplifier circuit on the Switch Matrix assembly is tested forexcessive offset in the high gain configuration. This is done by connecting the circuitinput to RCOM, by turning on Q7, and connec...

5700A/5720A Series II Calibrator Service Manual 5-36 3822 Spare This fault code is not used. 3823 Spare This fault code is not used. 3824 A8: Oven Regulation Fault The heater voltage of the Switch Matrix HR1 hybrid assembly is measured to ensure it iswarmed up and regulating by connecting OVEN TEMP ...

5700A/5720A Series II Calibrator Service Manual 5-38 level it is checked for 0.0V ±0.7V. A failure indicates the Wideband Output (A5)assembly is probably at fault. 3911 A5/A6: Ampl. Control At 30MHz The Wideband assemblies are configured for a 3.5V and 1.2V output at 30.0 MHz. WBAMPLITUDE CONTROL wh...

Troubleshooting Interpreting Diagnostic Fault Codes 5 5-39 3916 A5: 20DB Output Attenuation Fault The 6.5V reference (BRF6, BSRF6) is connected to the Unity Gain Amplifier circuit onthe Wideband Output assembly which drives the output through the Attenuators. TheWideband Output assembly is set for 2...

5700A/5720A Series II Calibrator Service Manual 5-40 3923 A5: 8255 Was Reset The control word of the 8255 on the Wideband Output is read. A failure indicates theWideband Output (A5) assembly is probably at fault. 5-3. Component-level Troubleshooting Warning Servicing described in this section is to ...

Troubleshooting Component-level Troubleshooting 5 5-41 voltage at TP2 and verify it is 0.317 times the voltage at TP1 ±10%. If a failure isdetected, check U5 and associated components. Note During Wideband operation, internal software monitors the output andmakes corrections or trips the instrument ...

5700A/5720A Series II Calibrator Service Manual 5-42 voltages of 3V, 1V, 300 mV, and 30 mV, all at 1 kHz, and verify the DMM read theselected voltage ±5%. If a failure is detected, check K4-K8, Z1, and Z2. Next,connect the supplied output cable and 50 Ω terminator to the WIDEBAND connector of the Ca...

5700A/5720A Series II Calibrator Service Manual 5-46 switches to a high(~+17V) level while all the others remain at a low (-11V) level. Ifa failure is detected, check U8, U10, U11, and U13. 14. Check the Filters. Disconnect the cable between the Wideband Oscillator assemblyand Wideband Output assemb...

Troubleshooting Component-level Troubleshooting 5 5-47 5-6. Troubleshooting the Current/Hi-Res Assembly (A7) The Current/Hi-Res assembly generates output current and contains the high-resolutionoscillator onto which the Oscillator Control assembly phase locks. Since these twofunctions are independen...

5700A/5720A Series II Calibrator Service Manual 5-48 1 V 10 ms F5-6.EPS Figure 5-6. Waveform at Pin 11 of K2 4. Check the 220 µ A range of the 220 µ A/2.2 mA AMP circuit. Set the Calibrator to 200 µ A, standby. Set the external ac reference to 6.4V(±0.1V) at 1 kHz. Using a DMM, measure the ac voltag...

Troubleshooting Component-level Troubleshooting 5 5-49 1 V 10 ms F5-7.EPS Figure 5-7. Waveform at Pin 6 of K2 10 k HR2 SHUNT 1.2 R14 2V ac±10% K5C, K5D, K10, K13 SCOM Ω Ω F5-8.EPS Figure 5-8. Verifying the 220 µ A Range of the 220 µ A/2.2 mA Amp Circuit 5. Check the 2.2 mA Range of the 220 µ A/2.2 m...

5700A/5720A Series II Calibrator Service Manual 5-50 10 k HR2 SHUNT 1.2 R14 2V ac±10% K7C, K5D, K10, K13 SCOM Ω Ω F5-9.EPS Figure 5-9. Verifying the 2.2 mA Range of the 220 µ A /2.2 mA Amp Circuit 10 k HR2 SHUNT 1.2 R14 2V ac±10% K8C, K7A, K5, K10, K13 SCOM Ω Ω F5-10.EPS Figure 5-10. Verifying the 2...

5700A/5720A Series II Calibrator Service Manual 5-52 5-8. Hi-Res Oscillator Section Proceed as follows to troubleshoot the Hi-Res Oscillator Section of the Current/Hi-Resassembly (A7): 1. Remove the four small shields (two on each side) and place the Current/Hi-Resassembly on the analog reverse exte...

5700A/5720A Series II Calibrator Service Manual 5-54 1 V 10 ms F5-14.EPS Figure 5-14. Waveform at TP13 8. Check the LOOP FILTER circuit. Power down the Calibrator, cut jumper E2 andconnect an external variable dc reference (2 to 12V) to TP11(common to TP18).Power up the Calibrator and set it for 2V ...

5700A/5720A Series II Calibrator Service Manual 5-58 Note The connection from the test points to the resistance values is throughlatching type relays for all resistances except 10M, 19M, and 100 M Ω values. These relays are put in the set or reset position and remain in thatposition even after power...

Troubleshooting Component-level Troubleshooting 5 5-63 14. Check the DAC 20V Range. Set the Calibrator to 20V dc, operate. Using a DMMmeasure the DAC output voltage at TP8 (common to TP3). It should be a nominal20V dc (±0.5V for an uncalibrated instrument). If a failure is detected, check Q14,Q15, Q...

Troubleshooting Component-level Troubleshooting 5 5-67 1 V 10 ms F5-26.EPS Figure 5-26. Waveform at Pin 7 of U12 5-15. ADC Circuit Proceed as follows to troubleshoot the ADC circuit: 1. Check the ADC INPUT select circuit. Set the Calibrator to 10V dc, operate. Verifythat the voltage at U23 pin 7 (co...

Troubleshooting Component-level Troubleshooting 5 5-71 the input to the AC/DC sensor. The oscilloscope display should be switchingbetween Figure 5-29, which is the output of the DC SENSE BUFFER circuit andFigure 5-30, which is the output of the AC SENSE BUFFER circuit. If either ofthese signals is i...

5700A/5720A Series II Calibrator Service Manual 5-72 1 V 10 ms F5-30.EPS Figure 5-30. AC Sense Buffer Waveform at TP6 5-18. Troubleshooting the Oscillator Output Assembly (A13) Note During normal Calibrator operation, internal software monitors the outputand makes corrections or trips the instrument...

Troubleshooting Component-level Troubleshooting 5 5-73 4. Next, jumper the input of the SUMMING AMPLIFIER to the -5S supply and checkthe following: • TP5: positive voltage • TP4: negative voltage • TP3: positive voltage • Pin 6 of U8: positive voltage 5. Repair any amplifier circuits which are not p...

Troubleshooting Component-level Troubleshooting 5 5-79 1 V 10 ms F5-32.EPS Figure 5-32. Waveform at Pin 18 of Hybrid H4 13. Connect an oscilloscope to pin 7 of U3B and verify it displays a square wave equalto the positive peaks of Figure 5-32. Next, connect the oscilloscope to pin 1 of U3Aand verify...

5700A/5720A Series II Calibrator Service Manual 5-80 1. Power up the Calibrator. In the following steps, reference all measurements toPACOM (TP10) unless otherwise Noted. 2. Set the Calibrator to 22V at 1 kHz, operate. This configures the Power Amplifierassembly as an amplifier with a gain of -10 as...

5700A/5720A Series II Calibrator Service Manual 5-82 DMM, measure the voltage at U9 pin 6 and verify it is the equal to the voltage atTP12 divided by 8 ±1%. If a failure is detected, check the HR8 resistor network, U9,and the associated components. 5-23. Troubleshooting the Filter/PA Supply Assembly...

6-1 Chapter 6 List of Replaceable Parts Title Page 6-1. Introduction .......................................................................................... 6-36-2. How to Obtain Parts ............................................................................. 6-36-3. Manual Status Information ...

List of Replaceable Parts Service Centers 6 6-5 Table 6-1. Front Panel Final Assembly Reference Designator Description Fluke Stock No Tot Qty Notes A1 * KEYBOARD PCA 761049 1 A2 * FRONT PANEL PCA 761031 1 A3 * ANALOG MOTHERBOARD PCA 761023 1 A4 * DIGITAL MOTHERBOARD PCA 760942 1 A7 * CURRENT/HIGHT R...

5700A/5720A Series II Calibrator Service Manual 6-48 Table 6-14. A11A2 DAC Buffered Reference SIP PCA Reference Designator Description Fluke Stock No Tot Qty Notes C1,C5 CAP,CER,10PF,+-10%,100V,C0G,1206 806943 2 C2,C3 CAP,CER,0.22UF,+80-20%,50V,Y5V 740597 2 C4,C6 CAP,CER,1000PF,+-10%,50V,C0G,1206 74...

List of Replaceable Parts Service Centers 6 6-49 5700A-1644 57001644.EPS Figure 6-16. A11A2 DAC Buffered Reference SIP PCA

5700A/5720A Series II Calibrator Service Manual 6-58 Table 6-17. A13A1 Oscillator Wideband SMD PCA Reference Designator Description Fluke Stock No Tot Qty Notes C1,C3,C4,C6-8,C12,C13 CAP,CER,0.22UF,+80-20%,50V,Y5V 740597740597 8 C2 CAP,CER,100PF,+-10%,50V,C0G,1206 740571 1 C5 CAP,CER,10PF,+-10%,100V...

List of Replaceable Parts Service Centers 6 6-59 5700A-1652 57001652.EPS Figure 6-19. A13A1 Oscillator Wideband SMD PCA

5700A/5720A Series II Calibrator Service Manual 6-62 5700A-1661 57001661.EPS Figure 6-20. A14 High Voltage Control PCA

5700A/5720A Series II Calibrator Service Manual 6-70 Table 6-21. A16A1 Power Amplifier Digital Control SIP PCA Reference Designator Description Fluke Stock No Tot Qty Notes C52 CAP,AL,15UF,+-20%,35V 614024 1 C53,C56 CAP,CER,33PF,+-5%,50V,C0G 714543 2 C54 CAP,CER,470PF,+-10%,50V,C0G 733071 1 C55,C57 ...

List of Replaceable Parts Service Centers 6 6-71 5700A-1671 Figure 6-23. A16A1 Power Amplifier Digital Control SIP PCA

List of Replaceable Parts Service Centers 6 6-81 5700A-1604 57001604.EPS Figure 6-26. A19 Digital Power Supply PCA

5700A/5720A Series II Calibrator Service Manual 6-82 Table 6-25. A20 CPU PCA Ref Des Description Part Number Qty C1 CAPACITOR SMR,CAP,TA,220UF,+-20%,10V,7343H 106021 1 C2-4,C6-7 C14-16 C18, C101-111, C113, C115, C116, C119- 120, C125- 133, C142- 143, C152 CAPACITOR SMR,CAP,CER,0.1UF,+-10%,50V,X7R,08...

7-1 Chapter 7 Schematic Diagrams Figure Title Page 7-1. A1 Keyboard Assembly ......................................................................... 7-3 7-2. A2 Front Panel PCA ............................................................................... 7-5 7-3. A3 Analog Motherboard PCA..........