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vii

List of Figures

Figure

Title

Page

1-1. 8508A Dimentional Outline Drawing .................................................................... 1-6

2-1. 8508A Functional Block Diagram ......................................................................... 2-4

2-2. Power Supplies - Simplified Block Diagram ......................................................... 2-7

3-1. Equipment Connections Required for Calibration ................................................. 3-13

4-1. Internal Wiring and Cabling Diagram.................................................................... 4-4

4-3. Removing the A2 AC PCA .................................................................................... 4-6

4-4. Removing the A3 Ohms PCA ................................................................................ 4-7

4-5. Removing the A4 Digital PCA............................................................................... 4-8

4-6. Removing the A5 Bezel Assembly ........................................................................ 4-9

4-7. Removing the A5A1 Display PCA ........................................................................ 4-10

4-8. Removing the A6 Rear Input Assembly ................................................................ 4-11

4-9. Rear Panel - Power Input Fuse and line Power Locations ..................................... 4-12

5-1. 8508A Final Assembly........................................................................................... 5-5

5-2. 8508A Chassis Assembly....................................................................................... 5-7

5-3. A5 Bezel (front panel) Assembly........................................................................... 5-11

5-4. Rear Input Assembly (optional) ............................................................................. 5-14

Содержание 8508A

Страница 1: ...e Multimeter Service Manual September 2004 Rev 1 8 08 2004 2008 Fluke Corporation All rights reserved Specifications are subject to change without notice All product names are trademarks of their respective companies ...

Страница 2: ...tain return authorization information then send the product to that service center with a description of the difficulty postage and insurance prepaid FOB Destination Fluke assumes no risk for damage in transit Following warranty repair the product will be returned to Buyer transportation prepaid FOB Destination If Fluke determines that failure was caused by neglect misuse contamination alteration ...

Страница 3: ...C Voltage 1 9 DC Current 1 10 AC Voltage 1 11 AC Current 1 13 Resistance 1 15 Temperature 1 17 Read Rate and Additional Uncertainty 1 18 Applying the Specifications 1 19 Introduction 1 19 Absolute and Relative Specifications 1 19 Applying User s Calibration Uncertainties 1 20 Operating and Calibration Temperature Ranges 1 20 Applying Temperature Coefficient Specifications 1 20 Ratio Measurements 1...

Страница 4: ...bration 3 14 DC Voltage Calibration 3 14 AC Voltage Calibration 3 16 Resistance Calibration 3 18 DC Current Calibration 3 25 AC Current Calibration 3 27 Frequency Calibration 3 28 Exit From Calibration Mode and Non Volatile Input Offset Adjustment 3 29 Cal Due Date Entry and Calibration Mode Disable 3 30 ACV Spot Frequency Calibration 3 30 Performance Verification 3 31 Equipment Requirements 3 32 ...

Страница 5: ...t and Line Voltage Selection 4 12 Line Power Fuse F1 and Voltage Selection 4 12 Rear Input Current Fuse F2 Rear Inputs Option 4 13 Self Test 4 13 Self Test Errors 4 13 Fatal Errors 4 16 Execution Errors 4 18 Device Dependant Errors 4 19 5 List of Replaceable Parts 5 1 Introduction 5 3 How to Obtain Parts 5 3 How to Contact Fluke 5 3 Parts Lists 5 4 ...

Страница 6: ...8508A Service Manual iv ...

Страница 7: ... 9 AC Voltage Verification Points and Sequence 3 36 3 10 Resistance Verification Points and Sequence 3 39 3 11 DC Current Verification Points and Sequence 3 41 3 12 AC Current Verification Points and Sequence 3 42 4 1 Power Input Fuse 1 4 12 4 2 Current Function Rear Input Fuse 2 4 13 4 3 Self Test Errors 4 13 4 4 9000 System Kernel Fault Errors 4 16 4 5 Unexpected Exception Errors 4 16 4 6 Serial...

Страница 8: ...8508A Service Manual vi ...

Страница 9: ...and Cabling Diagram 4 4 4 3 Removing the A2 AC PCA 4 6 4 4 Removing the A3 Ohms PCA 4 7 4 5 Removing the A4 Digital PCA 4 8 4 6 Removing the A5 Bezel Assembly 4 9 4 7 Removing the A5A1 Display PCA 4 10 4 8 Removing the A6 Rear Input Assembly 4 11 4 9 Rear Panel Power Input Fuse and line Power Locations 4 12 5 1 8508A Final Assembly 5 5 5 2 8508A Chassis Assembly 5 7 5 3 A5 Bezel front panel Assemb...

Страница 10: ...8508A Service Manual viii ...

Страница 11: ...d AC Current 1 8 Resistance and Temperature 1 8 DC Voltage 1 9 DC Current 1 10 AC Voltage 1 11 AC Current 1 13 Resistance 1 15 Temperature 1 17 Read Rate and Additional Uncertainty 1 18 Applying the Specifications 1 19 Introduction 1 19 Absolute and Relative Specifications 1 19 Applying User s Calibration Uncertainties 1 20 Operating and Calibration Temperature Ranges 1 20 Applying Temperature Coe...

Страница 12: ...8508A Service Manual 1 2 ...

Страница 13: ...rpose of the descriptions is to assist with equipment repairs at the PCA level Chapter 5 List of Replaceable Parts provides all of the information required to identify and order replacement parts for repairing the Multimenter at the PCA level XW Warning To avoid electric shock personal injury or death carefully read the information under Safety Considerations before attempting to install use or se...

Страница 14: ...ly more than the rated voltage as marked on the Multimeter between the terminals or between any terminal and earth ground Always use the power cord and connector appropriate for the voltage and outlet of the country or location in which you are working Remove test leads from the Multimeter before opening the case Never remove the cover or open the case of an instrument without first removing the p...

Страница 15: ... X Hazardous voltage Voltage 30 V dc or ac peak might be present J Earth ground B AC Alternating Current CAT IEC 61010 Overvoltage installation or measurement Category F DC Direct Current I Fuse D or C AC or DC Alternating or Direct Current Do not dispose of this product as unsorted municipal waste Go to Fluke s website for recycling information H Digital signal Recycle Y Potentially hazardous vol...

Страница 16: ...mine which module PCA has a fault See Chapter 5 for cautions about handling the internal components How to Contact fluke To contact Fluke call one of the following telephone numbers USA 1 888 99 FLUKE 1 888 993 5853 Canada 1 800 36 FLUKE 1 800 363 5853 Europe 31 402 675 200 Japan 81 3 3434 0181 Singapore 65 738 5655 Anywhere in the world 1 425 446 5500 Or visit Fluke s Web site at www fluke com To...

Страница 17: ...PRF 28800F Class 3 Safety Designed and tested to EN61010 1 2001 UL 61010 1A1 CAN CSA C22 2 No 61010 1 CE and ETL marked Pollution Degree 2 Installation Category II Equipment Class I single insulation Earthed metal case Protection against water ingress IP4X general indoor conditions Input circuitry and connections creepage and clearances designed to interface at Installation or Measurement Category...

Страница 18: ...nected to Lo DC and AC Current Maximum rms terminal voltages Sense Hi Hi 250 V Sense Lo 1000 V 1000 V Lo 250 V 1000 V 1000 V A 5 V 250 V 1000 V 1000 V Guard 250 V 250 V 250 V 1000 V 1000 V DigGnd 650 V 650 V 650 V 650 V 1000 V 1000 V Ground 0 V 650 V 650 V 650 V 650 V 1000 V 1000 V Maximum rms terminal currents Guard A Lo Sense Lo Hi Sense Hi Front Input n a 20 A 20 A n a n a n a Rear input n a 2 ...

Страница 19: ... 0 25 3 5 0 25 4 0 0 25 4 5 0 25 200 V 199 990 000 1 2 0 25 3 5 0 25 5 2 0 25 6 0 0 25 7 0 0 25 1000 V 1050 000 00 1 2 0 6 3 5 0 6 5 2 0 6 6 0 0 6 7 0 0 6 DC Voltage Secondary Specifications 1 2 3 Temperature Coefficient 15 C 30 C 5 C 15 C 30 C 40 C Range Transfer Uncertainty 20 mins 1 C ppm Reading ppm Range ppm Reading C 200 mV 0 4 0 3 0 4 0 6 2 V 0 12 0 1 0 3 0 5 20 V 0 12 0 1 0 3 0 5 200 V 0 4...

Страница 20: ... 0 2 0 15 2 0 16 2 0 20 mA 19 999 000 8 0 2 0 9 0 2 0 10 2 0 16 2 0 18 2 0 200 mA 199 990 00 35 4 0 37 4 0 40 4 0 45 4 0 60 4 0 2 A 1 999 900 0 100 8 0 150 8 0 205 8 0 210 8 0 225 8 0 20 A 19 999 000 250 20 350 20 450 20 455 20 500 20 DC Current Secondary Specifications 1 2 3 Temperature Coefficient Input Impedance Ω 15 C 30 C 5 C 15 C 30 C 40 C Range Front Rear ppm Reading C 200 μA 150 150 0 4 0 ...

Страница 21: ...1 1000 V 8 1050 000 1 10 70 70 100 70 100 70 140 70 150 70 10 40 70 20 100 20 100 20 110 20 120 20 40 10 k 50 20 80 20 80 20 95 20 115 20 10 k 30 k 100 40 200 40 200 40 205 40 225 40 30 k 100 k 250 200 500 200 500 200 510 200 580 200 99 Confidence Level 200 mV 199 990 0 1 10 90 80 140 80 140 80 200 80 210 80 10 40 90 25 140 25 140 25 145 25 160 25 40 100 70 25 115 25 115 25 125 25 135 25 100 2 k 4...

Страница 22: ...DC 60 Hz Crest Factor 200 mV to 200 V ranges 10 1 at 12 range 5 1 at 50 range 2 5 1 at full range 1000 V range 10 1 at 25 range 5 1 at full range Protection All ranges 1 kV rms Input Impedance 1 MΩ in parallel with 150 pF DC Accuracy DC Coupled Add 50 ppm Reading 50 ppm Range 20 μV Ratio Accuracy Range to Range Net Front Input Accuracy Net Rear Input Accuracy Within Range Apply 24 hour or 20 minut...

Страница 23: ...100 600 100 600 100 620 100 2 k 10 k 600 100 700 100 700 100 710 100 735 100 10 k 30 k 0 25 100 0 3 100 0 3 100 0 3 100 0 3 100 20 A 19 999 00 10 2 k 700 100 800 100 800 100 800 100 820 100 2 k 10 k 0 2 100 0 25 100 0 25 100 0 25 100 0 25 100 99 Confidence Level 199 990 0 1 10 250 120 300 120 300 120 590 120 620 120 10 10 k 250 120 300 120 300 120 590 120 620 120 10 k 30 k 600 120 700 120 700 120 ...

Страница 24: ... 2 1 3 10 10 k 15 20 10 k 30 k 15 20 2 A 10 2 k 10 15 0 3 0 4 2 k 10 k 15 20 10 k 30 k 20 30 20 A 10 2 k 20 25 0 04 2 k 10 k 25 30 Type True rms AC coupled DC coupled gives dc ac 2 2 Crest Factor 3 1 at 50 range 1 5 1 at full range Protection Front Input 20 A rms Rear Input 2 A rms Rear Panel Fuse Settling Time 200 μA to 200 mA Ranges 2 A Range 20 A Range at 10 A to 100 ppm of step to 100 ppm of s...

Страница 25: ...e 2 0 0 5 4 0 0 5 7 0 0 5 15 0 5 17 0 5 200 MΩ 199 990 000 High Voltage 3 5 5 0 6 0 5 0 9 0 5 0 60 5 0 65 5 0 2 GΩ 1 999 900 00 High Voltage 20 50 25 50 30 50 150 50 180 50 20 GΩ 19 999 000 0 High Voltage 250 500 350 500 500 500 525 500 1510 500 99 Confidence Level 2 Ω 1 999 900 00 Normal 6 0 2 5 10 2 5 12 2 5 19 2 5 22 2 5 20 Ω 19 999 000 0 Normal 3 0 0 9 5 5 0 9 8 5 0 9 11 5 0 9 12 0 0 9 200 Ω 1...

Страница 26: ... 0 6 1 0 20 kΩ 10 μA 0 8 0 7 0 6 1 0 200 kΩ 10 μA 0 5 0 5 0 6 1 0 2 MΩ 1 μA 2 0 0 5 2 3 20 MΩ 100 nA 15 5 20 30 200 MΩ 10 nA 200 500 200 300 2 GΩ 10 nA 200 500 200 300 Resistance High Voltage Mode Secondary Specifications 1 2 3 Temperature Coefficient 15 C 30 C 5 C 15 C 30 C 40 C Range 9 Measurement Current Transfer Uncertainty 20 mins 1 C ppm Reading ppm Range ppm Reading C 20 MΩ 10 μA 0 5 0 5 0 ...

Страница 27: ... 84 0 0025 100 Ω PRT SPRT 200 20 0 0040 100 Ω PRT SPRT 0 100 0 0025 100 Ω PRT SPRT 232 185 0 0020 200 1999 900 00 Ω 9 5 0 6 100 Ω PRT SPRT 400 250 0 0025 Temperature Readout Secondary Specifications 1 2 3 Resistance Measurement Uncertainty Temp Coeff ppm Reading C Resistance Range Transfer Uncertainty 20 Minute 1 C ppm Reading mΩ 11 2 Wire Adder Ω 3 Wire Adder Ω 15 C 30 C 5 C 15 C 30 C 40 C 0 199 ...

Страница 28: ... 5 Integration time 1 Power Line cycle 6 Valid for signals 1 Full Scale Transfer Mode On Signals must be DC coupled 40 Hz Readings invalid with Transfer Mode On and 1Hz filter selected when using internal trigger mode 7 Max Volt Hertz 3 x 107 8 300 V 10 kHz add 0 0004 x Reading 300 2 ppm 300 V 10 kHz 30 kHz add 0 0004 Frequency 10000 x10 7 x Reading 300 2 ppm 300 V 30 kHz add 0 0024 x Reading 300 ...

Страница 29: ...o elements are combined by adding algebraically For example measuring 10 V on the 20 VDC range and applying the 365 day 1 C specifications First expressing the contributions in terms of parts per million of the measured value V 10 of ppm 4 3 4 0 0 3 10 20 x 2 0 0 3 Second expressing the contributions in volts μV 34 10 x 4 3 20 x 10 x 2 0 10 x 10 x 0 3 5 6 6 The 8508 is designed to provide accuracy...

Страница 30: ... variations up to 5 C For applications where the knowledge of the effect of temperature on 8508A performance is important temperature coefficients are listed in the 8508A specifications If the operating temperature is within the range 15 C to 30 C the 15 C to 30 C temperature coefficient specifications are applicable otherwise use the 5 C to 15 C 30 C to 40 C figures provided the temperature lies ...

Страница 31: ...minute Transfer Uncertainty Specification for each value and combining the two specifications in an RSS summation expressing the contributions in parts per million of the measured values If the measurements are made within the same range but independently not using the ratio mode with an elapsed time greater than 20 minutes but less than 24 hours between the measurements then the 24 hour specifica...

Страница 32: ...8508A Service Manual 1 22 ...

Страница 33: ...2 1 Chapter 2 Theory of Operation Title Page Introduction 2 3 Overall Functional Description 2 3 Main Assemblies 2 3 Power Supplies 2 6 ...

Страница 34: ...8508A Service Manual 2 2 ...

Страница 35: ...A3 Ohms PCA Resistance measurements 2 wire 4 wire high voltage ratio etc A4 Digital PCA Out guard power supplies control of IEEE GPIB and serial data measurement and control A5 Bezel Assembly Front panel user interface display and keyboard includes the A5A1 Display PCA A6 Rear Input Assembly optional Rear input connections includes the A6A1 Rear Input PCA Normal operator interaction with the Multi...

Страница 36: ...I DC and I AC AC AC DC Input Signal Switching Relays Out Guard Power Supply 5 V 8 V 17 V Line Power A1 DC PCA A2 AC PCA A3 Ohms PCA A4 Digital PCA Input Select Input Select Input Select Input Select 2 Wire 4 Wire Range 15 V I to R Converter Rectifier RMS Converter DC AMP Chopper Stabilized AD MUX Internal Reference In guard Out guard In guard Power Supplies 250 VAC 5 V 8 V 15 V 36 V Lo Pass Filter...

Страница 37: ...ternal signal bus for measurement and display These tests provide a high degree of certainty that the Multimeter is functioning correctly and they are useful for troubleshooting to the board level The A2 AC PCA performs the ac voltage and ac current measurements The ac voltage portion of the assembly includes an associated collection of range configutation and filter circuits as well as an ac prea...

Страница 38: ...splay and keyboard and the opto couplers on the A1 DC PCA The in guard supplies provide power for the analog measurement side of the Multimeter This includes the A1 DC PCA the A2 AC PCA and the A3 Ohms PCA Two chassis mounted transformers T1 and T2 are the source of all the various voltages required for operation of the Multimeter See Figure 2 2 Transformer T2 is the fused line powered mains trans...

Страница 39: ...V regulator 5 V regulator T2 F1 T1 17 V J502 J501 15 V dc 5 V dc 15 V regulator 15 V regulator 15 V dc 8 V dc 18 V dc 36 V dc In guard Voltages Out guard Voltages 36 V dc 250 V ac to Ohms PCA 36 V regulator 36 V regulator 5 V regulator J401 J150 avw004f eps Figure 2 2 Power Supplies Simplified Block Diagram ...

Страница 40: ...8508A Service Manual 2 8 ...

Страница 41: ...n 3 7 SPCL Menu 3 7 SER Menu 3 7 Hvlin Menu 3 8 Non volatile input offset compensation 3 8 Routine Calibration 3 9 Equipment Required for Calibration 3 10 Preparing for Calibration 3 10 Interconnections 3 11 ADC Calibration 3 14 DC Voltage Calibration 3 14 AC Voltage Calibration 3 16 Resistance Calibration 3 18 DC Current Calibration 3 25 AC Current Calibration 3 27 Frequency Calibration 3 28 Exit...

Страница 42: ...anual 3 2 Applicable Verification Tolerance and Conditions 3 32 Preparation 3 33 DC Voltage Checks 3 33 AC Voltage Checks 3 35 Resistance Checks 3 37 DC Current Checks 3 40 AC Current Checks 3 41 Frequency Checks 3 43 ...

Страница 43: ...ate a single range or single point if the user chooses to do so However it is recommended that the calibration procedure listed later in this chapter be followed closely Calibration Interval and Performance It is recommended that the Multimeter be calibrated on either a 365 day or 90 day interval depending on the requirements of the applications for which the Multimeter is used and the performance...

Страница 44: ...ode Pressing the CAL key on the front panel causes the Multimeter to respond as follows 1 Enters the calibration CAL mode 2 Displays and allows access to the CALIBRATION menu 3 Displays the CAL legend on the main display To exit the CALIBRATION menu Press the Quit softkey On exit the Multimeter displays the prompt to enter a calibration due date When in CAL mode the following front panel keys beco...

Страница 45: ...er and entry to other calibration utilities Quit Exits from the CALIBRATION menu via the CALIBRATION DUE menu where the recommended next calibration date can be entered before finally quitting the calibration mode SET VALUE Menu This menu is obtained by pressing the Set key in the CALIBRATION menu on all functions except ACV Spot Frequency adj139f eps SET VALUE Menu When this menu appears it shows...

Страница 46: ...al point value is displayed and the keyboard is activated A numeric value can be entered that represents the RMS value of the calibration source signal adj141f eps SPOT n RMS Menus Enter Stores the displayed RMS value and de activates the keyboard The dot matrix display moves to the SPOT FREQUENCY 1 to 6 menu showing the calibration signal frequency Quit Reverts to the SPOT CAL menu not storing an...

Страница 47: ...main display When in Special CAL mode the following front panel keys remain inoperative CLEAR TEST OFFSET PRT and INPUT Also the function of the SAMPLE key changes to become the trigger key for initiating the Hvlin calibration operation adj137f eps SPCL Menu The SPCL menu provides the selection Ser Permits entry of the Multimeter s serial number Adc Aligns the different resolutions available from ...

Страница 48: ... correction factor at the end of the sequence PREV Moves back to the previous menu allowing the user to repeat the previous step in the sequence if required NEXT Moves forward through the sequence to the next step and signal level CALC Initiates calculation and storage of the high voltage linearity correction factor completing the Hvlin calibration process Non volatile input offset compensation Go...

Страница 49: ...urement practice 2 Users will take precautions to avoid introducing errors from sources such as thermal emfs leakages electromagnetic interference etc 3 Users will make adequate allowance for equipment stabilization and measurement settling times This routine calibration procedure describes the calibration points and sequence of operations required to calibrate the Multimeter and assumes calibrati...

Страница 50: ...hermal emf 4 wire shorting devices and connecting leads Fluke 8508A 7000K PC Network Printer Cables PC Network Printer Cables Any Metrology bd software Fluke MetBase Metrology Calibration Software Fluke Metcal v6 11 or later 1 Availability of a 1 MHz frequency reference signal may be required for 5720A frequency locking during 8508A frequency calibration procedure 2 Best uncertainties are obtained...

Страница 51: ... key when a calibration operation is intended to be performed Table 3 2 Calibration Sequence General Sequence for Full Multimeter Calibration 1 Enable Calibration Enter Cal mode Set rear panel calibration switch to ENABLE Access CALIBRATION menu Adc Cal Analog to digital converter alignment Performed only if required DCV Range Zeros and Range Gains 200 mV to 1 kV Ranges ACV Range Zeros Range LF Ga...

Страница 52: ... Fluke 8508A 7000K Calibration kit plugs directly into the Multimeter s front input terminals without any interconnecting leads If alternate resistance standards are used for resistance calibration refer to the resistance measurements section of Chapter 3 Making Measurements for connection details The Fluke 8508A 7000K Calibration kit also contains two precision low thermal emf 4 wire shorting dev...

Страница 53: ...TPUT HI LO 8508AREFERENCE MULTIMETER 8508A 7000K PM 8508A 7000K 4 W SHORT 4 10590 A Link guard and ground terminal Link guard and ground terminal Red Red Black Blue Green White Red Red Black Blue Green White White Green adj381f eps Figure 3 1 Equipment Connections Required for Calibration ...

Страница 54: ...alibration operation which will take approximately 3 minutes to complete Calibration is complete when the Busy legend goes out DC Voltage Calibration XW Warning The Calibrator can deliver a lethal electric shock To avoid electric shock when performing the following calibration procedures Never touch any lead or terminal unless you are absolutely certain that no dangerous voltage is present Make su...

Страница 55: ...Gain ve 1000 V The procedure assumes the user has knowledge of the actual output value of the calibrator at the range gain values from a measurement or from a certificate of calibration The Set feature allows a user to enter the true output value of the calibration standard where it differs from the nominal range gain point If the calibrator output is considered to be exactly nominal use of the Se...

Страница 56: ...resent Make sure that signal leads are in a safe condition before you handle them in any way Initial Setup and Connections 1 Press the ACV key select the 200 mV range 2 Press the CONFIG key In calibration mode in the ACV function Transfer mode defaults to On for enhanced performance resolution defaults to RESL6 and the 100Hz RMS filter is automatically selected It is recommended that this resoluti...

Страница 57: ...he Set feature allows a user to enter the true output value of the calibration standard where it differs from the nominal point If the calibrator output is considered to be exactly nominal use of the Set feature is not required also omit steps 3 5 On each range the Multimeter automatically recognizes the appropriate value as range zero from the applied signal amplitude and automatically recognizes...

Страница 58: ...ence Table 3 5 Resistance Calibration Points and Sequence 8508A Range Modes Point Resistance Zero 0 Ω 2 Ω Normal Normal LoI TruΩ TruΩ LoI Range Gain 1 Ω Zero 0 Ω 20 Ω Normal Normal LoI TruΩ TruΩ LoI Range Gain 10 Ω Zero 0 Ω 200 Ω Normal Normal LoI TruΩ TruΩ LoI Range Gain 100 Ω Zero 0 Ω 2 kΩ Normal Normal LoI TruΩ TruΩ LoI Range Gain 1 kΩ Zero 0 Ω 20 kΩ Normal Normal LoI TruΩ TruΩ LoI Range Gain 1...

Страница 59: ... in Table 3 5 for the NormalΩ mode For the 2 GΩ range use the 1 GΩ standard resistor in place of the calibrator Just one range can be calibrated if required but for a full calibration start with the 2 Ω range and work up to the 2 GΩ range Note that EX SNS 4 wire is not available on the 5720A 100 MΩ range and the 8508 7000K 1 GΩ standard resistor is used as a 2 wire device with the calibrator 2 wir...

Страница 60: ... 2 Press the CONFIG key and select Filt LoI and 4wΩ Range Zero and Gain Calibration Procedure After the initial setup and connecting up use the following procedure to calibrate range zero and range gain for the ranges and points detailed in Table 3 5 for the LoI mode For the 2 GΩ range use the 1 GΩ standard resistor in place of the calibrator Just one range can be calibrated if required but for a ...

Страница 61: ...in the true output value of the calibrator or the value of the resistance standard at the range gain value then press Enter 5 Press SAMPLE Calibration is complete when the Busy legend goes out and the calibrated measurement is displayed 6 On the Calibrator set STANDBY 7 Press the Ω key to revert to the ranges menu TruΩ Mode Calibration 1 Press the Ω Plus key and select TruΩ From the TruΩ menu sele...

Страница 62: ...libration is complete when the Busy legend goes out and the calibrated measurement is displayed 6 On the Calibrator set STANDBY 7 Press the Ω key to revert to the ranges menu TruΩ LoI Mode Calibration 1 Press the Ω Plus key and select TruΩ From the TruΩ menu select the 2Ω range 2 Press the CONFIG key and select Filt LoI and 4wΩ Range Zero and Gain Calibration Procedure After the initial setup and ...

Страница 63: ...to initiate the calibration operation Calibration is complete when the Busy legend goes out and the calibrated measurement is displayed 6 On the Calibrator set STANDBY 7 Press the Ω key to revert to the ranges menu HiVΩ Mode Calibration XW Warning The Multimeter can deliver a lethal electric shock when operating in the High Voltage Resistance mode Voltages up to 240V may appear on the terminals To...

Страница 64: ... a user to enter the true output value of the calibration standard where it differs from nominal range gain point If the resistance value is exactly the nominal value required omit steps 2 4 for the Range Gain Point Zero Point 1 On the Multimeter select the required range 2 On the Calibrator select zero Ω and Operate For the 200 MΩ range and above de select Ex SNS on the calibrator and de select 4...

Страница 65: ...range 2 Press the CONFIG key Select Filt 3 In calibration mode the resolution defaults to RESL7 in the DCI function It is recommended that this resolution is used for calibration of all DCI ranges 4 Reselect DCI 5 Confirm that the Multimeter is configured for internal guard External Guard is deselected by checking that the Ext Grd legend does not appear on the left hand display 6 Ensure that the c...

Страница 66: ...rtificate of calibration The Set feature allows a user to enter the true output value of the calibration standard where it differs from the nominal range gain point If the calibrator output is considered to be exactly nominal use of the Set feature is not required also omit steps 2 4 for the Range Gain Points On each range the Multimeter automatically recognizes the appropriate value as range zero...

Страница 67: ...inal unless you are absolutely certain that no dangerous voltage is present Make sure that signal leads are in a safe condition before you handle them in any way Initial Setup and Connections 1 Press the ACI key and select the 200μA range 2 Press the CONFIG key In calibration mode in the ACI function resolution defaults to RESL6 and the 100Hz RMS filter is automatically selected It is recommended ...

Страница 68: ...ltimeter select the required Range 2 On the Calibrator select Output Current and Frequency Operate 3 On the Multimeter Press CAL to revert to CALIBRATION menu 4 Select Set on the CALIBRATION menu 5 Use the numeric keys with the SET VALUE menu to key in the true output value of the calibrator then press Enter 6 Press SAMPLE to initiate the calibration operation Calibration is complete when the Busy...

Страница 69: ...ation operation Calibration is complete when the Busy legend goes out 4 On the Calibrator set STANDBY Exit From Calibration Mode and Non Volatile Input Offset Adjustment Use the following procedure to perform non volatile input offset adjustment on all DCV and resistance ranges including LoI 2 wire and 4 wire for the front and rear inputs Initial Setup and Connections 1 Press the CAL key and selec...

Страница 70: ...imeter It is also recommended that a calibration seal or integrity sticker is applied to prevent unauthorized access to the rear panel calibration enable switch Set Cal Due Date 1 Press the CAL key and select Quit 2 From the CAL DUE menu select Enter 3 Use the keypad to key in the calibration due date Up to eight characters may be entered in any format Any character available from the keypad may b...

Страница 71: ...rement is displayed The menu display reverts to the SPOT CAL menu 8 On the Calibrator set STANDBY 9 On the Multimeter select other spots as required repeating the process for each selection 10 Exit from the SPOT CAL menu by pressing any hard key Performance Verification The 8508A Digital Reference Multimeter offers state of the art performance This procedure is intended as a guide for qualified me...

Страница 72: ...ing Measurements for connection details Applicable Verification Tolerance and Conditions The tolerances listed in this verification procedure are derived from the Multimeter s 365 day Tcal 1 C 99 Confidence Level Absolute specifications which include contributions for the performance of the Multimeter itself and the uncertainty of the calibration standards used to perform calibration adjustment of...

Страница 73: ...uration 1 Ensure that the calibrator output is set to STANDBY and configured for Internal Guard EXT GRD is deselected 2 Connect the equipment as described for Routine Calibration 3 Press the DCV key 4 Press the CONFIG key Select Filt and RESL7 5 Confirm that the Multimeter is configured for internal guard External Guard is deselected by checking that the Ext Grd legend does not appear on the left ...

Страница 74: ...eration to calibrator range locked zero output 100 mV 0 00072 mV 200 mV 100 mV 0 00072 mV 0 V Perform input zero operation to calibrator range locked zero output 1 V 0 0000045 V 2 V 1 V 0 0000045 V 0 V Perform input zero operation to calibrator range locked zero output 1 V 0 000009 V 10 V 0 000045 V 19 V 0 000081 V 1 V 0 000009 V 10 V 0 000045 V 20 V 19 V 0 000081 V 0 V Perform input zero operatio...

Страница 75: ... internal guard External Guard is deselected by checking that the Ext Grd legend does not appear on the left hand display Procedure Repeat the following sequence for each range starting with the 200mV range and working up to the 1kV range as listed in Table 3 9 1 Select the required range on the multimeter 2 On the Multimeter press CONFIG and select the appropriate filter for the point being verif...

Страница 76: ...44 V 1 V 55 Hz 40 Hz 0 000119 V 1 V 1 kHz 100 Hz 0 000099 V 1 V 3 kHz 100 Hz 0 000119 V 1 V 10 kHz 100 Hz 0 000119 V 1 V 30 kHz 100 Hz 0 000295 V 1 V 60 kHz 100 Hz 0 000795 V 1 V 100 kHz 100 Hz 0 000795 V 1 V 500 kHz 100 Hz 0 034000 V 2 V 1 V 1 MHz 100 Hz 0 034000 V 1 V 1 kHz 100 Hz 0 00032 V 10 V 20 Hz 10 Hz 0 00144 V 10 V 55 Hz 40 Hz 0 00099 V 10 V 1 kHz 100 Hz 0 00119 V 10 V 3 kHz 100 Hz 0 0011...

Страница 77: ...s When verifying the resistance function each of the resistance modes NormalΩ TruΩ LoIΩ and HiVΩ must be individually checked The following procedure assumes use of a multifunction calibrator and verifies each resistance mode in turn range by range If individual standard resistors are used it may be more convenient to check all the modes in turn for each resistance value to avoid connecting the sa...

Страница 78: ...dures Never touch any lead or terminal unless you are absolutely certain that no dangerous voltage is present Make sure that signal leads are in a safe condition before you handle them in any way 1 Press the Ω key 2 Press the CONFIG key and select Filt RESL7 and 4wΩ Ensure LoI is deselected 3 Select the required Multimeter range 4 On the Calibrator select zero Ω and Operate Alternatively if using ...

Страница 79: ...ed zero output 2 Ω 1 Ω 0 0000240 Ω 0 0000240 Ω 0 Ω Perform input zero operation to calibrator range locked zero output 20 Ω 10 Ω 0 000133 Ω 0 000133 Ω 0 Ω Perform input zero operation to calibrator range locked zero output 200 Ω 100 Ω 0 00101 Ω 0 00113 Ω 0 kΩ Perform input zero operation to calibrator range locked zero output 2 kΩ 1 kΩ 0 0000101 kΩ 0 0000113 kΩ 0 kΩ Perform input zero operation to...

Страница 80: ... described for Routine Calibration 3 Press the DCI key 4 Press the CONFIG key Select Filt and RESL7 5 Confirm that the Multimeter is configured for internal guard External Guard is deselected by checking that the Ext Grd legend does not appear on the left hand display Procedure Repeat the following sequence for each range starting with the 200μA range and working up to the 20A range as listed in T...

Страница 81: ... operation to calibrator range locked zero output 100mA 0 00530 mA 200 mA 100mA 0 00530 mA 0 A Perform input zero operation to calibrator range locked zero output 1A 0 0002260 A 2 A 1A 0 0002260 A 0 A Perform input zero operation to calibrator range locked zero output 10A 0 004950 A 20 A 10A 0 004950 A 1 Based on 365 day Tcal 1 C 99 CL Absolute specifications See comments in Applicable Verificatio...

Страница 82: ...08A Range Current Frequency Tolerance 1 100 μA 300 Hz 0 0830 μA 100 μA 1 kHz 0 0830 μA 100 μA 3 kHz 0 0830 μA 100 μA 5 kHz 0 0830 μA 200 μA 100 μA 10 kHz 0 0830 μA 1 mA 300 Hz 0 000580 mA 1 mA 1 kHz 0 000580 mA 1 mA 3 kHz 0 000580 mA 1 mA 5 kHz 0 000580 mA 2 mA 1 mA 10 kHz 0 000580 mA 10 mA 300 Hz 0 00580 mA 10 mA 1 kHz 0 00580 mA 10 mA 3 kHz 0 00580 mA 10 mA 5 kHz 0 00580 mA 20 mA 10 mA 10 kHz 0 ...

Страница 83: ...08A is configured for internal guard External Guard is deselected by checking that the Ext Grd legend does not appear on the left hand display Procedure 1 On the 8508A press MONITOR and then CONFIG Deselect FREQ GATE Fast 2 Press the MONITOR key and select FREQ 3 On the calibrator set the output to the voltage to 1V and frequency to 1MHz Set the output to OPERATE 4 Note the Multimeter s frequency ...

Страница 84: ...8508A Service Manual 3 44 ...

Страница 85: ...r handling them 3 Using the procedures packaging and bench techniques that are recommended The following practices should be followed to minimize damage to S S static sensitive devices 1 MINIMIZE HANDLING 2 KEEP PARTS IN ORIGINAL CONTAINERS UNTIL READY FOR USE 3 DISCHARGE PERSONAL STATIC BEFORE HANDLING DEVICES USE A HIGH RESIS TANCE GROUNDING WRIST STRAP 4 HANDLE S S DEVICES BY THE BODY static aw...

Страница 86: ...VE EDGES AND NEVER TOUCH OPEN EDGE CONNECTOR EXCEPT AT STATIC FREE WORK STATION PLACING SHORTING STRIPS ON EDGE CONNECTOR HELPS PROTECT INSTALLED S S DEVICES 9 HANDLE S S DEVICES ONLY AT A STATIC FREE WORK STATION 10 ONLY ANTI STATIC TYPE SOLDER SUCKERS SHOULD BE USED 11 ONLY GROUNDED TIP SOLDERING IRONS SHOULD BE USED PORTIONS REPRINTED WITH PERMISSION FROM TEKTRONIX INC AND GERNER DYNAMICS POMON...

Страница 87: ...ms PCA 4 7 Removing the A4 Digital PCA 4 8 Removing the A5 Bezel Assembly 4 9 Removing the A5A1 Display PCA 4 10 Removing the A6 Rear Input Assembly 4 11 Fuse Replacement and Line Voltage Selection 4 12 Line Power Fuse F1 and Voltage Selection 4 12 Rear Input Current Fuse F2 Rear Inputs Option 4 13 Self Test 4 13 Self Test Errors 4 13 Fatal Errors 4 16 Execution Errors 4 18 Device Dependant Errors...

Страница 88: ...8508A Service Manual 4 2 ...

Страница 89: ...your safety and for the protection of the Multimeter follow all of the considerations and recommendations that follow 1 Unless you are qualified to service the the Multimeter do not remove the covers from the unit 2 To avoid shock hazards and for the protection of the unit disconnect all power cords rear panel cables and front rear test leads from the Multimeter 3 Be aware that removing either or ...

Страница 90: ...CA A4 Digital PCA A3 Ohms PCA J202 J201 J122 J121 J120 J132 J130 J112 J113 J110 J111 J109 J801 WHT BLU BRN BLK RED GRN J15 J152 J153 J151 J801 J154 J401 J202 J201 T2 3 10 W6 16 W5 16 4 4 4 T1 Power Input and Voltage Selection Module J302 J301 J501 J502 PL30 PL31 PL32 E101 E102 E103 E104 E105 E106 Yellow Orange Green Red Brown Black J301 J401 W3 16 W2 16 W4 26 SENSE INPUT HI LO HI LO A GUARD A5A1 A...

Страница 91: ...rd the back of the unit and lift it off 4 Remove the bottom shield C a Remove the six philips screws from the shield b Slide the shield toward front of unit and lift it out 5 Remove the A1 DC PCA D a Disconnect the Rear Input PCA from the A1 DC PCA b Disconnect the five connectors from the rear edge of the A1 DC PCA c Disconnect the 10 connectors from the front edge of the A1 DC PCA d Disconnect t...

Страница 92: ...and lift it off 4 Remove the top shield C a Remove the four philips screws from the shield D b Slide the shield toward front of unit and lift it out 5 Remove the A2 AC PCA E a Remove the eight philips screws holding the shield to the A2 AC PCA b Lift the shield from the PCA c Disconnect the one connectors from the rear edge of the A2 AC PCA d Disconnect the three connectors from the front edge of ...

Страница 93: ...e yellow and the black brown wires 5 Disconnect both connectors from the A1 DC PCA These cables are hardwired to the A3 Ohms PCA and must be disconnected before the A3 Ohms PCA can be removed 6 Position the unit on the work surface so it is top side up 7 Remove the top shield C a Remove the four philips screws from the shield b Slide the shield toward front of unit and lift it out 8 Remove the A3 ...

Страница 94: ... off 4 Remove the Rear Panel D a Remove the six flat head philips screws from the rear panel two on either side of the panel and two with the input sense connector group b Remove the seven pan head philips screws distributed across the rear panel c Pull the gray sheet metal portion of the rear panel away from the unit 5 Set the unit on its side and remove the screw holding the input sense connecto...

Страница 95: ...ft it out 5 Locate the five connectors J109 through J113 on the A1 DC PCA with the green and white blue brown red and black wires When reassembling the unit make sure you reconnect the connectors in the left to right color sequence described in this step 6 Disconnect all five connectors from the A1 DC PCA These cables are hardwired to the A5 Bezel Assembly and must be disconnected before the A5 Be...

Страница 96: ...lips screws holding the A5A1 Display PCA to the plastic bezel front panel A 3 Lift the top of the A5A1 Display PCA until it clears the lip of the bezel and then pull the A5A1 Display PCA toward the lip of the plastic bezel B Before reassembling the A5 Bezel Assembly check the position of the rubber key pads to ensure that all of the buttons are correctly seated in their holes C 3 1 2 avw015f eps F...

Страница 97: ...nse connector group b Remove the seven pan head philips screws distributed across the rear panel c Pull the gray sheet metal portion of the rear panel away from the unit 5 Remove the bottom shield E a Remove the six philips screws from the shield b Slide the shield toward front of unit and lift it out 6 Locate and remove the screw holding the input sense connector group to the chassis F 7 Cut the ...

Страница 98: ... 115 or 230 The fuse rating is a function of the selected line voltage as shown in Table 4 1 Use the following procedure to change the fuse or change the line power selection 1 Remove the fuse tray by placeing a small screwdriver blade under the tab on the fuse tray and pulling the tray from the module 2 To change the voltage selection rotate and position the fuse holder in the tray so the desired...

Страница 99: ... is identified by the presence or absence of the id column in the error code table The error codes are classified as Self Test Errors Fatal Errors Execution Errors and Device Dependant Errors All error conditions other than Fatal Errors are recoverable For help in determining what to do in the event of a self test error make a note of the full error message and contact your nearest Fluke Service C...

Страница 100: ...ck Test No 49 Err 2491 P041 1A DC Range 100mA Input Gain Check AC CURRENT Test No 50 Err 2501 P042 1mA AC Range Zero Input Check Test No 51 Err 2511 P043 1mA AC Range 1mA Input Gain Check RESISTANCE Test No 60 Err 2601 P044 Follower Offset Check Test No 61 Err 2611 P045 Follower 100mA Output Check Test No 62 Err 2621 P046 Follower 10mA Output Check Test No 63 Err 2631 P047 Follower 1mA Output Chec...

Страница 101: ...put Test No 87 Err 2871 P022 1V AC Range 993mV DC Input Checks at RMS Converter Output Test No 88 Err 2881 2882 raw P023 10V AC Range Zero Input Check Test No 89 Err 2891 P024 10V AC Range 9 78V DC Input Checks at PreAmp Output Test No 90 Err 2901 P025 10V AC Range 9 78V DC Input Checks at PreAmp Output Test No 91 Err 2911 2912 raw P026 100V AC Range Zero Input Check Test No 92 Err 2921 P027 100V ...

Страница 102: ... Kernel Fault Errors id Fault 00 user stack overwritten addr user stack pointer address 01 activity at head of queue not current addr address of queue 02 current activity not at head of queue addr address of queue 9001 Run Time System Error This error is detected and generated by the Pascal run time system support e g variable out of range 9002 Unexpected Exception Addr id See Table 4 5 for descri...

Страница 103: ...ence on all transfers Can be because serial data coming from the analog subsystem to the digital ULA is corrupt Could also be a serial clock or enable problem 04 In Guard Error Indicates in_guard circuit latches corrupted and new update required Reported as fail after 20 consecutive errors This signal may be polled during updates otherwise it causes an interrupt 05 State Change Timeout Interface s...

Страница 104: ...ch should be 11111011 9007 Unknown Engine Instruction Addr id id indicates the code that the engine was attempting to interpret as an instruction Execution Errors An Execution Error is generated if a received command cannot be executed because it is incompatible with the current device state or because it attempts to command parameters which are out of limits In remote operation the EXE bit 4 is s...

Страница 105: ...rnal operating fault e g during self test The DDE bit 3 is set true in the Standard defined Event Status Byte and the error code number is appended to the Device Dependent Error queue In remote mode operations the error is associated with status reporting and the queue entries can be read destructively as LIFO by the Common query command DDQ In local mode operations the DDE status is checked at th...

Страница 106: ...o 1 of full range 2006 Error During LoI Gain Cal The input signal was outside full range 10 of full range 2008 Error During A to D Cal error numbers between 2030 and 2089 see section 2 2010 Error During Frequency Cal 2012 Error During DCcp Cal 2025 Error During HiV Lin Read 2026 Error During HiV Lin Calc 2027 Error During 2wr Ohms Calc Corruptions 2014 Serial Number Corrupt 2015 Cal Due Date Corru...

Страница 107: ...5 1 Chapter 5 List of Replaceable Parts Title Page Introduction 5 3 How to Obtain Parts 5 3 How to Contact Fluke 5 3 Parts Lists 5 4 ...

Страница 108: ...8508A Service Manual 5 2 ...

Страница 109: ...t number under the heading FLUKE STOCK NO To order components directly from Fluke Corporation call toll free 800 526 4731 Parts price information is available from the Fluke Corporation or its representatives To ensure prompt delivery of the correct part include the following information when you place an order Fluke stock number Description as given under the Description heading Quantity Referenc...

Страница 110: ...2398145 2 MP4 Bumper Foot Self Adhesive 2398373 4 MP5 Foot Rear 1628388 2 MP6 Bottom Foot Moulded 868786 4 MP7 Bail Tilt Stand 1988619 2 MP8 Label Calibration Sticker 2398123 3 MP9 Label Barcode ModelL Serial Number 2398138 1 MP10 Label Modification Record 2398114 1 H1 Washer M4 Crinkle SS GKN 2398274 6 H2 Screw 8 32 X 3 8 SH SKTHD Black 295105 6 H3 Screw M3 X 8 Pozipan 2398200 2 WF1 Fuse 630 mA 2...

Страница 111: ...List of Replaceable Parts Parts Lists 5 5 5 2 2 2 6 6 2 3 4 MP1 MP2 MP5 MP7 MP9 MP10 H3 H1 H2 MP3 MP4 4 MP6 MP8 avw025 eps Figure 5 1 8508A Final Assembly ...

Страница 112: ...INT SHAKP SZP 2398263 1 H9 Nut Full 1 4 28 UNF BNP 2398301 1 H10 Nut Nylock M4 SZP 2398295 4 H11 Washer M4 Plain SZP 2398242 4 H12 Screw M3 X 6 Pozicsk 2398189 22 H13 Standoff M3 X 16 M F Nylon 2398221 4 H14 Screw M3 X 8 Pozicsk 2398192 6 MP1 PCB Card Guide 2398312 2 MP3 Bush Insulating 8 8 ID Black 2398347 1 MP2 Hole Plug 5 8 Black 2398358 7 1 T1 Low Voltage Transformer Assembly 2398036 1 T2 Main...

Страница 113: ...of Replaceable Parts Parts Lists 5 5 7 8 4 6 10 STICK OVER SMALL HOLES MP4 W2 MP3 DC PCA AC PCA Ohms PCA Top View Bottom view H12 H13 H2 A2 A4 W4 A1 H12 10 2 H5 avw026f eps Figure 5 2 8508A Chassis Assembly ...

Страница 114: ...8 2 A5 WHITE GREEN BROWN RED BLACK BLUE A401 DC PCA Bottom view W5 W6 A401 H1 4 FORM RIBBON CABLES AS SHOWN AND CONNECT TO CONNECTORS ON REAR OF DISPLAY BOARD W1 H2 A1 T1 T2 avw027f eps Figure 5 2 8508A Chassis Assembly cont ...

Страница 115: ...able Parts Parts Lists 5 5 9 T2 2 H11 2 H3 2 H6 2 MP1 7 7 NOT REQUIRED IF REAR INPUT FITTED A4 Digital PCA T2 H9 H8 H14 H7 H6 W7 H10 H4 H7 H5 2 T1 H11 H10 2 MP2 H2 W3 avw028 eps Figure 5 2 8508A Chassis Assembly cont ...

Страница 116: ...17 7 H3 Washer M3 Int SHAKP SZP 2398239 1 H4 Washer M4 Int SHAKP SZP 2398256 6 H5 Washer Terminal 859939 1 H6 Nut Full M3 SZP 2398288 1 H7 Nut Terminal 8 32 UNC 850334 12 J1 J2 J3 Terminal Low Thermal Red 886382 3 J4 J5 Terminal Low Thermal Black 886379 2 J6 Terminal Low Thermal Blue 886366 1 L1 Ferrite Core 8680 nH 2398386 1 MP2 Front Handle 1605343 2 MP3 Display Lens 1607661 1 MP5 Keypad Set 160...

Страница 117: ...5 ALL WIRES EXCEPT GREEN LOOP ONCE THROUGH FERRITE RED RED RED BLU BLK BLK GREEN WIRE RED WIRE PINK WIRE BROWN WIRE BLUE WIRE WHITE WIRE BLACK WIRES FIT THIN WIRE UNDER THICK WIRE NOTE POSITION CAPACITOR AWAY FROM OTHER TERMINALS MP3 L1 H3 H6 C2 C1 W1 H1 A1 avw029f eps Figure 5 3 A5 Bezel front panel Assembly ...

Страница 118: ...12 H4 Washer Terminal 859939 6 H5 Washer Terminal Large 613606 6 H6 Washer M3 Int Shakp SZP 2398239 1 H7 Nut Full M3 SZP 2398288 1 H8 Screw M3 x 6 POSICSK SZP 2398189 2 H9 Tie Cable 2 5 x 115 mm 2398177 3 H10 Tie Holder 2398335 1 H11 Screw M3 x 8 POZIPAN SEMS 2398200 1 H12 Circuit Board Support 2398364 3 H13 Terminal Insulator 894183 6 H14 Terminal Base 885459 6 J2 J4 Terminal Low Thermal Black 88...

Страница 119: ... GREEN H9 H10 FH1 ORANGE WIRE ORANGE WIRE F1 RED WIRE BROWN WIRE WHITE WIRE BLUE WIRE BLACK WIRE GREEN WIRE H14 H3 W1 6 12 H2 6 H4 6 H5 6 6 C1 C2 H8 H12 Red Black Blue 8 wires with terminals A1 L1 H11 L1 L1 H1 H7 H6 J1 J3 J5 J2 J4 J6 H13 avw030f eps Figure 5 4 Rear Input Assembly optional ...

Страница 120: ...8508A Service Manual 5 14 ...

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