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1. Test No 28 Err 2281 P011 10V Range Positive Gain Check Test No 29 Err 2291 P012 10V Range Negative Gain Check Test No 30 Err 2301 P013 100V Range Positive Gain Check Test No 31 Err 2311 P014 100V Range Negative Gain Check DC CURRENT Test No 40 Err 2401 P032 100uA DC Range Zero Input Check Test No 41 Err 2411 P033 100uA DC Range 100uA Input Gain Check Test No 42 Err 2421 P034 1mA DC Range Zero Input Check Test No 43 Err 2431 P035 1mA DC Range 1mA Input Gain Check Test No 44 Err 2441 P036 10mA DC Range Zero Input Check Test No 45 Err 2451 P037 10mA DC Range 10mA Input Gain Check Test No 46 Err 2461 P038 100mA DC Range Zero Input Check Test No 47 Err 2471 P039 100mA DC Range 100mA Input Gain Check Test No 48 Err 2481 P040 1A DC Range Zero Input Check 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 Check Test No 64 Err 2641 P048 3 0V Clamp Check Test No 65 Err 2651 P049 6 7V Clamp Check Test No 66 Err 2661 P050 27V Clamp Check Test No 67 Err 2671 P051 Current Sink Clamp Check Test No 68 Err 2681 P052 10uA Current Sink a
2. DC Current DC Current 7 Uncertainty Relative to Cal Stds Absolute Uncertainties Range Full Scale ppm Reading ppm Range 24 hour 90 day 365 day 365 day 365 day TCal 1 C TCal 1 C TCal 1 C TCal 1 C TCal 5 C 95 Confidence Level 200 pA 199 990 00 5 5 2 0 6 0 2 0 6 5 2 0 12 4 2 0 12 4 2 0 2 mA 1 999 900 0 5 5 2 0 6 0 2 0 6 5 2 0 1242 0 124 2 0 20 mA 19 999 000 6 5 2 0 7 0 2 0 8 0 2 0 1342 0 14 2 0 200 mA 199 990 00 28 4 0 30 4 0 33 4 0 36 4 0 48 4 0 2A 1 999 900 0 80 8 0 125 8 0 170 8 0 170 8 0 185 8 0 20A 19 999 000 200 20 290 20 380 20 380 20 400 20 99 Confidence Level 200 pA 199 990 00 7 0 2 0 7 5 4 2 0 8 0 2 0 1542 0 16 2 0 2mA 1 999 900 0 7 0 2 0 7 5 4 2 0 8 0 2 0 1542 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 2A 1 999 900 0 100 8 0 150 8 0 205 8 0 210 8 0 225 8 0 20A 19 999 000 250 20 350 20 450 20 455 20 500 20 DC Current Secondary Specifications 9 Temperature Coefficient Range Input Impedance Q JECC IMC 2 Front Rear ppm Reading C 200 uA 150 150 0 4 0 6 2mA 15 2 15 2 0 4 0 6 20 mA 1 8 1 9 1 2 1 8 200 mA 1 2 1 3 6 0 9 0 2A 0 3 0 4 8 0 12 20A 0 04 15 20 PYPE e Multi slope multi cycle A D Converter Protection Front INpU t pe 20 A r
3. 10 E101 COO oO 9 S 2 tg uy E12 GREEN WHITE BLUE BLACK ORANGE BROWN RED ORANGE WIRE GREEN WIRE WHITE WIRE BLUE WIRE BROWN WIRE avw030f eps Figure 5 4 Rear Input Assembly optional 8508A Service Manual
4. sss 14 12 Rear Input Current Fuse F2 Rear Inputs Option 4 13 Self LS PL 14 13 Self Test EEfOIS ei ren en ia un Hug lehren 14 13 Fatal Errors ass inkl ren 14 16 Execution Erfots a na iniIRH EE QURE UE E ERES 4 18 Device Dependant Errors eueeessessseenseenneenneennennnennnennnnnnnnnnnnnn essen nen 4 19 List of Replaceable Parts eere Inttoductlori sccssecetscads ceteehinshovdasnteosshasdzevadesnedeous eat ovasaavesnaesiaesuaeeaubeonseatevaarnuaees How to Obtain Parts ener enne nennen nennen How to Contact Fluke teste een et Pants ASUS canoe ee nee HIERO lee RES eine iii 8508A Service Manual List of Tables Table Title Page 3 1 Required Equipment for Calibration and Performance Verification 13 10 3 2 Calibration Sequence cesserit ENN enne ener enne nennen nennen 3 11 3 3 DC Voltage Calibration Points and Sequence unnenesnesnnennnnennnnnne ne 3 15 3 4 AC Voltage Calibration Points and Sequence uunenennnsnnsnnnnnenneenne ne 13 17 3 5 Resistance Calibration Points and Sequence nnssenseeneneennnennnnennenne ne 3 18 3 6 DC Current Calibration Points and Sequence unncsenneneneennneenneennnenne ne 13 26 3 7 AC Current Calibration Points and Sequence uunsnnsennseeneeneesnnenneennneneenne nn 13 28 3 8 DC Voltage Verification Points and Sequence
5. Figure 4 5 Removing the A4 Digital PCA Maintenance 4 Access Procedures Removing the A5 Bezel Assembly Use the following procedure to remove the A5 Bezel Assembly See Figure 4 6 l 2 Position the unit on the work surface so it is bottom side up Remove both rear feet 1 a Remove the three hex screws from each foot b Ifthe feet are still in place pull them from the unit Remove the bottom cover 2 a Remove one philips screw at rear of the bottom cover b Slide the cover toward the back of the unit and lift it off Remove the bottom shield 3 a Remove the six philips screws from the shield b Slide the shield toward front of unit and lift it out 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 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 Bezel Assembly can be removed Remove the two hex screws from the side of each of the front handles 4 Thread the disconnected cables wires through the chassis opening and pull the A5 Bezel Assembly a few inches away from the unit 5 Free the A5 Bezel Assembly from the unit by disconnecting the two ribbon cables from the A5A1 Display PCA avw014f eps F
6. The equipment required for performance verification of the Multimeter 1s identical to the equipment required for routine calibration listed in Table 3 1 Alternate equipment may be used but users should ensure it provides adequate uncertainties and consider the impact of those uncertainties on allowable tolerance limits Interconnections The Fluke 8508A 7000K Calibration kit contains a specially designed lead set which connects directly to the terminals of the Multimeter the 5720A and the 57254 for the purpose of Multimeter calibration and performance verification It is recommended that this lead kit be used to avoid introducing measurement errors due to interconnections and to duplicate the configuration used by Fluke for Multimeter calibration A diagram showing the interconnections used in detail appears in the Routine Calibration section If alternate leads are substituted users must ensure they are metrology grade leads and of adequate voltage and current rating Leads should be kept as short as possible constructed from low capacitance low leakage dielectric material PTFE with low thermal emf terminations and exactly duplicate the configuration and interconnections shown When checking the 2 GQ and 20 GQ resistance ranges the 1 GQ standard resistor supplied in the Fluke 8508A 7000K Calibration kit plugs directly into the Multimeter s front input terminals without any interconnecting leads If alternate resistance standards are used
7. 3 8 Good metrology practice should ensure that all high precision measurements made with the Multimeter are preceded by an input zero of each measurement However a non volatile input offset compensation is independently available for the front and rear inputs and will be used whenever the input zero capability is not in use The compensation is retained after power down is unaffected by clearing the volatile input zeros and is unaffected by range zero calibration adjustments Compensation is available on all functions and includes separate compensation of 2 wire and 4 wire measurements in the resistance functions Calibration and Verification 3 Routine Calibration Non volatile input offset compensation adjustment is available only when the rear panel calibration keyswitch is in the ENABLE position and the CAL legend is not shown on the main display Adjustment is performed by initiating an input zero operation with the Multimeter in this condition using the INPUT menu as described in Chapter 3 or using the IEEE 488 input zeroing commands described in Chapter 4 Appy a high integrity low thermal emf 4 wire short to the input terminals for this operation Following adjustment for a particular combination of function range and input a compensation is also stored for the corresponding volatile input zero and the Zero legend is shown on the main display The Zero legend may be removed from the display without affecting the stored non volatil
8. 5 6 7 8 9 null zero was performed TCal Ambient calibration temperature Integration time 1 Power Line cycle Valid for signals gt 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 Max Volt Hertz 3 x 107 gt 300 V 10 kHz add 40 0004 x Reading 300 ppm gt 300 V 10 kHz 30 kHz add 0 0004 Frequency 10000 x107 x Reading 300 ppm gt 300 V gt 30 kHz add 40 0024 x Reading 300 ppm Typical below 10 Hz for ACV below 10 Hz and above 10 kHz for ACI and above 2 GQ for Resistance 10 Tru Ohms mode available on 2 Q to 20 kO ranges Read Rate reduced in Tru Ohms Mode Specification for Tru Ohms same as corresponding Normal or Lo Current range 11 Valid for 4 wire sensor 12 Not including sensor uncertainty 13 Assume Range and Full Scale 2000 V when calculating for 1000 V Range For DCI additional errors only apply in 5 digit resolution 14 Fast mode not available in PRT 15 The maximum display value for the Analog to Digital converter is 199 990 000 counts This sets the maximum value measurable on each range to be a one followed by four nines For example the maximum measured values on the 2 V range on DC Voltage are 1 999 900 00 V However the 1000 V ranges are limited to a maximum 1050 V Introduction and Specifications 1 Applying the Specifications Applying the Spec
9. C to 40 C Calibration TCal eene 20 C to 25 C Factory Cal Tem posisina 23 C Storage nr 20 C to 70 C Warm Up sense 4 hours to full uncertainty specification Relative Humidity non condensing Operating crier eiecit 5 C to 40 C lt 90 Storage sse 0 C to 70 C 95 96 Altitude Opertalilig iioii edicere iari 2000 meters Storage lt 12000 meters Vibration and Shock Complies with MIL PRF 28800F Class 3 Safety einen 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 Il Equipment Class 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 l j nme ae EN50081 1 Class B EN5501 1 22 EN61326 1 1998 EN50082 1 EN55011 1991 Class B EN61000 6 1 2001 FCC Rules part 15 sub part J class B CETL and CE marked Measurement Isolation Guard to Safety Ground n 3300 pF gt 10 GO Lo to Guard In Remote Guard eee lt 2800 pF gt 10 GQ Not in Resistance function In Local Guard sese Lo and Guard terminals are internally shorted in Resistance 2800 pF gt 10 GQ Autorange Range UP m M M 100 of range Range D
10. 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 Remove the bottom shield 5 a Remove the six philips screws from the shield b Slide the shield toward front of unit and lift it out Locate and remove the screw holding the input sense connector group to the chassis 6 Cut the tie holding the input sense connector cable to the chassis Using a pair of long nose pliers release depress the latch on each of the three standoff clips holding the A6A1 Rear Input PCA to the Al DC PCA With all three latches released on the standoffs gently unplug the A6A1 Rear Input PCA from the Al DC PCA by lifting it straight up and away from its connectors on the Al DC PCA 7 avw016f eps Figure 4 8 Removing the A6 Rear Input Assembly 8508A Service Manual Fuse Replacement and Line Voltage Selection A Caution To avoid fire hazard use only the fuse arrangements that appear in the fuse specification Tables 4 1 and 4 2 below Additionally the supply network must be fused at a maximum of 16 A and if the power cable plug is internally fused a 5 A fuse must be fitted in the power cable plug To avoid shock hazards disconnect all line power and input terminal connections before attempting to access the fuse s Line Power Fuse F1 and Voltage Selection The power input and voltage selection module on the rear of th
11. b Slide the cover toward the back of the unit and lift it off Remove the bottom shield 3 a Remove the six philips screws from the shield b Slide the shield toward front of unit and lift it out Remove the Al DC PCA 4 Disconnect the Rear Input PCA from the A1 DC PCA Disconnect the five connectors from the rear edge of the A1 DC PCA Disconnect the 10 connectors from the front edge of the A1 DC PCA Disconnect the red and black wires from the screw termininals on the PCA Remove the two philips screws from the Al DC PCA Slide the A1 DC PCA to the side and lift it from the chassis mogocsg avw010f eps Figure 4 2 Removing the A1 DC PCA 4 5 8508A Service Manual Removing the A2 AC PCA Use the following procedure to remove the A2 AC PCA See Figure 4 3 l 2 Position the unit on the work surface so it is top side up Remove both rear feet 1 a Remove the three hex screws from each foot b Ifthe feet are still in place pull them from the unit Remove the top cover 2 a Remove the one philips screw at rear of the top cover b Slide the cover toward the back of the unit and lift it off Remove the top shield 3 a Remove the four philips screws from the shield 4 b Slide the shield toward front of unit and lift it out Remove the A2 AC PCA 5 Remove the eight philips screws holding the shield to the A2 AC PCA Lift the shield from the
12. calibration state To avoid accidental mis calibration do not attempt to operate the Multimeter in External Trigger mode from the front panel when in Cal and only press the SAMPLE key when a calibration operation is intended to be performed Calibration Menu 8 4 This menu allows calibration operations at the calibration point nominal values via Auto or selection of calibration operations at non nominal values via Set It also offers access to the special calibration menu The CAL legend appears in the left hand display when in CAL mode adj134f eps CALIBRATION Menu Calibration and Verification 3 Calibration Menus This menu defines four menu keys Ruta Indicates to the user that the calibration point is automatically set according to the amplitude and frequency in ACV of the signal detected Auto is the default selection on entry to the CALIBRATION menu Refer to the tables appearing later in this chapter for the calibration points for the selected range An indication of the use of the SAMPLE key is also displayed The Set feature is available in all functions allowing the user to enter the true value of the calibration standard where it differs from nominal calibration point value Pressing Set displays the SET VALUE menu except in ACV Spot Frequency mode when the SPOT CAL menu is displayed Spot Frequency calibration reduces flatness errors within 10 of the spot frequency Set is not available for DCV DCI and Resist
13. 10k 700 120 800 120 800 120 815 120 860 120 10k 30k 0 25 120 0 3 120 0 3 120 0 3 120 0 3 120 20A 19 999 00 10 2k 800 120 900 120 900 120 900 120 920 120 2k 10k 0 2 120 0 25 120 0 25 120 0 25 120 0 25 120 1 8508A Service Manual AC Current Secondary Specifications 99 Temperature Coefficient 5 C 15 C Input Impedance Q Range Frequency Hz 15 C 30 C 30 C 40 C ppm Reading C Range Front Rear 200 uA 2 mA amp 1 10 10 15 200 uA 150 150 20 mA 10 10k 10 15 2mA 15 2 15 2 10k 30k 12 20 20 mA 1 8 1 9 30 k 100 k 40 60 200 mA 1 10 10 15 1 2 1 3 10 10k 15 20 10k 30k 15 20 2A 10 2k 10 15 0 3 0 4 2k 10k 15 20 10k 30k 20 30 20A 10 2k 20 25 0 04 2k 10k 25 30 Typen este ete cee ks True rms AC coupled DC coupled gives JJ ac dc Crest Factor 3 1 at 50 range 1 5 1 at full range Protection FRONGIN PUL occi ce ame ee Sic tt Ea 20 A rms Rear Input ionic een 2 A rms Rear Panel Fuse Settling Time 200 uA to 200 mA Ranges 2 A Range 20 A Range at 10 A to 100 ppm of step to 100 ppm of step to 300 ppm of step 100 Hz filter et n entes 0 5s 1s 1s 40 Hz filter 125s 2s 2s 10 Hz filter lt 5s lt 10s lt 10s TAZ filte iuc oie rette a treten oes 50s 50s 50s Introduction and Specifications Specifications Resistance Resistanc
14. 180 80 190 80 10 40 80 25 115 25 115 25 135 25 145 25 40 10k 60 25 90 25 90 25 110 25 140 25 10k 30k 115 50 240 50 240 50 250 50 265 50 30 k 100 k 270 250 600 250 600 250 615 250 700 250 8508A Service Manual AC Voltage Secondary Specifications Temperature Coefficient A m 5 C 15 C Range Frequency Hz 15 C 30 C 30 C 40 C ppm Reading C 200 mV 1 10 5 10 10 40 5 10 40 100 5 10 100 2k 5 10 2k 10k 12 20 10k 30k 15 20 30 k 100 k 40 60 2V 1 10 5 10 20V 10 40 5 10 200 V 40 100 5 10 100 2k 5 10 2k 10k 10 15 10k 30k 12 20 30 k 100 k 40 60 100 k 300 k 60 90 300 k 1M 80 120 1000 V 1 10 5 10 10 40 5 10 40 10k 10 15 10k 30k 12 20 30k 100k 40 60 CMRR 1 KQ unbalance Crest Factor 200 mV to 200 V ranges 1000 V range ssesessses Protection All ranges Input Impedance DC Accuracy DC Coupled Ratio Accuracy Range to Range en Within Range Settling Time to 100 ppm step size 100 Hz filter 40 Hz filler ae en 10 Hz filter TAZ AION ret ete eren Frequency Measurement Signal Amplitude Range Gate Mode Resolution Frequency Range Accuracy 1 year 13 C 33 C Sample Interval BEER EEE True rms AC coupled measures AC c
15. 4 0 9 11 5 0 9 12 0 0 9 200 Q 199 990 000 Lo Current 3 0 0 9 6 5 0 9 8 5 0 9 9 5 0 9 10 0 0 9 2 KQ 1 999 900 00 Lo Current 3 0 0 9 6 5 0 9 8 5 0 9 9 5 0 9 10 0 0 9 20 KQ 19 999 000 0 Lo Current 3 0 0 9 6 5 0 9 8 5 4 0 9 9 5 0 9 10 0 0 9 200 kQ 199 990 000 Lo Current 6 0 0 6 8 0 0 6 9 0 0 6 9 5 0 6 10 0 0 6 2MQ 1 999 900 00 Lo Current 8 0 0 6 10 0 0 6 12 0 0 6 13 0 0 6 17 0 0 6 20 MQ 19 999 000 0 Lo Current 25 6 0 25 6 0 30 6 0 45 6 0 110 6 0 200 MQ 199 990 000 Lo Current 325 600 450 600 650 600 670 600 1810 600 2 GQ 1 999 900 00 Lo Current 325 600 450 600 650 600 675 600 1810 600 20 MQ 19 999 000 0 High Voltage 2 5 0 6 5 0 0 6 8 5 4 0 6 19 0 6 20 0 6 200 MQ 199 990 000 High Voltage 4 5 6 0 7 5 4 6 0 12 6 0 75 6 0 80 4 6 0 2 GQ 1 999 900 00 High Voltage 25 60 30 60 35 60 195 60 230 60 20 GQ 19 999 000 0 High Voltage 325 600 450 600 650 600 675 600 1810 600 1 8508A Service Manual Resistance Normal Mode Secondary Specifications 9 Transfer Uncertainty Temperature Coefficient Range Measurement Current ne din 15 C 30 C AA ppm Range ppm Reading C 20 100 mA 2 0 2 0 1 5 2 5 20 Q 10 mA 0 8 0 7 0 6 1 0 200 Q 10 mA 0 2 0 15 0 5 0 8 2 kQ 1mA 0 2 4 0 15 0 5 0 8 20 kQ 100 uA 0 2 0 15 0 5 0 8 200 kQ 100 uA 0 2 4 0 15 0 5 0 8 2 MQ 1
16. Gain calibration or for AC ranges whether it is to be a Zero LF Gain or HF Gain calibration As part of the calibration procedure a non volatile input offset compensation is adjusted independently for the front and rear inputs The autocal process can operate only when the rear panel Calibration switch is in the Enable position Applying an integrity seal or calibration sticker to prevent access to the rear panel Calibration switch is a convenient way to ensure the security of calibration When a calibration operation is performed the Multimeter s internal calibration memory is immediately updated It is possible to calibrate 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 specifications required The performance of the Multimeter is specified for periods of 365 days and 90 days if recalibration takes place on a 90 day cycle use the 90 day specifications for improved performance During manufacture the Multimeter is calibrated with low uncertainties reflected in the Absolute Specifications listed in Chapter 1 Introduction and Specifications After recalibration the user should apply the ca
17. Multimeter press CAL to enter the CALIBRATION menu 4 Press SAMPLE to initiate the calibration operation Calibration is complete when the Busy legend goes out and the calibrated measurement is displayed Range Gain Point 3 24 1 On the Calibrator select Range Gain point Output value Alternatively if using a standard resistor re connect the standard resistor to measure its resistance For the 2 GQ range the 8508 7000K 1 GQ standard resistor is used in place of the calibrator For the 200 MQ range and above de select Ex SNS on the calibrator and de select 4WQ on the Multimeter Calibration of the 20 GQ range gain point takes place automatically when calibrating 2 GQ range and calibration against an external standard is optional if a suitable standard is available 2 Onthe Multimeter Press CAL to revert to CALIBRATION menu Select Set on the CALIBRATION menu 4 Use the numeric keys with the SET VALUE menu to key in the true output value of the calibrator or the value of the resistance standard at the range gain value then press Enter Routine Calibration Calibration and Verification 3 Press SAMPLE to initiate the calibration operation Calibration is complete when the Busy legend goes out and the calibrated measurement is displayed On the Calibrator set STANDBY Press the Q key to revert to the ranges menu DC Current Calibration AA Warning The Calibrator can deliver a lethal electric shock To avoid ele
18. PCA Disconnect the one connectors from the rear edge of the A2 AC PCA Disconnect the three connectors from the front edge of the A2 AC PCA Remove the four philips screws from the PCA Using a flat blade screwdriver remove the four plastic standoffs from the PCA Lift the A2 AC PCA from the chassis wmernecp 4 6 avw011f eps Figure 4 3 Removing the A2 AC PCA Maintenance 4 Access Procedures Removing the A3 Ohms PCA Use the following procedure to remove the A3 Ohms PCA See Figure 4 4 1 2 Position the unit on the work surface so it is bottom side up Remove both rear feet 1 a Remove the three hex screws from each foot b Ifthe feet are still in place pull them from the unit Remove the bottom cover 2 a Remove the one philips screw at rear of the bottom cover b Slide the cover toward the back of the unit and lift it off Locate the two connectors on the A1 DC PCA with the green red orange yellow and the black brown wires 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 Position the unit on the work surface so it is top side up Remove the top shield 3 a Remove the four philips screws from the shield b Slide the shield toward front of unit and lift it out Remove the A3 Ohms PCA 4 a Disconnect the two
19. Range Voltage Frequency 8508A Filter Tolerance 200V 100V 20 Hz 10Hz 0 0144 V 100 V 55 Hz 40 Hz 0 0119 V 100 V 1 kHz 100 Hz 0 0099 V 100 V 3 kHz 100 Hz 0 0119 V 100 V 10 kHz 100 Hz 0 0119 V 100 V 30 kHz 100 Hz 0 0295 V 100 V 60 kHz 100 Hz 0 0795 V 100 V 100 kHz 100 Hz 0 0795 V 1000 V 500 V 55 Hz 40 Hz 0 088 V 500 V 1 kHz 100 Hz 0 088 V 500 V 3 kHz 100 Hz 0 088 V 500 V 10 kHz 100 Hz 0 088 V 500 V 30 kHz 100 Hz 0 223 V 1000 V 1 kHz 100 Hz t 0 331 V 1000 V 30 kHz 100 Hz t1 476V 1 Based on 365 day Tcal 1 C 99 CL Absolute specifications See comments in Applicable Verification Tolerance section above regarding the impact of calibration uncertainties and use of other specifications Resistance Checks When verifying the resistance function each of the resistance modes NormalQ TruQ LoIQ and HiVQ 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 same resistance standard several times during the calibration sequence A 1 GQ standard resistor is used for ranges above 200 MQ as the highest resistance available from the 5720A calibrator is 100 MQ Equipment Configuration l SE e A PS Ensure that the calibrator output is set to STANDBY and configured for In
20. Table 4 5 for descriptions of unexpected exception errors Table 4 5 Unexpected Exception Errors id Exception oe bus error usually due to addressing non existant memory or IO Ux address error due to attempting a word access to an odd address Di illegal instruction us zero divide na privilege violation 0a trace trace facility is not used i unimplemented instructions ii unimplemented instructions z4 spurious interrupt most likely cause is noise a003 FROM Sumcheck Failure S004 FAM Check Failure Maintenance Self Test a003 Serial Interface Fault Adde id When this fatal error occurs the system will continuously try to repeat whatever it was doing the user interface will be inoperative See Tabe 4 6 for descriptions of the serial interface errors Table 4 6 Serial Interface Errors id Fault i Phase Error The phase counter is either out of range for the current sequence or an interrupt from the serial interface or delay timer occurred the other was expected Probably due to corruption of the phase counter This could be either a software or a hardware fault DIE NOT Transfer Complete a Tx_complete status was false when interrupt on Tx complete received b Tx_complete did not become true within timeout period when on RTx received Both caused by fault in interface hardware probably digital ULA fault True Complement Error True compl err
21. appropriate operating temperature range will be adequate However performance at other temperatures may be determined by including an allowance for temperature coefficient over the additional temperature range Care should be taken when making this calculation as an amount of temperature coefficient is already included in the 8508A specifications and those specifications are themselves based on combining contributions using techniques similar to those employed in uncertainty analysis For example consider operating at 33 C 10 C from the 23 C calibration temperature The 5 C specifications already include a contribution for 5 C of temperature difference so this amount of temperature effect must be removed before the effect of the 10 C difference is added Consider 10 V on the 20 VDC range 365 day absolute specification 95 96 at 33 C expressed in parts per million of 10 V is 2 x 85 02x2 5 x 0 3 10 x 0 5 6 16 ppm of 10 V 1 20 Introduction and Specifications 1 Applying the Specifications Ratio Measurements The 8508A Ratio mode will automatically take measurements of inputs applied to the front and rear terminals and display the result as a ratio in the voltage and resistance functions The measurements can be made on the same range or different ranges When making measurements on different ranges the error in each measurement is evaluated by applying the relevant specification for each range and combining the
22. n a n a Rear input n a 2A 2A n a n a n a Notes Resistance and Temperature Ground Note 1 8 The Sense Lo Sense Hi and Hi Terminals are open circuit in these functions The front input A terminal protection is automatic and self resetting and does not interrupt current flow Damage is likely to occur if more than 20 A is applied The rear input A terminal is protected by a fuse mounted on the rear panel Maximum rms terminal voltages Sense Hi Hi 250V Sense Lo 250V 250V Lo 250 V 250 V 250V A 250V 250V 250 V 250V Guard 250V 250V 250 V 250 V 250V DigGnd 650 V 650 V 650 V 650 V 1000 V 1000 V OV 650 V 650 V 650 V 650 V 1000 V 1000 V The A terminal is open circuit in these functions Introduction and Specifications Specifications DC Voltage DC Voltage Uncertainty Relative to Cal Stds Absolute Uncertainties Range Full Scale ppm Reading ppm Range 24 hour 90 day 365 day 365 day 365 day TCal TCal 1 C TCal 1 C TCal 1 C TCal 1 C 5 C 95 Confidence Level 200 mV 199 990 000 0 7 0 5 1 4 4 0 5 2 7 0 5 4 5 4 0 5 5 0 4 0 5 2V 1 999 900 00 0 5 0 2 1 4 0 2 2 7 0 2 3 0 0 2 3 5 0 2 20 V 19 999 000 0 0 5 0 2 1 4 0 2 2 7 0 2 3 0 0 2 3 5 0 2 200 V 199 990 000 1 0 0 2 2 6 0 2 4 0 0 2 4 5 0 2 5 5 0 2 1000 V 1050 000 00 1 0 0 5 2 6 0 5 4 0 0 5 4 5 4 0 5 5 5
23. necessary to maintain the Multimeter at a module or board level A brief description of the information contained in the various chapters follows Chapter 1 ntroduction and Specification provides a brief description of the product safety information regarding the product and its use and a complete set of detailed specifications Chapter 2 Theory of Operation provides an overall functional description of the internal workings of the Multimeter The intent of the theory is to aid in locating and isolating a faulty PCA Chapter 3 Calibration and Verification provides a thorough and complete description of both the Verification and the Calibration procedures for the Multimeter Chapter 4 Maintenance provides detailed descriptions of how to disassemble the Multimeter to the PCA level The purpose 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 AA Warning To avoid electric shock personal injury or death carefully read the information under Safety Considerations before attempting to install use or service the Multimeter Safety Considerations This instrument has been designed and tested in accordance with the European standard publication EN61010 1 2001 and U S Canadian standard publications UL 61010 1A1 and CAN CSA C22 2 No 61010 1 The in
24. 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 Onthe Multimeter select the required range 2 Onthe Calibrator select zero and Operate Alternatively if using a standard resistor connect the standard resistor for a 4 wire resistance zero For the 200 MQ and 2 GQ ranges de select EX SNS on the calibrator and de select 4WQ on the Multimeter On the Multimeter press CAL to enter the CALIBRATION menu 4 Press SAMPLE to initiate the calibration operation 3 19 8508A Service Manual Calibration is complete when the Busy legend goes out and the calibrated measurement is displayed Range Gain Point 1 On the Calibrator select the Range Gain point resistance value Alternatively if using a standard resistor re connect the standard resistor to measure its resistance For the 2 GQ range the 8508 7000K 1 GQ standard resistor is used in place of the calibrator For the 200 MQ and 2 GQ ranges de select EX SNS on the calibrator and de select 4WQ on the Multimeter 2 On the Multimeter Press CAL to revert to CALIBRATION menu Select Set on the CALIBRATION menu 4 Use the numeric keys with the SET VALUE menu to key 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 to initiate the calibration operation Calibration is complete when the Busy leg
25. performing the following calibration procedures e Never touch any lead or terminal unless you are absolutely certain that no dangerous voltage is present e Make sure that signal leads are in a safe condition before you handle them in any way Equipment Configuration l 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 ACV key 4 Press the CONFIG key Select Tfer On and RESL6 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 200mV range and working up to the 1kV range as listed in Table 3 9 l 2 Select the required range on the multimeter On the Multimeter press CONFIG and select the appropriate filter for the point being verified as listed in Table 3 9 On the calibrator set the output to the voltage and frequency for the point being verified as listed in Table 3 9 Set the output to OPERATE Note the Multimeter s reading Compare the result with the allowable tolerance taking into account any known error from nominal of the calibrator for this output Repeat steps 2 4 for each point to be verified on the Multimeter s range to be verified Repeat steps 1 5 for each Multi
26. sse 13 34 3 9 AC Voltage Verification Points and Sequence ssssssssseene 3 36 3 10 Resistance Verification Points and Sequence cnnensesneesneesnensnnnsnnennenn nenne 13 39 3 11 DC Current Verification Points and Sequence sse 3 41 3 12 AC Current Verification Points and Sequence sse 3 42 4 1 Power Input Fuse 1 ener ennt enne inr rennen nnns 14 12 4 2 Current Function Rear Input Fuse 2 nennen nennen 14 13 43 Se Test Errors eene tenete danses aieiai oaeaeei 14 13 4 4 9000 System Kernel Fault Errors sess enne 4 16 4 5 Unexpected Exception Errors enne nnne tese nee 4 16 4 6 Serial Interface ErfOrs euasit ied co ER SR co ede CERE HES EUER UE de AAEE a a UY none 14 17 4 7 Serial Loop Mismatch Errors sess nenne 14 18 4 8 Execution EHOIES2 cie nte shake deua RE XE RAE Ce NEA 14 19 4 9 Device Dependent Errors ueeeessessseessennsennnennnennneennennnennnennnnnnnnsnnnnennnnense nenne 4 20 5 1 8508A Final Assembly nrnna nainn N enne nennen nnns 5 4 5 2 8508A Chassis Assembly scissa iaa asai 5 6 5 2 Bezel front panel Assembly essere ener 5 7 5 4 A6Rear Input Assembly optional sss rennen 8508A Service Manual vi List of Figures Figure Title Page 1 1 8508A Dimentional Outline Drawing essent 1 6 2 1 8508A Functional Block Dia
27. the Busy legend goes out and the calibrated measurement is displayed Range Gain Point 1 On the Calibrator select Range Gain point Output value Alternatively if using a standard resistor re connect the standard resistor to measure its resistance On the Multimeter Press CAL to revert to CALIBRATION menu Select Set on the CALIBRATION menu Use the numeric keys with the SET VALUE menu to key in the true output value of the calibrator or the value of the resistance standard at the range gain value then press Enter Press SAMPLE to initiate the calibration operation Calibration is complete when the Busy legend goes out and the calibrated measurement is displayed On the Calibrator set STANDBY Press the Q key to revert to the ranges menu Tru Lol Mode Calibration l 2 Press the Q Plus key and select TruQ From the Tru menu select the 2 range Press the CONFIG key and select Filt Lol and 4wQ 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 Tru Lol mode Just one range can be calibrated if required but for a full calibration start with the 2 Q range and work up to the 20 kQ range On each range the Multimeter automatically recognizes the appropriate value as range Zero or range gain from the applied resistance value Note It is unlikely that the re
28. ve 100 uA Range Gain ve 100 uA 2 mA Zero 0 mA Range Gain ve 1 mA Range Gain ve 1 mA 20 mA Zero 0 mA Range Gain ve 10 mA Range Gain ve 10 mA 200 mA Zero 0 mA Range Gain ve 100 mA Range Gain ve 100 mA 2A Zero 0A Range Gain ve 1A Range Gain ve 1A 20A Zero OA Range Gain ve 10A Range Gain ve 10A 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 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 or range gain from the applied signal amplitude and polarity 2 3 4 On the Multimeter select the required range On the Calibrator set to zero output and Operate On the Multimeter press CAL to enter the CALIBRATION menu Press SAMPLE to initiate the calibration operation Calibration is complete when the Busy legend goes out and the calibrated measurement is displayed Calibration and Verification 3 Routine Calibration Range Gain Points 1 2 3 4 en 7 8 9 On the Calibrator select the positive Range Gain point Output val
29. 0 uA 0 5 0 5 0 6 1 0 20 MQ 1 uA 2545 2 3 200 MQ 100 nA 15 50 20 30 2GQ 10 nA 200 4 500 200 300 Resistance Lo Current Mode Secondary Specifications 9 Transfer Uncertainty Temperature Coefficient Range Measurement Current Apis pon iind 15 C 30 C ne ppm Range ppm Reading C 20 100 mA 2 0 2 0 1 5 2 5 20 Q 10 mA 0 8 0 7 0 6 1 0 200 Q 1mA 0 8 0 7 0 6 1 0 2 kQ 100 uA 0 8 0 7 0 6 1 0 20 kQ 10 uA 0 8 0 7 0 6 1 0 200 kQ 10 pA 0 5 0 5 0 6 1 0 2 MQ 1 pA 2 0 0 5 2 3 20 MQ 100 nA 15 5 20 30 200 MQ 10 nA 200 500 200 300 2 GQ 10 nA 200 500 200 300 Resistance High Voltage Mode Secondary Specifications Transfer Uncertainty Temperature Coefficient Range Measurement Current on needing 15 C 30 C ne ppm Range ppm Reading C 20 MQ 10 uA 0 5 0 5 0 6 1 0 200 MQ 1uA 2 0 0 5 2 0 3 2 GQ 100 nA 15 50 20 30 20 GQ 10 nA 200 4 500 200 300 Full Scale Measurement Voltage Normal Mode Lo Current Mode High Voltage Mode Protection All ranges Ratio Accuracy Range to Range sssssssseseeeenene Within Range Settling Time ee csl E tis Mun 200 mV 2 V 20 V 200 mV 2 V 200 V 250 V rms 360 V pk 10 Q in any or all leads 1 Q on 2 Q range depends on external connections True 4 wire with Ohms guard 2 wire selectable Net Front Input Accuracy Net Rear Input Accuracy Apply 24 hour or 20 minute Transfer Uncertainty specifications Up to 200 kO range generally the sam
30. 00 00 Lo Current 7 0 0 5 8 0 0 5 9 0 0 5 104 0 5 1540 5 20 MQ 19 999 000 0 Lo Current 20 5 0 20 5 0 25 5 0 35 5 0 90 5 0 200 MQ 199 990 000 Lo Current 250 4 500 350 500 500 500 515 500 1505 500 2 GQ 1 999 900 00 Lo Current 250 500 350 500 500 500 525 500 1510 500 20 MQ 19 999 000 0 High Voltage 2 0 0 5 4 0 0 5 7 0 4 0 5 1540 5 17 0 5 200 MQ 199 990 000 High Voltage 3 5 5 0 6 0 4 5 0 9 0 5 0 60 5 0 65 5 0 2 GQ 1 999 900 00 High Voltage 20 50 25 50 30 50 150 50 180 50 20 GQ 19 999 000 0 High Voltage 250 500 350 500 500 500 525 500 1510 500 99 Confidence Level 20 1 999 900 00 Normal 6 04 2 5 1042 5 1242 5 1942 5 2242 5 200 19 999 000 0 Normal 3 0 0 9 5 5 4 0 9 8 5 0 9 11 5 0 9 12 0 0 9 200 Q 199 990 000 Normal 1 8 0 3 5 0 4 0 3 8 5 0 3 9 5 0 8 10 0 3 2 kQ 1 999 900 00 Normal 1 2 0 3 4 5 4 0 83 8 5 0 8 9 5 0 3 10 0 3 20 KQ 19 999 000 0 Normal 1 2 4 0 3 4 5 0 8 8 5 0 3 9 5 0 8 10 0 3 200 kQ 199 990 000 Normal 1 2 4 0 3 4 5 0 8 8 5 0 3 9 5 0 8 10 0 3 2 MQ 1 999 900 00 Normal 2 5 0 6 5 0 0 6 8 5 0 6 10 5 0 6 12 0 6 20 MO 19 999 000 0 Normal 4 5 6 0 7 5 4 6 0 12 6 0 20 6 0 25 6 0 200 MQ 199 990 000 Normal 25 60 30 60 35 60 75 60 150 60 2 GQ 1 999 900 00 Normal 325 600 450 600 650 600 675 600 1810 600 20 1 999 900 00 Lo Current 6 04 2 5 1042 5 1242 5 1942 5 2242 5 200 19 999 000 0 Lo Current 3 0 0 9 5 5 4 0 9 8 5
31. 00 Hz 0 0830 uA 100 uA 1 kHz 0 0830 uA 100 uA 3 kHz 0 0830 LA 100 uA 5 kHz 0 0830 LA 100 uA 10 kHz 0 0830 LA 2mA 1mA 300 Hz 0 000580 mA 1mA 1 kHz 0 000580 mA 1mA 3 kHz 0 000580 mA 1mA 5 kHz 0 000580 mA 1mA 10 kHz 0 000580 mA 20 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 10 mA 10 kHz 0 00580 mA 200 mA 100 mA 300 Hz 0 0545 mA 100 mA 1 kHz 0 0545 mA 100 mA 3 kHz 0 0545 mA 100 mA 5 kHz 0 0545 mA 100 mA 10 kHz 0 0545 mA 2A 1A 300 Hz 0 000945 A 1A 1 kHz 0 000945 A 1A 3 kHz 0 001055 A 1A 5 kHz 0 001055 A 1A 10 kHz 0 001055 A 20A 10A 300 Hz 0 01140A 10A 1 kHz 0 01140A 10A 3 kHz 0 02740 A 10A 5 kHz 0 02740 A 10A 10 kHz 0 02740 A 1 Based on 365 day Tcal 1 C 99 CL Absolute specifications See comments in Applicable Verification Tolerance section above regarding the impact of calibration uncertainties and use of other specifications 3 42 Calibration and Verification 3 Performance Verification Frequency Checks Equipment Configuration 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 ACV key select the 2V range 4 Press the CONFIG key Select Tfer On Filt 40Hz 5 Confirm that the 8508A is configured for internal guard External Guard is deselected by checking that the Ex
32. 08 7000K 1 GQ standard resistor is used in place of the calibrator For the 200 MQ range and above de select Ex SNS on the calibrator and de select AWO on the Multimeter 9 Set the calibrator output to STANDBY 3 38 10 Press the Q key 11 Press the CONFIG key and select Filt RESL7 4w and Lol 12 Repeat steps 3 9 for the NormalQ Lol ranges 13 Press the Q Plus key and select TruQ 14 Press the CONFIG key and select Filt RESL7 and 4wQ Ensure Lol is deselected 15 Repeat steps 3 9 for the TruQ ranges 16 Press the Q Plus key and select TruQ 17 Press the CONFIG key and select Filt RESL7 4w and Lol 18 Repeat steps 3 9 for the TruQ Lol ranges 19 Press the O Plus key and select HiVQ 20 Press the CONFIG key and select Filt RESL7 and 4wQ 21 Repeat steps 3 9 for the HiVO ranges Calibration and Verification Performance Verification Table 3 10 Resistance Verification Points and Sequence 8508A Range Resistance Tolerance Normal Q and Trun Normal Q Lol and TruQ Lol 20 00 Perform input zero operation to calibrator range locked zero output 190 0 0000240 Q 0 0000240 Q 20 Q 0Q Perform input zero operation to calibrator range locked zero output 100 0 000133 Q 0 000133 Q 200 Q 00 Perform input zero operation to calibrator range locked zero output 100 Q 0 00101 Q 0 00113 Q 2 kQ 0 kQ Perform input zero operation to calibra
33. 0k 30k 500 100 600 100 600 100 650 100 710 100 30k 100k 0 35 100 0 4 100 0 4 100 0 4 100 0 4 100 200 mA 199 990 0 1 10 200 100 250 100 250 100 290 100 310 100 10 10k 200 100 250 100 250 100 250 100 290 100 10k 30k 500 100 600 100 600 100 600 100 625 100 2A 1 999 900 10 2k 500 100 600 100 600 100 600 100 620 100 2k 10k 600 100 700 100 700 100 710 100 735 100 10k 30k 0 25 100 0 3 100 0 3 100 0 3 96 100 0 3 100 20A 19 999 00 10 2k 700 100 800 100 800 100 800 100 820 100 2k 10k 0 2 100 0 25 100 0 25 100 0 25 100 0 25 100 99 Confidence Level 200 uA 199 990 0 1 10 250 120 300 120 300 120 590 120 620 120 10 10k 250 120 300 120 300 120 590 120 620 120 10k 30k 600 120 700 120 700 120 775 120 800 120 30 k 100 k 0 35 120 0 4 120 0 4 96 120 0 4 96 120 0 4 96 120 2mA amp 1 999 900 1 10 250 120 300 120 300 120 380 120 400 120 20 mA 19 999 00 10 10k 250 120 300 120 300 120 340 120 370 120 10k 30k 600 120 700 120 700 120 775 120 800 120 30 k 100 k 0 35 120 0 4 120 0 4 120 0 4 96 120 0 4 96 120 200 mA 199 990 0 1 10 250 120 300 120 300 120 380 120 400 120 10 10k 250 120 300 120 300 120 305 120 360 120 10k 30k 600 120 700 120 700 120 700 120 740 120 2A 1 999 900 10 2k 600 120 700 120 700 120 705 120 725 120 2k
34. 4 0 5 99 Confidence Level 200 mV 199 990 000 0 8 0 6 2 0 0 6 3 5 0 6 6 0 0 6 6 5 0 6 2V 1 999 900 00 0 6 0 25 1 8 0 25 3 5 0 25 4 0 0 25 4 5 0 25 20 V 19 999 000 0 0 6 0 25 1 8 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 4 0 6 3 5 0 6 5 2 0 6 6 0 0 6 7 0 0 6 DC Voltage Secondary Specifications 71 Temperature Coefficient Transfer Uncertainty 5 C 15 C Range 20 mins 1 C ppm 15 C 30 C 30 C 40 C Reading ppm Range ppm Reading C 200 mV 0 4 4 0 3 0 4 0 6 2V 0 12 0 1 0 3 0 5 20 V 0 12 0 1 0 3 0 5 200 V 0 4 0 1 0 7 1 0 1000 V 0 4 0 3 0 7 1 0 D m Multi slope multi cycle A D Converter CMRR 1 KQ unbalance P 140 dB at DC and 1 60 Hz NMRR P Filler OUt accom aan 60 dB at 50 60 Hz 0 09 96 lige ae 110 dB at 50 60 Hz 0 09 96 Protection All ranges Input Impedance 200 mV to 20 V Ranges 200 V amp 1000 V Ranges Max Input Current Ratio Accuracy Range to Range sessssssseseeeeeenetne NER erae et edu 1 kV rms ite ee gt 10GQ P 10 1 MO amp 1 96 O 50 pA Within Range cerei ee Settling Time to 10 ppm step size gs Pm lt 50 ms Filter In ertet as 1s Net Front Input Accuracy Net Rear Input Accuracy Apply 24 hour or 20 minute Transfer Uncertainty specifications 1 1 9 8508A Service Manual
35. 50 100 500 100 500 100 505 100 570 100 100 k 300k 0 15 0 1 6 0 3 96 0 1 96 0 3 96 0 1 96 0 3 26 0 1 96 0 3 0 1 300k 1M 1 96 4 0 5 96 196 196 1 1 1 1 1 1 1000 V 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 10k 50 20 80 20 80 20 95 20 115 20 10k 30k 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 115425 115 25 125 25 135 25 100 2k 45 12 115 12 115 12 125 12 135 12 2k 10k 70425 115 25 115 25 125 25 165 25 10k 30k 270 35 340 50 340 50 345 50 395 50 30 k 100 k 450 120 750 120 750 120 755 120 855 120 2V 20V amp 1 999 900 1 10 80 70 115 70 115 70 180 70 190 70 200 V 19 999 00 10 40 80 12 115 12 115 12 120 12 135 12 199 990 0 40 100 60 12 90 12 90 12 95 12 110 12 100 2k 35 4 12 70 12 70 4 12 75 4 12 90 12 2k 10k 60 12 90 12 90 12 95 12 135 12 10k 30k 115 25 240 25 240 25 245 25 260 25 30 k 100 k 270 120 550 120 550 120 555 120 650 120 100 k 300k 0 15 0 12 0 3 0 12 0 3 0 12 0 3 0 12 0 3 0 12 300k 1M 1 96 4 0 6 96 1 96 4 1 2 96 1 96 4 1 2 96 1 4 1 2 6 1 96 4 1 2 1000 V 1050 000 1 10 80 80 115 80 115 80
36. 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 ay Note This instrument may contain a Nickel Cadmium battery Do not mix with the solid waste stream Spent batteries should be disposed of by a qualified recycler or hazardous materials handler Contact your authorized Fluke service center for recycling information 5 3 8508A Service Manual Parts Lists The following tables list the replaceable parts for the 8508A Reference Multimeter Parts are listed by assembly alphabetized by reference designator Each assembly is accompanied by an illustration showing the location of each part and its reference designator The parts lists give the following information e Reference designator e An indication if the part is subject to damage by static discharge e Description e Fluke stock number e Total quantity e Any special notes i e factory selected part A Caution A symbol indicates a device that may be damaged by static discharge Table 5 1 8508A Final Assembly Reference Description Fluke Tot Notes Designator Part No Qty MP1 Top Cover 1988598 1 MP2 Bottom Cover 1988604 1 MP3 Cover Stripe Side 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 Sti
37. After the initial setup and connecting up use the following procedure to calibrate range Zero then positive and negative range gains on all DCV ranges Just one range can be calibrated if required but for a full calibration start with the 200 mV range and work up to the IkV range as shown in Table 3 3 Table 3 3 DC Voltage Calibration Points and Sequence 8508A Range Point Voltage 200 mV Zero 0 mV Range Gain ve 100 mV Range Gain ve 100 mV 2V Zero OV Range Gain ve 1 V Range Gain ve 1 V 20 V Zero OV Range Gain ve 10 V Range Gain ve 10V 200 V Zero OV Range Gain ve 100 V Range Gain ve 100 V 1000 V Zero OV Range Gain ve 1000 V Range 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 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 or range gain from the applied signal amplitude and polarity Zero Point 1 2 3 4 On the Multimeter select the required range On the Calibrator set z
38. BY 7 Press the Q key to revert to the ranges menu Tru2 Mode Calibration 1 Press the Q Plus key and select TruQ From the TruQ menu select the 2 Q range 2 Press the CONFIG key and select Filt and 4wQ Ensure Lol is deselected 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 TruQ mode Just one range can be calibrated if required but for a full calibration start with the 2 Q range and work up to the 20 kQ range On each range the Multimeter automatically recognizes the appropriate value as range zero or range gain from the applied resistance value Note It is unlikely that the resistance standard will be at exactly the nominal value required The Set feature allows 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 3 21 8508A Service Manual 3 22 Zero Point 1 Onthe Multimeter select the required range 2 On the Calibrator select zero Q and Operate Alternatively if using a standard resistor connect the standard resistor for a 4 wire resistance zero On the Multimeter press CAL to enter the CALIBRATION menu 4 Press SAMPLE to initiate the calibration operation Calibration is complete when
39. E ALL WIRES EXCEPT GREEN NOTE POSITION CAPACITOR AWAY FROM OTHER TERMINALS avw029f eps Figure 5 3 A5 Bezel front panel Assembly 5 11 8508A Service Manual 5 12 Table 5 4 A6 Rear Input Assembly optional Reference Designator At C1 C2 Art FH H1 H2 H3 H4 H5 H6 H7 H8 H9 H10 H11 H12 H13 H14 J2 J4 J1 J3 J5 J6 L1 wi Description Rear Input PCA Capicator CD 470 pF 10 2 kV Fuse 1 6 A 250 V 20 mm Fuse Holder 20 mm Panel Mount Tie Cable 3 6 x 142 mm Washer M4 Int Shakp SZP Nut 8 32 UNC Terminal Washer Terminal Washer Terminal Large Washer M3 Int Shakp SZP Nut Full M8 SZP Screw M3 x 6 POSICSK SZP Tie Cable 2 5 x 115 mm Tie Holder Screw M3 x 8 POZIPAN SEMS Circuit Board Support Terminal Insulator Terminal Base Terminal Low Thermal Black Terminal Low Thermal Red Terminal Low Thermal Blue Ferrite 26 x 14 x 11 8680 nF Cable Assembly Rear Input 8 wires w terminals Fluke Part No 2399180 2397993 1582072 2398399 2398161 2398256 850334 859939 613606 2398239 2398288 2398189 2398177 2398335 2398200 2398364 894183 885459 886379 886382 886366 2398386 2398106 Tot Qty 220 100 9 W 09n1nD 09 909 0909 A A A wy Notes List of Replaceable Parts 5 Parts Lists
40. FLUKE 8508A Reference 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 Warranty Each Fluke product is warranted to be free from defects in material and workmanship under normal use and service The warranty period is one year and begins on the date of shipment Parts product repairs and services are warranted for 90 days This warranty extends only to the original buyer or end user customer of a Fluke authorized reseller and does not apply to fuses disposable batteries or to any product which in Fluke s opinion has been misused altered neglected contaminated or damaged by accident or abnormal conditions of operation or handling Fluke warrants that software will operate substantially in accordance with its functional specifications for 90 days and that it has been properly recorded on non defective media Fluke does not warrant that software will be error free or operate without interruption Fluke authorized resellers shall extend this warranty on new and unused products to end user customers only but have no authority to extend a greater or different warranty on behalf of Fluke Warranty support is available only if product is purchased through a Fluke authorized sales outlet or Buyer has paid the applicable international price Fluke reserves the right to i
41. G BUT NOT LIMITED TO ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE FLUKE SHALL NOT BE LIABLE FOR ANY SPECIAL INDIRECT INCIDENTAL OR CONSEQUENTIAL DAMAGES OR LOSSES INCLUDING LOSS OF DATA ARISING FROM ANY CAUSE OR THEORY Since some countries or states do not allow limitation of the term of an implied warranty or exclusion or limitation of incidental or consequential damages the limitations and exclusions of this warranty may not apply to every buyer If any provision of this Warranty is held invalid or unenforceable by a court or other decision maker of competent jurisdiction such holding will not affect the validity or enforceability of any other provision Fluke Corporation Fluke Europe B V P O Box 9090 P O Box 1186 Everett WA 98206 9090 5602 BD Eindhoven U S A The Netherlands 11 99 To register your product online visit register fluke com Table of Contents Chapter Title 1 Introduction and Specifications eren Introduction sis e UU FH Rr HR REM eR ES Safety Consideratioms i cccscetsescsdevscsadsaassacesdeavaedcedescetassnteduadoasecdaseaadechtescadde SVIBDOJS ie ii rte Ro E EE dessa aa deoasdoadcaaseosbicbavageate Service Informatie i redi t PIRE ERE OPENS RA PR QU PEERS NR OE Pe PARES Howto Contact Tl ke rente t ptas rere e E eS PP eR P SER ard SPCCHIGAUIONS icc tete aet eae ie eni e guo ee Re ee TRE e eR Te e Rae ke ta enn ete ad Gene
42. Hz Range Gain HF 10V 60 kHz 200 V Zero 0 5 Range 1V 1 kHz Range Gain LF 100 V 1 kHz Range Gain HF 100 V 60 kHz 1000 v Zero 0 5 Range 5V 1 kHz Range Gain LF 500 V 1 kHz Range Gain HF 500 V 30 kHz 1 1000V range Gain calibrations may be performed at voltages above 500V The 1000V range Gain and Zero calbrations should be performed together with the Zero cal performed at 1 of the nominal value used for Gain The procedure assumes the user has knowledge of the actual output value of the calibrator at each point 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 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 the range LF and HF gain points from the applied signal frequency 1 Onthe Multimeter select the required Range On the Calibrator select Output Voltage and Frequency Operate On the Multimeter Press CAL to revert to CALIBRATION menu Select Set on the CALIBRATION menu ph ce ID 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 C
43. Input Select AC Preamp A1 DC PCA Input Signal Bus Internal Bus Range Selection DC AMP Chopper Stabilized eo A o o xx 3 a DC Preamp In guard Power Supplies Internal 250 VAC Range Switched Reference 45V 48V Precision Shunts 15 V 8V 36 V Input Select Out guard A4 Digital PCA Out Guard Power Supply 45V 48V 17 V EE Power C Serial Interface IEEE GPIP Rear Panel Keyboard and to M IEEE 488 Display Memory Serial GPIB Switching Relays Relay Drivers Input Signal EJ Relay Control and Optically Isolated COCOCOCOCOSCOCOCS UICC ttt Oe A6 Rear Input A5 Bezel Assembly and Assembly A5A1 Display PCA avw003f eps Figure 2 1 8508A Functional Block Diagram 2 4 Theory of Operation 2 Overall Functional Description A 16 pin cable W3 enables serial control and measurement data to move between the A4 Digital PCA and the A1 DC PCA Opto isolators on the A1 DC PCA optically isolate the external control and display circuits of the Multimeter from the measurement circuits This isolation minimizes problems associated with noise and current loops in the measurement circuits Throughout this chapter this isolation is referred to as in guard measurement circuits a
44. MPLE key will initiate a calibration operation and permanently alter the Multimeter s calibration state To avoid accidental mis calibration do not attempt to operate the Multimeter in External Trigger mode from the front panel when in Cal and only press the SAMPLE key when a calibration operation is intended to be performed Table 3 2 Calibration Sequence Enable Calibration Enter Cal mode General Sequence for Full Multimeter Calibration 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 Gains and Range HF Gains 200 mV to 1 kV Ranges Ohms Range Zeros and Range Gains Ohms 2 Q to 2 GO Ranges then Lol Ohms TruQ 2 Q to 20 kQ Ranges then Lol TruQ HiVQ 20 MQ to 20 GQ Ranges DCI Range Zeros and Range Gains 200 pA to 20 A Ranges ACI Range Zeros and Range Gains 200 pA to 20 A Ranges Frequency Frequency counter cal at 1 MHz Exit Cal mode NV input offsets Quit the CALIBRATION menu Front amp rear non volatile input offset adjustments DCV Ohms TruQ HiVQ including Lol 2 amp 4 wire Set CAL DUE Set the date for the next external calibration Disable Calibration Set rear panel calibration switch to DISABLE 1 To meet user s need just one range on one function can be calibrated Interc
45. Multimeter s operation by measuring a known voltage before and after using it Do not use the Multimeter if it operates abnormally Protection may be impaired If in doubt have the Multimeter serviced Whenever it is likely that safety protection has been impaired make the Multimeter inoperative and secure it against any unintended operation Have the Multimeter serviced only by qualified service personnel Do not apply 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 power source Never operate the Multimeter with the cover removed or the case open Use caution when working with voltages above 30 V ac rms 42 V ac peak or 42 V dc These voltages pose a shock hazard Use only the replacement fuse s specified by the manual Use the proper terminals function and range for your measurements Do not operate the Multimeter around explosive gas vapor or dust When using probes keep your fingers behind the finger guards When making electrical connections connect the common test lead before connecting the live test lead when disconnecting disconnect the live test lead before disconne
46. NUS senises ee e EEA EREE Accessing the Calibration Menus and Calibration Mode Calibration Menu sess enne enr enne enn enne SET VALUE MGnU coco ten i epe nern nieht SPOT CAL Mei rasen neben SPOT 1 to 6 RMS MenUs eerte tede b nee erar eroe eo as SPOT FREQUENCY 1 to 6 Menu sees Special Calibration rettet tie or ee kenne SPCL MEDU MN ILES SER sf Men i iier ipeeses re test d rre E decr p eU e HE REPOS Iso Non volatile input offset compensation essen Routine Calibration ertet RE ree ee aee nen ee EERE Equipment Required for Calibration sse Preparing for Calibration ccccccccsccsseessecsseceneceseceseeeeeeseeeseeeeeseesseeseesseeeaaees Interconnectlons oer een mern sean there RUE E oue ADC Calibration ifie tico reat ett nennen o ea onte epi ees ner DE Voltage Calbration eere erret PR ete pr ete tese rds AC Voltage Calibration nennen nnne Resistance Calibration cscccssseessesssecssesscesetersecescesaccosenstecodscodecsentsondeserdencess DC Current Calibration sesssesssessseenseenneennnennennennnennnnnnnnnnenne nn enne ernennen AC Current Calibration su E RE T Frequency Calibration isisisi sn Exit From Calibration Mode and Non Volatile Input Offset Adjustment Cal Due Date Entry and Calibration Mode Disable sss ACV Spot Frequency Cal
47. OPEN EDGE CONNECTOR EXCEPT AT STATIC FREE WORK STATION PLACING SHORTING STRIPS ON EDGE CONNECTOR HELPS PROTECT INSTALLED S S DEVICES 6 DO NOT SLIDE S S DEVICES OVER ANY SURFACE C 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 7 AVOID PLASTIC VINYL AND STYROFOAM IN WORK AREA PORTIONS REPRINTED WITH PERMISSION FROM TEKTRONIX INC AND GERNER DYNAMICS POMONA DIV amp Dow Chemical Chapter 4 Maintenance Title Page tO DU CUO ss A 4 3 Access Procter 4 3 Ieri 4 3 Cabling and Wiring Connections essen 4 4 Removing the A1 DC PCA ae cecinere itane tm ae 4 5 Removing the A2 AC PCA actes cs empires gerne seen 4 6 Removing the A3 Ohms PCA sess 4 7 Removing the A4 Digital PCA ccc ceccceseceseceseceeeeeeeceeeeeeneesseeeseeeeeeneeetees 4 8 Removing the A5 Bezel Assembly 4 9 Removing the A5A1 Display PCA sese 4 10 Removing the A6 Rear Input Assembly sse 4 11 Fuse Replacement and Line Voltage Selection sss 14 12 Line Power Fuse Fl and Voltage Selection 4 12 Rear Input Current Fuse F2 Rear Inputs Option 14 13 SIME CE 14 13 SEHE T Est Barons 4 suis RI ero pM FERE URINE eee 14 13 F tal Err rs ER 14 16 EXecuti
48. REQUENCY 1 to 6 Menu Enter this menu by pressing Enter in the SPOT 1 to 6 RMS menu which also stores the RMS value keyed in during this menu The value in the SPOT FREQUENCY 1 to 6 menu is the measured frequency of the present calibration input signal SPOT FREGUEMCY nm _ Gait Use SAMPLE to initiate CAL oreration adj142f eps SPOT FREQUENCY n Menu Pressing the SAMPLE key causes the selected ACV range to be spot calibrated at the calibration signal frequency The frequency value is stored and can be viewed from the UTILITY menu Any subsequent measurement on this range whose frequency is within 3 6 Calibration and Verification 3 Calibration Menus 10 of the stored frequency is accuracy enhanced by reducing frequency response flatness errors Calibrate the spot at a new frequency To calibrate the spot at a new frequency change the input signal to the desired new frequency and press SAMPLE as before Git Reverts to the SPOT CAL menu with the original Spot calibration intact Special Calibration The SPCL menu provides alignment of the main ADC and calibration of the frequency counter It also allows the High Voltage Linearity Pre Calibration to be performed and a section of the Non Volatile memory to be cleared for test purposes These facilities are used in the factory for initial pre calibration processes they should not require access during the life of the Multimeter unless repairs have been carried ou
49. SH SKTHD BLK Screw M3 X 8 Pozipan Binding Post Brass NiPL Binding Head Brass NiPL Clip Cable Flat Ribbon Washer M3 INT SHAKP SZP Nut Full M8 SZP Washer M6 INT SHAKP SZP Nut Full 1 4 28 UNF BNP Nut Nylock M4 SZP Washer M4 Plain SZP Screw M3 X 6 Pozicsk Standoff M3 X 16 M F Nylon Screw M3 X 8 Pozicsk PCB Card Guide Bush Insulating 8 8 ID Black Hole Plug 5 8 Black Low Voltage Transformer Assembly Mains Transformer Assembly Cable Sig I P Assembly Cable Ribbon Assembly 16W Cable Ribbon DC DIG Assembly Cable Ribbon DC OHM Assembly Cable Ribbon DIG DS Assembly Wire 7 2 PTFE 1 kV Green Lead Kit PTFE Lead Kit Standard Fluke Part No 1988709 1988727 1988748 1988730 1605337 2398049 2398024 295105 2398200 102707 102889 2398320 2398239 2398288 2398263 2398301 2398295 2398242 2398189 2398221 2398192 2398312 2398347 2398358 2398036 2398060 2398008 2398013 2398072 2398085 2398097 2398150 1886203 2398911 Tot Qty BS Rose Se Pe dq e ok XO dq amp nox olx x ca nx N N 2a ny e242 424 4 un Ny oApo oan Notes 1 These are removed when the Rear Input Assembly is installed List of Replaceable Parts 5 Parts Lists Top View STICK OVER SMALL HOLES avw026f eps Figure 5 2 8508A C
50. alibration is complete when the Busy legend goes out and the calibrated measurement is displayed Note that HF gain calibrations are iterative and repeating the HF calibration may improve the result 7 On the Calibrator set Output to STANDBY On the Multimeter press ACV key to revert to the ranges menu 3 17 8508A Service Manual Resistance Calibration When calibrating the resistance function each of the resistance modes Normal Lol TruQ Tru Lol and HiVQ must be individually calibrated The following procedure assumes use of a multifunction calibrator and calibrates each resistance mode in turn range by range If individual standard resistors are used it may be more convenient to calibrate all the modes in turn for each resistance value to avoid connecting the same resistance standard several times during the calibration sequence A 1 GQ standard resistor provided in the 8508A 7000K calibration kit is used for ranges above 200 MQ as the highest resistance available from the 5720A calibrator is 100 MQ Refer to Table 3 5 for the resistance calibration points and sequence Table 3 5 Resistance Calibration Points and Sequence 8508A Range Modes Point Resistance 20 Normal Normal Lol Zero 0 Q TruQ TruQ Lol Range Gain 1Q 20 Q Normal Normal Lol Zero 02 TruQ TruQ Lol Range Gain 10 Q 200 Q Normal Normal Lol Zero 0 Q Tru TruQ Lol Range Gain 100 Q 2 kQ Normal Norma
51. ally 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 2 er 3 04 0 2 x gt 3 0 0 4 3 4 ppm of 10 V Second expressing the contributions in volts 3 0x 10 x 10 0 2x 10 x 20 43 4x 10 2 434 uV The 8508 is designed to provide accuracy and stability without the need for internal auto or self calibration routines which may otherwise compromise the continuity and traceability of measurement performance history To realise the full potential of the 8508A performance accepted metrology practices should be employed such as performing a zeroing or null operation to remove any offsets present in the measurement setup when making DC measurements The 8508A specifications assume that these methods are employed Absolute and Relative Specifications The Relative to Calibration Standards specifications describe the performance of the 8508A itself for the time periods and temperature range listed excluding the uncertainty of the standards used to perform calibration of the 8508A during manufacture The Absolute specifications include the uncertainty of the standards used to perform calibration of the 8508A at manufacture and may be used to determine the uncertainty of measurements made with the 8508A for periods up to year and over a temperature range of 5 C from calibration If the user has their 8508A
52. ance range zero calibrations in itt ce Srecial Special Cal is indicated on the main display The SPCL menu is displayed which allows pre calibration of the Multimeter calibration of the frequency counter and entry to other calibration utilities Fuit 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 SET WALUE Enter Quit adj139f eps SET VALUE Menu When this menu appears it shows the nominal calibration point value allowing the user to enter the true output value of the calibration standard at the point to be calibrated The keyboard is activated locking out all other keys The Set value is entered in exponential format expressed in Volts Amps or Ohms and must be above 20 of range 40 on the 1000V DCV and ACV ranges The SAMPLE key has no effect until the Set value is stored by pressing the Enter key The Multimeter always chooses the most recently stored Set value when calibrating Set is not available for DCV DCI and Resistance range zero calibrations A Caution Enter The new value is stored and the keyboard is de activated The set value remains on the dot matrix display for comparison with the reading on the main display after the SAMPLE key has been pre
53. and regulators located on the Al DC PCA These T1 supplies provide the following in guard operating voltages 5V dc regulated 8 V dc un regulated 15 V dc regulated 36 V dc regulated 250 Vac All of the in guard PCAs use these in guard voltages with the exception of the 250 V ac which goes directly to the A3 Ohms PCA where it is rectified and filtered for use in making the high voltage ohms measurements The 250 V dc supply is active only when the High Voltage Ohms function is selected A few other in guard voltages which are uniquely developed and used on the A3 Ohms PCA include 5 V 15 V 6 V and 5 5 V The in guard voltages on the Al DC PCA are the original source driving all of these uniquely developed voltages on the A3 Ohms PCA Theory of Operation 2 Overall Functional Description J401 250 V ac to Ohms 15 V dc 15 V dc 18 V dc 36 V dc Out guard Voltages 17 V regulator 8 V regulator 5 V regulator avw004f eps Figure 2 2 Power Supplies Simplified Block Diagram 8508A Service Manual 2 8 Chapter 3 Calibration and Verification Title Page Introduction Calibration OVerview Em Calibration Interval and Performance cccccesssessceeeeeeeeeeseeeseesecsseceeceeenseenes Calibration Points sensible be baleniliehektensande Non Nominal Values enne Enabling Access to Calibration Mode sse Calibration ME
54. calibrated with different uncertainties the Relative specifications can be combined with the uncertainties applicable to that calibration to determine the effective absolute uncertainty following that calibration 8508A Service Manual Applying User s Calibration Uncertainties When the 8508A is calibrated by another laboratory the uncertainties of the calibration standards used may be applied by combining those uncertainties with the 8508A s Relative to Standards specifications The applicable calibration uncertainties and the 85084 relative specifications must both be expressed at the same confidence level and be combined in a RSS Root Sum Square summation Accepted metrology practice mandates that calibration uncertainties are stated at 95 Check the applicable calibration uncertainties are stated at 95 and then combine them with the 8508A 95 Relative specifications For example if the 8508A is calibrated at 10 V DC with an uncertainty of 1 5 ppm at 95 The absolute uncertainty at 10 V for a period of 90 days and 1 C from calibration is 2 f14 02x2 2 3 ppm of 10 V Operating and Calibration Temperature Ranges As a metrology tool the 8508A will commonly be used in a calibration laboratory where the temperature would be controlled to 1 C and the 8508A 1 C specifications are applicable to those situations The majority of electrical calibration laboratories operate at a nominal temperature of 23 C the temperat
55. can be read destructively as LIFO by the Common query command DDQ In local mode operations the DDE status is checked at the end of the operation e g Cal Zero Test If true an error has occurred and the content of the last entry in the queue is displayed on the front panel If both bus and front panel users attempt to read the queue concurrently the error data is read out destructively on a first come first served basis Thus one of the users cannot read the data on one interface as it has already been destroyed by reading on the other This difficulty should be solved by suitable application programming to avoid the possibility of a double readout Ideally the IEEE 488 interface should set the instrument into REMS or RWLS to prevent confusion The bus can ignore the queue but the front panel user will have to read it to continue There are three categories of Device Dependant Errors Correction Errors Corruption Errors and Miscellaneous Errors The errors that may occur in each category are described in the Table 4 9 4 19 8508A Service Manual Table 4 9 Device Dependent Errors Correction Errors z000 Error During Zero Cal The input signal was outside Zero 1 of Full Range z ni Error During Gain Cal The input signal was outside full range 10 of full range 2002 Error During Gain Cal The input signal was outside full range 10 of full range 2 003 Er
56. cker 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 AF1 Fuse 630 mA 250V 20mm TH 1582145 1 AF1 Fuse 1 6A 250V 20mm F 1582072 1 AF1 Fuse 1 25A 250V 20mm TH 1582150 1 Mains Lead Power Cord 1 Not shown Mains Lead IEC TO CEE7 7 769422 Mains Lead IEC UK 5A 2m 769455 Mains Lead IEC AUS NZ 10A 2 5m 658641 Mains Lead IEC USA JAPAN 284174 Mains Lead IEC SWISS 10A 2 5m 769448 Mains Lead IEC INDIA 10A 2 5m 782771 SPRT 25R5 200 TO 660 DEG C 1656430 PRT 100R 200 TO 660 DEG C 1654000 Users Manual 8508A 1673798 1 Not shown Service Manual 8508A sold separately 2150128 Not shown Manual Set CD PDF files includes Service Manual 2150143 1 Not shown 5 4 List of Replaceable Parts Parts Lists MP1 Figure 5 1 8508A Final Assembly avw025 eps 5 8508A Service Manual 5 6 Table 5 2 8508A Chassis Assembly Reference Designator At A2 A3 A4 A5 A6 A401 H1 H2 H3 H4 H5 H6 H7 H8 H9 H10 H11 H12 H13 H14 MP1 MP3 MP2 Ti T2 wi w2 w3 wa W5 W6 W7 Description DC PCA AC PCA Ohms PCA Digital PCA Bezel Assembly Rear Input Assembly optional Reference Module POS Assembly Screw 8 32 X 3 8
57. connectors from the rear edge of the A3 Ohms PCA b Remove the one philips screws from the A3 Ohms PCA c Slide the A3 Ohms PCA toward the rear of the unit about 4 inch d Liftthe A3 Ohms PCA and free the two hardwired cables before removing it from the unit P avw012f eps Figure 4 4 Removing the A3 Ohms PCA 4 7 8508A Service Manual Removing the A4 Digital PCA Use the following procedure to remove the A4 Digital PCA See Figure 4 5 l 2 4 8 Position the unit on the work surface so it 1s top side up Remove both rear feet 1 a Remove the three hex screws from each foot b Ifthe feet are still in place pull them from the unit Remove the top and bottom covers 2X3 a Remove one philips screw at rear of each cover b Slide the covers toward the back of the unit and lift them off Remove the Rear Panel 4 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 Pullthe gray sheet metal portion of the rear panel away from the unit Set the unit on its side and remove the screw holding the input sense connector group to the chassis 5 Return the unit to its original position Disconnect the five cable connectors from the A4 Digital PCA Free the A4 Digital PCA by sliding it out the rear of the chassis 6 avw013f eps
58. cting the common test lead Disconnect circuit power and discharge all high voltage capacitors before testing resistance continuity diodes or capacitance Before measuring current check the Multimeter s fuses and turn OFF power to the circuit before connecting the Multimeter to the circuit When servicing the Multimeter use only specified replacement parts 1 4 Introduction and Specifications 1 Safety Considerations Symbols The following safety and electrical symbols may be used on the Multimeter or in this manual Risk of danger Power ON OFF Important information See manual Earth ground AC Alternating Current CAT IEC 61010 Overvoltage installation or measurement Category Hazardous voltage Voltage 30 V dc or ac peak might be present DC Direct Current Fuse AC or DC Alternating or Direct Current recycling information Potentially hazardous voltage Double insulated Do not dispose of this product as unsorted municipal waste Go to Fluke s website for mmm 8508A Service Manual Service Information In case of difficulty within the 1 year Warranty period return the Multimeter to a Fluke Service Center for Warranty repair For out of Warranty repair contact a Fluke Service Center for a cost estimate This service manual provides instructions for verification of performance calibration and maintenance If you choose to repair a malfunction information in this manual can hel
59. ction above regarding the impact of calibration uncertainties and use of other specifications 2 Ranges require separate input zero operation in each resistance mode DC Current Checks Equipment Configuration 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 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 200uA range and working up to the 20A range as listed in Table 3 11 An input zero operation is performed on each Multimeter range prior to performing the range verification measurements with the calibrator set to zero by range locking the calibrator in the range from which the output will be obtained 1 Select the required Multimeter range 2 On the calibrator set the output to zero Select OPERATE 3 On the Multimeter press the INPUT key and select Zero Rng to initiate the zeroing operation The Busy legend will appear and then extinguish when the zero operation has completed 4 On the calibrator select the value required for verification in the positive polarity 5 Note the Multimeter s reading Compare the result wit
60. ctly 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 preamplifier and an rms to dc converter The output of the rms to dc converter is a dc voltage proportional to the true rms value of the input signal The multiplexer on the A1 DC PCA receives the dc voltage and routes it to the ADC Analog to Digital Converter which in turn sends the digital results to the opto isolators The opto isolators couple the digital data to the A4 Digital PCA for access by the display and GPIB The A1 DC PCA provides the configuration control required to connect the ac input signal to the A2 AC PCA For ac voltage measurements the input signal is routed in much the same manner as a dc measurement signal For ac current measurements the ac input current is routed through the same set of current shunts used to make dc current measurements To measure the ac current the A2 AC PCA measures the voltage drop across the shunt and sends the results to the A4 Digital PCA as when making an ac voltage measurement The A3 Ohms PCA performs 2 wire 4 wire high voltage and ratio measurements All of these measurements derive the unknown resistance value by passing a constant stimulus current through the unknown resistor and measuring the resulting voltage drop acro
61. ctric shock when performing the following calibration procedures e Never touch any lead or terminal unless you are absolutely certain that no dangerous voltage is present e Make sure that signal leads are in a safe condition before you handle them in any way Initial Setup l 2 3 Press the DCI key select the 200 uA range Press the CONFIG key Select Filt 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 Reselect DCI 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 Ensure that the calibrator output is set to STANDBY and configured for Internal Guard EXT GRD is deselected Connect the Calibrator to the Multimeter as shown above Range Zero and Gain Calibration Procedure After the initial setup and connecting up use the following procedure to calibrate range zero then positive and negative range gains on all DCI ranges Just one range can be calibrated if required but for a full calibration start with the 200 uA range and work up to the 20A range as shown in Table 3 6 3 25 8508A Service Manual Zero Point 1 3 26 Table 3 6 DC Current Calibration Points and Sequence 8508A Range Point Current 200 uA Zero 0 uA Range Gain
62. does not appear on the left hand display Ensure that the calibrator output is set to STANDBY and configured for Internal Guard EXT GRD is deselected Connect the Calibrator to the Multimeter as shown above Range Zero and LF Gain Calibration Procedure Using the following procedure to calibrate range zero then range gain on all ACI ranges at the currents and frequencies detailed in Table 3 7 Just one range can be calibrated 1f required but for a full calibration start with the 200 uA range and work up to the 20A range 3 27 8508A Service Manual 3 28 Table 3 7 AC Current Calibration Points and Sequence 8508A Range Point Current Frequency 200 uA Zero 5 6 Range 10 uA 300 Hz Range Gain 100 uA 300 Hz 2mA Zero 0 5 Range 10 uA 300 Hz Range Gain 1 mA 300 Hz 20 mA Zero 0 5 Range 100 pA 300 Hz Range Gain 10 mA 300 Hz 200 mA Zero 5 Range 10 mA 300 Hz Range Gain 100 mA 300 Hz 2A Zero 5 Range 100 mA 300 Hz Range Gain 1A 300 Hz 20A Zero 5 Range 1A 300 Hz Range Gain 10A 300 Hz The procedure assumes the user has knowledge of the actual output value of the calibrator at each point 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 point If the calibrator output is considered to be exactly nominal use of the Set feature 1s not required al
63. e 9599 Uncertainty Relative to Cal Stds Absolute Uncertainties Range Full Scale Mode ppm Reading ppm Range 24 hour 90 day 365 day 365 day 365 day TCal 1 C TCal 1 C TCal 1 C TCal 1 C TCal 5 C 95 Confidence Level 20 1 999 900 00 Normal 5 0 2 0 8 0 2 0 10 2 0 15 2 0 17 2 0 200 19 999 000 0 Normal 2 5 0 7 4 5 0 7 7 0 0 7 9 0 0 7 9 5 0 7 200 Q 199 990 000 Normal 1 5 0 25 4 0 0 25 7 0 0 25 7 5 4 0 25 8 0 0 25 2 kQ 1 999 900 00 Normal 1 0 0 25 3 5 4 0 25 7 0 0 25 7 5 4 0 25 8 0 0 25 20 KQ 19 999 000 0 Normal 1 0 0 25 3 5 0 25 7 0 0 25 7 5 0 25 8 0 0 25 200 kQ 199 990 000 Normal 1 0 0 25 3 5 0 25 7 0 0 25 7 5 0 25 8 0 0 25 2MQ 1 999 900 00 Normal 2 0 0 5 4 0 0 5 7 0 0 5 8 5 0 5 9 0 0 5 20 MO 19 999 000 0 Normal 3 5 5 0 6 0 4 5 0 9 0 5 0 154 5 0 20 5 0 200 MQ 199 990 000 Normal 20 50 25 4 50 30 50 60 50 120 50 2 GQ 1 999 900 00 Normal 250 500 350 500 500 500 525 500 1510 500 20 1 999 900 00 Lo Current 5 0 2 0 8 0 2 0 10 2 0 15 2 0 17 2 0 200 19 999 000 0 Lo Current 2 5 0 7 4 5 0 7 7 0 0 7 9 0 0 7 9 5 0 7 200 Q 199 990 000 Lo Current 2 5 0 7 5 0 0 7 7 0 0 7 7 5 4 0 7 8 0 0 7 2 kQ 1 999 900 00 Lo Current 2 5 0 7 5 0 0 7 7 0 0 7 7 5 4 0 7 8 0 0 7 20 KQ 19 999 000 0 Lo Current 2 5 0 7 5 0 0 7 7 0 0 7 7 5 4 0 7 8 0 0 7 200 kQ 199 990 000 Lo Current 5 0 4 0 5 6 5 4 0 5 7 0 4 0 5 7 5 4 0 5 8 0 4 0 5 2 MQ 1 999 9
64. e compensation by using one of the following operations 1 Power the Multimeter down 2 Press the CLEAR key and make any of the selections from the CLEAR menu 3 Press the CAL key and entering CAL mode 4 Usethe corresponding IEEE 488 commands Routine Calibration The 8508A Digital Reference Multimeter offers state of the art performance This procedure is intended as a guide for qualified metrology personnel who have access to a standards laboratory with equipment available to support an Multimeter of this level of accuracy It reflects the calibration process used by Fluke to perform Multimeter calibration implemented in an automated system but as a manual procedure for users to follow The procedure is based on the following assumptions 1 Users are familiar with relevant best measurement 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 calibration references of adequate traceable uncertainty are available in this case a Fluke 5720A calibrator and 5725A amplifier used with an 8508A 7000 Calibration Kit The procedure assumes the user is able to calibrate and characterize the calibration sta
65. e Input Offset Adjustment Cal Due Date Entry and Calibration Mode Disable ssssss ACV Spot Frequency Calibration Performance Verification eter A ehe e ehren Io Pe ees Equipment Requirements essere nere Interconnections eee cent edicere i nen en FERAE Ea EER Applicable Verification Tolerance and Conditions sss lucpriciloIm MEE pennis cm E AC Voltage Checks ise cett edite true Cen kanns hin R sistance CHECKS ss eee nein kenn krachen DC Current Checks 2 et recette ol shed Eph e eb ERN nina AC Current Checks eiecti leunnendenassin Frequency Checks ne a aaa 4 Maintenance u u aaa aan nen daran nenne Introduction mt PCOS 5 fure ME Before bebrni e Cabling and Wiring Connections sese Removing the Al DC PCA sssssssesseeee ener enne nennen nenne Removing the A2 AC PCA ssssssssseseeee ener nennen nenne Removing the A3 Ohms PCA sssssssseseeeeeeeeneen nennen Removing the A4 Digital PCA ceenennennsnnnsnnnennnennennnneenn nenne Contents continued Removing the A5 Bezel Assembly sees 4 9 Removing the ASA1 Display PCA sess 4 10 Removing the A6 Rear Input Assembly sse 4 11 Fuse Replacement and Line Voltage Selection eenneneneennen 14 12 Line Power Fuse Fl and Voltage Selection
66. e Multimeter houses the line power fuse F1 See Figure 4 9 A fuse tray to the right of the module serves as a fuse holder and a line voltage selection device A small window on the fuse tray shows the currently selected line voltage 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 line voltage shows in the fuse tray window 3 As necessary remove and replace the fuse with one that corresponds to the selected line voltage See Table 4 1 4 Slide the fuse tray back into the power input and voltage selection module and secure it by firmly pressing it into place AN SAFETY WARNING 1 LINE VOLTAGE FUsE 5x 20mm LEADS BEFORE REMOVING COVERS SELECTION IEC 127 2 FOR CONTINUED PROTECTION AGAINST ROTECTIVE CONDUCTOR MUST BE CONNECTED 115 TZS AN 230V Y EARTH GROUND 230 T630 mAH 250V A 250V FUSE OF THE CORRECT RATING POWER INPUT 80 VA MAX 50 60 Hz 4 READ THE OPERATORS MANUAL BEFORE USE adj019f eps Figure 4 9 Rear Panel Power Input Fuse and line Power Locations Table 4 1 Power In
67. e anti static techniques after the covers are removed from the Multimeter Do not unnecessarily touch any part of the PCAs or straighten component positions on the PCAs 4 3 8508A Service Manual Cabling and Wiring Connections To help avoid making incorrect cable connections during reassembly refer to the internal wiring and cabling diagram shown in Figure 4 1 FRONT ps102 E A5A1 Display PCA HO oO W6 16 w5 16 KH A1 DC PCA top A2 AC PCA PL30 p Black E106 Brown E105 Red E103 Green E104 Orange E101 Yellow E102 e e A3 Ohms PCA and Voltage Selection Sa 4 4 avw032f eps Figure 4 1 Internal Wiring and Cabling Diagram Maintenance 4 Access Procedures Removing the A1 DC PCA Use the following procedure to remove the A1 DC PCA See Figure 4 2 l 2 Position the unit on the work surface so it is bottom side up Remove both rear feet 1 a Remove the three hex screws from each foot b Ifthe feet are still in place pull them from the unit Remove the bottom cover 2 a Remove the one philips screw at rear of the bottom cover
68. e as DC Voltage Filter In but Temperature Temperature Readout 11 2 3 Introduction and Specifications Specifications Absolute Resistance Typical Equivalent Temperature Measurement Uncertainty Measurement Uncertaint i Resistance Range 365 day Tcal 1 C y Probe Type ae Resistance Accuracy ppm Reading mQ C Q x C 95 Confidence Level 0 199 990 000 Q 75 0 14 25 Q PRT SPRT 200 5 0 0085 25 Q PRT SPRT 0 25 0 0035 25 Q PRT SPRT 660 84 0 0025 100 Q PRT SPRT 200 20 0 0035 100 Q PRT SPRT 0 100 0 0025 100 Q PRT SPRT 232 185 0 0020 200 1999 900 00 Q 7 5 0 5 100 Q PRT SPRT 400 250 0 0025 99 Confidence Level 0 199 990 000 Q 9 5 0 18 25 Q PRT SPRT 200 5 0 0010 25 Q PRT SPRT 0 25 0 0040 25 Q PRT SPRT 660 84 0 0025 100 Q PRT SPRT 200 20 0 0040 100 Q PRT SPRT 0 100 0 0025 100 Q PRT SPRT 232 185 0 0020 200 1999 900 00 2 9 5 0 6 100 Q PRT SPRT 400 250 0 0025 Temperature Readout Secondary Specifications Resistance Measurement Uncertainty Resistance Range Transfer Uncertainty 2 Wire 3 Wire Temp Coeff ppm Reading C 20 Minute 1 C Adder Adder 5 C 15 C ppm Reading mQ Q Q 15 C 30 C 30 C 40 C 0 199 990 000 Q 0 8 0 14 0 1 0 005 0 6 1 0 200 1999 900 00 Q 0 2 0 5 0 1 0 005 0 5 0 8 Temperature Range Linearization Current Source 4 wi
69. ecifications 90 day or 365 day combined with the calibration uncertainties applicable to the previous calibration RSS summation is recommended with calibration uncertainties also expressed at 99 confidence level The Multimeter s temperature coefficient specifications should also be applied if the temperature at verification is outside the range applicable to the Multimeter s specifications Refer to Chapter 1 for further information on applying specifications and combining uncertainties 3 32 Calibration and Verification 3 Performance Verification Fluke guarantees the Multimeter s performance verification using specifications stated to 99 confidence level Preparation 1 Allow the Multimeter to warm up under power in the specified environment for at least 4 hours 2 Press the CLEAR key select Pwr Up Dflt to restore the power up default configuration and display the DCV menu 3 Press the Test key and select Std to initiate a selftest Should the Multimeter fail contact your local authorized Service Center ensuring that the full circumstances of the failure are reported DC Voltage Checks AA Warning The Calibrator can deliver a lethal electric shock To avoid electric shock when performing the following calibration procedures e Never touch any lead or terminal unless you are absolutely certain that no dangerous voltage is present e Make sure that signal leads are in a safe condition before you handle
70. eeseeenseeeecsseeseeeeeeseeeeeneeenes Calibration Points ssenaristi een Non Nominal Values eiit ont eR e HI RETE NH ETIN TIRE E Enabling Access to Calibration Mode sss Calibration Men s teet ette sa egeta rok ead ees eb Po E Ee epp ee Ponens eoo este Accessing the Calibration Menus and Calibration Mode cli entend SET VALUE MEDU i 3 coa cire eed ere eo te dettes esee denen ee no rite SPOT e uum RS SPOT 1 to 6 RMS Menus isssesseseeeeeeeereneren nennen nennen nennen nnne SPOT FREQUENCY 1 to 6 Menu sess Special Calibration sess eee nnne SPECE mS SER TI P H M Hylin Menu iet steterit esset ie piede eed A A A de obe TEES PR SURE Non volatile input offset compensation esses Routine Calibration d rettet des be ei nee Equipment Required for Calibration seseeeenne Preparing for Calibration ioni er Interconnections sses ee eessen enne ener enne enne nennen nennen ADC Calibration itte irt t rs eo sa Pre bo eros tbe ans ores DC Voltage Calibration sssssssssesseseereee eene AC Voltage Cahbration ure doe oH EHE DEP ENTE E Resistance Calibration sss ener ener DG Current Calibration oie deti rd t eerie eerta de AC Current Calibration sees Frequency Calibration ER ii ette He eto peto evlecbaneveds Exit From Calibration Mode and Non Volatil
71. end goes out and the calibrated measurement is displayed On the Calibrator set STANDBY 7 Press the Q key to revert to the ranges menu Lolg2 Mode Calibration 1 Press the Q key and select the 2 Q range 2 Press the CONFIG key and select Filt Lol and 4wQ 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 Lol mode For the 2 GQ range use the 1 GQ standard resistor in place of the calibrator Just one range can be calibrated if required but for a full calibration start with the 2 Q range and work up to the 2 GQ range Note that EX SNS 4 wire is not available on the 5720A 100 MQ range and the 8508 7000K 1 GQ standard resistor is used as a 2 wire device with the calibrator 2 wire resistance zero used for the corresponding zero points 4WQ is deselected on the Multimeter when calibrating the 200 MQ and 2 GQ range range zero and range gain points On each range the Multimeter automatically recognizes the appropriate value as range zero or range gain from the applied resistance value Note It is unlikely that the resistance standard will be at exactly the nominal value required The Set feature allows 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 requi
72. er Functional block diagrams supplement the text when appropriate In addition to providing a conceptual overview of the Multimeter s operation the descriptions are helpful for troubleshooting and isolating problems to a board level Reference Designators are used throughout this chapter to identify the major Printed Circuit Assemblies PCAs used in the Multimeter These reference designators also appear in the List of Repaceable Parts Chapter 5 to simplify the process of purchasing replacement modules and PCAs Overall Functional Description Main Assemblies Refer to the functional block diagram shown in Figure 2 1 while reading this description In addition to identifying all of the assemblies contained in the Multimuter this diagram provides a functional view of the data flow between the assemblies Assembly interconnections and cable identification is detailed in chapter 4 Maintenance The following list identifies the six major assemblies contained in the Multimeter and includes a description of the basic functions each assembly performs A1 DC PCA Optical isolation measurement configuration V dc I dc and I ac measurements A2 AC PCA True rms measurement 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 D
73. ero output and Operate On the Multimeter press CAL to enter the CALIBRATION menu Press SAMPLE to initiate the calibration operation Calibration is complete when the Busy legend goes out and the calibrated measurement is displayed 8508A Service Manual Range Gain Points 1 2 3 4 G G9 E ON On the Calibrator select the positive Range Gain point Output value On the Multimeter Press CAL to revert to CALIBRATION menu Select Set on the CALIBRATION menu Use the numeric keys with the SET VALUE menu to key in the true output value of the calibrator at the range gain value then press Enter Press SAMPLE to initiate the calibration operation Calibration is complete when the Busy legend goes out and the calibrated measurement is displayed On the Calibrator select the negative Range Gain point Output value Repeat steps 3 to 5 above to calibrate the negative Range gain point On the Calibrator set Standby Press the DCV key to revert to the ranges menu AC Voltage Calibration AA Warning The Calibrator can deliver a lethal electric shock To avoid electric shock when performing the following calibration procedures e Never touch any lead or terminal unless you are absolutely certain that no dangerous voltage is present e Make sure that signal leads are in a safe condition before you handle them in any way Initial Setup and Connections l 2 Press the ACV key select the 200 mV range Press t
74. est Table 4 8 Execution Errors 100g EXE queue empty when recalled i z4 Illegal Range Input Combination i ni Option not installed 1025 Auto not available in Tru ratio 1002 Calibration disabled i uz amp Probe identity unrecognized 1003 Input Zero not allowed in Scan i z Input Zero not allowed in PRT i r Data entry error i za Only allowed in Voltage function 1003 Must be in AC Function i z3 Scan modes not allowed in PRT 1010 Divide by zero not allowed 1030 Scan modes not allowed in ACI DCI 1012 No more errors in list 1031 4wV not available via rear input 1013 Data out of limit 1032 Input Zero not allowed in Cal i id Illegal Range Function combination 1233 Calibration not allowed in PRT 1015 Command allowed only in Remote 1034 PRT Ceof Limit a b c a b c i i amp e Not in Special Calibration 1035 Cannot edit the default PRT 1021 Test not allowed when Cal enabled 1038 Block or Rolling average required Device Dependant Errors Device dependent errors are associated mainly with test and calibration operations A Device Dependent Error is generated ifthe device detects an internal 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
75. est No 93 Err 2931 P028 100V AC Range 9 78V DC Input Checks at PreAmp Output Test No 94 Err 2941 P029 1000V AC Range Zero Input Check 2942 raw Test No 95 Err 2951 P030 1000V AC Range 9 78V DC Input Checks at PreAmp Output Test No 96 Err 2961 P031 1000V AC Range 9 78V DC Input Checks at PreAmp Output 4 15 8508A Service Manual Fatal Errors 4 16 Fatal errors are reported only via the front panel display These messages are all coded as 9000 series faults Each of the fatal errors that might occur are identified in the following paragraphs When a fatal error occurs the processor halts the operation of the multimeter Cycling the power off and on may clear the message Howerver fatal errors are generally caused by hardware or software faults which require repair by at a Fluke Service Center S000 System Kernel Fault Addr id This error is generated for system queue errors stack overflows etc See Table 4 4 for descriptions of 9000 system kernel fault errors Table 4 4 9000 System Kernel Fault Errors id Fault n user stack overwritten addr user stack pointer address ni activity at head of queue not current addr address of queue nz current activity not at head of queue addr address of queue a001 Eun Time System Error This error is detected and generated by the Pascal run time system support e g variable out of range a002 Unexrected Excertion Addr id See
76. f performed this operation must take place after the 2 GO range gain point calibration to avoid the automatic process overwriting the result Voltages of approximately 200V will be developed across the resistance standard at full scale ensure the resistance standards used are suitable for operation at these voltages Note that EX SNS 4 wire is not available on the 5720A 100 MQ range and the 8508 7000K 1 GQ standard resistor is used as a 2 wire device with the calibrator 2 wire resistance zero used for the corresponding zero points 4WQ is deselected on the Multimeter when calibrating the 200 MQ and 2 GQ range range zero and range gain points On each range the Multimeter automatically recognizes the appropriate value as range Zero or range gain from the applied resistance value Note It is unlikely that the resistance standard will be at exactly the nominal value required The Set feature allows 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 Onthe Multimeter select the required range 2 On the Calibrator select zero Q and Operate For the 200 MQ range and above de select Ex SNS on the calibrator and de select 4WQ on the Multimeter Alternatively if using a standard resistor connect the standard resistor for a 4 wire resistance zero On the
77. for verifying performance of the resistance function refer to the resistance measurements section of Chapter 3 Making 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 the Multimeter at the Fluke factory They are applicable to a verification performed within a period of 365 days from calibration and at a temperature within 1 C of the temperature at which calibration was performed 23 C for calibrations performed by Fluke It is recommended that these tolerances only be used for verification of the Multimeter following calibration by Fluke and if the above time period and temperature conditions are met No allowance has been made for the uncertainty of the equipment used for verification If the required conditions are met but the temperature lies within 5 C of factory calibration it is recommended that the user applies the 365 day Tcal 5 C Absolute specifications instead For other circumstances such as following calibration by another laboratory it is recommended that the user derive verification tolerances from the applicable Multimeter s 99 Confidence Level Relative to Standards sp
78. gram ccccsccesccessceseceeeeeeceeeeeeeeseeeeseeesseesseeeseeesaes 2 4 2 2 Power Supplies Simplified Block Diagram sese 5 3 3 1 Equipment Connections Required for Calibration eee EBEN 4 1 Internal Wiring and Cabling Diagram sese 4 4 4 3 Removing the A2 AC PCA ebenen 4 6 4 4 Removing the A3 Ohms PCA cecnssnsennseeneesnensnnnsnnnennnnnnnnsennsnse nn 4 7 4 5 Removing the A4 Digital PCA sessssssssseseeee enne 4 8 4 6 Removing the A5 Bezel Assembly 0 cccccccsseesseesseceteceseceseceseenseeneeeeeeeseneseneeenes 4 9 4 7 Removing the ASA1 Display PCA sssssseseeeeneeneen enne 4 10 4 8 Removing the A6 Rear Input Assembly cenenesneesneesnnesnensnnnnnnennens nenne 4 11 4 9 Rear Panel Power Input Fuse and line Power Locations 4 12 5 1 8508A Final Assembly sess ener enne enne nennen 5 2 8508A Chassis Assembly eee eere ese H t Ee Pret ede 5 3 A5 Bezel front panel Assembly ssssssssssseseeeeeeeeenenenens 5 4 Rear Input Assembly optional sesssssseseseeeeeeeenenren nennen vii 8508A Service Manual viii Chapter 1 Introduction and Specifications Title Page Introduction Safety Considerations enaesefe en eaae Qa eid ES ENEAN SYMIDOIS E Service Information ICD M e ER ERR re EE Ge EROR EUR How to Contac
79. h Errors id Fault U901 C pattern mismatch should be 00000001 00000000 if rear fitted i U901 B pattern mismatch should be 00010000 z U901 A pattern mismatch should be 10100100 U902 C pattern mismatch should be 00000000 Di U902_B pattern mismatch should be 00000000 s U902 A pattern mismatch should be 00000000 LIE U903_C pattern mismatch should be 00010101 oF U903_B pattern mismatch should be 01111111 a U903 A pattern mismatch should be 11111011 3007 Unknown Engine Ingtrpuction Addr id ici 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 set true in the Standard defined Event Status Byte and the error code number is appended to the Execution Error queue The error is associated with status reporting and the queue entries can be read destructively as LIFO by the Common query command EXQ There is no queue when execution errors occur during manual operation instead the description of the error is sent directly on the Menu display See Table 4 8 for descriptions of the execution errors 4 18 Maintenance Self T
80. h the allowable tolerance taking into account any known error from nominal of the calibrator for this output 3 40 Calibration and Verification 3 Performance Verification 6 Onthe calibrator select the value required for verification in the negative polarity 7 Note the Multimeter s reading Compare the result with the allowable tolerance taking into account any known error from nominal of the calibrator for this output Table 3 11 DC Current Verification Points and Sequence 8508A Range Current Tolerance 200 uA 0 uA Perform input zero operation to calibrator range locked zero output 100uA 0 00190 uA 100uA 0 00190 uA 2 mA 0 mA Perform input zero operation to calibrator range locked zero output 1mA 0 0000190 mA 1mA 0 0000190 mA 20 mA OmA Perform input zero operation to calibrator range locked zero output 10mA 0 000200 mA 10mA 0 000200 mA 200 mA 0 mA Perform input zero operation to calibrator range locked zero output 100mA 0 00530 mA 100mA 0 00530 mA 2A OA Perform input zero operation to calibrator range locked zero output 1A 0 0002260 A 1A 0 0002260 A 20A OA Perform input zero operation to calibrator range locked zero output 10A 0 004950 A 10A 0 004950 A 1 Based on 365 day Tcal 1 C 99 CL Absolute specifications See comments in Applicable Verification Tolerance section above regarding the impact of calibration uncertaintie
81. hassis Assembly 5 7 8508A Service Manual Bottom view TO CONNECTORS ON REAR AS SHOWN AND CONNECT OF DISPLAY BOARD n uj d a lt o z Q a a c z is Oo IL WHITE amp GREEN avw027f eps Figure 5 2 8508A Chassis Assembly cont 5 8 List of Replaceable Parts Parts Lists Figure 5 2 8508A Chassis Assembly cont NOT REQUIRED IF REAR INPUT FITTED avw028 eps 5 5 9 8508A Service Manual Table 5 3 A5 Bezel front panel Assembly nerorence Description muke Tot Qty Notes Designator Part No A1 Display PCB Assembly 1988711 1 C1 C2 Capicator ceramic 470 pF 10 2 kV 2397993 2 H1 Screws 8 32 x 3 8 295105 4 H2 Screw K25 x 8 POZIPAN SZP ST 2398217 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 1605272 1 MP4 Front Panel Decal 1607677 1 W1 Cable Assembly Front Input 2398051 1 5 10 5 Parts Lists List of Replaceable Parts RED WIRE BLACK WIRES FIT THIN N WIRE UNDER THICK WIRE PINK WIRE BROWN WIRE BLUE WIRE WHITE WIRE LOOP ONCE THROUGH FERRIT
82. he 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 resolution Transfer On and 100Hz Filter is used for calibration of all ACV ranges Reselect ACV 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 Ensure that the calibrator output is set to STANDBY and configured for Internal Guard EXT GRD is deselected Connect the Calibrator to the Multimeter as shown above Range Zero LF and HF Gain Calibration Procedure not in Spot Frequency mode Using the following procedure to calibrate range zero then range LF and HF gains on all ACV ranges at the voltages and frequencies detailed in Table 3 4 Just one range can be calibrated 1f required but for a full calibration start with the 200 mV range and work up to the 1kV range Calibration and Verification 3 Routine Calibration Table 3 4 AC Voltage Calibration Points and Sequence 8508A Range Point Voltage Frequency 200 mV Zero 5 Range 10 mV 1 kHz Range Gain LF 100 mV 1 kHz Range Gain HF 100 mV 60 kHz 2V Zero 0 5 Range 10 mV 1 kHz Range Gain LF 1V 1 kHz Range Gain HF 1V 60 kHz 20V Zero 0 5 Range 100 mV 1 kHz Range Gain LF 10V 1 k
83. ibration Performance Verification eene enne enne nenne nnne Equipment Requirements ssessseseesee eene nnne Interconnections iecore tee rid RHET EE Fee FEE Meca E d IR REAT 3 1 8508A Service Manual 3 2 Applicable Verification Tolerance and Conditions sss Preparation Ib eR VUIEPSITCcPMCP AG Voltage Checks iiri este ca e reta re Oe REDE eaa go Resistance Checks DC Current Checks AC Current Checks Frequency Checks Calibration and Verification 3 Introduction Introduction This chapter describes the calibration menus and lists the calibration and performance verification procedures for the Multimeter Remote commands for calibration of the Multimeter are described in Chapter 4 of the Users Manual Remote Operations using the IEEE 488 Interface In this chapter menu and button selections are shown as all caps text Calibration Overview An electronic autocal feature allows full calibration of all functions of the Multimeter from the front panel or remotely via the IEEE 488 2 Interface No hardware adjustments are necessary For each combination of function and range an appropriate calibration standard source is input At each setting one keystroke immediately calibrates to the standard by updating an internal non volatile calibration memory The Multimeter automatically determines whether the operation is to be a Zero or Range
84. ibration operations it is recommended that the user updates the stored CAL due date with the date for next recalibration For consistency this date should be the same as the calibration due date shown on any calibration stickers the user may also attach to the Multimeter 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 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 be used but it is recommended that one of the common date formats such as dd mm yy or mm dd yy is used for ease of interpretation 4 Press Enter to store the CAL due date Disable cal mode 1 Set the rear panel Calibration Enable switch to DISABLE 2 Apply a security seal to cover the rear panel Calibration Enable switch to prevent unauthorized access ACV Spot Frequency Calibration 3 30 The ACV Spot frequency mode calibration is not normally performed as part of routine calibration ACV Spot frequency calibration is only performed if the user intends to make use of spot frequency mode In spot frequency mode the accuracy of AC Voltage measurements can be improved by calibrating the Multimeter at specific frequencies of interest reducing frequency response flatness er
85. ies provided by the calibration equipment with the 8508A Relative to Standards specifications RSS summation is recommended Preparing for Calibration The following procedures represent the recommended order of calibration giving all the necessary setup commands 1 Allow the Multimeter to warm up under power in the specified environment for at least 4 hours 2 Press the CLEAR key select Pwr Up Dflt to restore the power up default configuration and display the DCV menu 3 Setthe rear panel Calibration switch to Enable Removal of any calibration sticker or Calibration and Verification Routine Calibration integrity seal covering the calibration switch will be necessary 4 Press the CAL key 5 The CALIBRATION menu is displayed The calibration menu appears and the CAL legend appears on the main display When entering CAL mode and selecting a function the optimum resolution for performing calibration in that function is automatically selected Refer to Table 3 2 for the full multimeter calibration sequence It is recommended that the default resolutions are used for calibration purposes Other resolutions may be selected and calibration operations performed but accuracy of Note calibration will be degraded if calibration is performed in lower resolutions A Caution When in CAL mode with the CAL legend appearing on the main display the function of the SAMPLE key is modified from normal operation If pressed the SA
86. ifications Introduction The Fluke 8508A has been designed specifically for metrologists Not only does it provide the performance metrologists need but it is specified in a way to allow users to really understand the uncertainties of the measurements and easily make allowance for those uncertainty contributions when performing measurement uncertainty analyses and compiling uncertainty budgets Contemporary metrology practices including ISO17025 based laboratory accreditation schemes require uncertainty analysis to be performed in accordance with the statistically based techniques described in the ISO Guide to the Expression of Uncertainty in Measurement often referred to as the GUM For convenience the 8508A specifications are quoted at a coverage factor of k 2 equivalent to a confidence level of approximately 95 as required by these methods Specifications are also provided at a confidence level of 99 Performance specifications for the 8508A consist of two elements the first is a contribution expressed as parts per million of the Reading and the second contribution is expressed as parts per million of the Range These must be evaluated and combined for the relevant reading and range values applicable to the measurement being made ensuring that both elements are evaluated on the same basis such as parts per million of the measured value or in absolute terms volts amps ohms etc The two elements are combined by adding algebraic
87. igure 4 6 Removing the A5 Bezel Assembly 4 9 8508A Service Manual Removing the A5A1 Display PCA Use the following procedure to remove the A5A1 Display PCA See Figure 4 7 1 Remove the A5 Bezel Assembly described earlier in this chapter 2 Remove the seven small self threading Philips screws holding the A5A1 Display PCA to the plastic bezel front panel 1 3 Lift the top of the A5A1 Display PCA until it clears the lip of the bezel and then pull the ASA1 Display PCA toward the lip of the plastic bezel 2 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 3 avw015f eps Figure 4 7 Removing the A5A1 Display PCA Maintenance 4 Access Procedures Removing the A6 Rear Input Assembly Use the following procedure to remove the A6 Rear Input Assembly See Figure 4 8 l 2 Position the unit on the work surface so it is bottom side up Remove both rear feet 1 a Remove the three hex screws from each foot b Ifthe feet are still in place pull them from the unit Remove the top and bottom covers 2X3 a Remove the one philips screw at the rear of each of the covers b Slide the covers toward the back of the unit and lift them off Remove the Rear Panel 4 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
88. ination for any given code 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 Center Self Test Errors When a Self Test is run and successfully completed no error messages result and the Multimeter is considered operational If a self test error does occur an error message beginning with zelf test failed shows on the display A function indicator and a test id number follow to complete the message See Table 4 3 for descriptions of the self test errors that might occur Table 4 3 Self Test Errors DC VOLTS Test No 10 Err 2101 P001 Main Ref Check Test No 11 Err 2101 P002 6 2V Ref Check Test No 20 Err 2201 P003 100mV Range Zero Check Test No 21 Err 2211 P004 1V Range Zero Check Test No 22 Err 2221 P005 10V Range Zero Check Test No 23 Err 2231 P006 100V Range Zero Check Test No 24 Err 2241 P007 100mV Range Positive Gain Check Test No 25 Err 2251 P008 100mV Range Negative Gain Check Test No 26 Err 2261 P009 1V Range Positive Gain Check Test No 27 Err 2271 P010 1V Range Negative Gain Check 4 13 8508A Service Manual
89. inputs The Multimeter may be left connected to the calibrator as shown above provided the calibrator output is set to STANDBY On the Multimeter Press CAL to enter the CALIBRATION menu and select SPCL Select Adc to initiate the calibration operation which will take approximately 3 minutes to complete Calibration is complete when the Busy legend goes out DC Voltage Calibration AA Warning The Calibrator can deliver a lethal electric shock To avoid electric shock when performing the following calibration procedures e Never touch any lead or terminal unless you are absolutely certain that no dangerous voltage is present e Make sure that signal leads are in a safe condition before you handle them in any way Initial Setup 1 Press the DCV key select the 200 mV range 2 Press the CONFIG key Select Filt 3 In calibration mode the resolution defaults to RESL7 in the DCV function It is recommended that this resolution is used for calibration of all DCV ranges 4 Reselect DCV 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 calibrator output is set to STANDBY and configured for Internal Guard EXT GRD is deselected 7 Connect the Calibrator to the Multimeter as shown above Calibration and Verification 3 Routine Calibration Range Zero and Gain Calibration Procedure
90. inty specifications 20Y 20Y 012 01x 2 01240 1x20 t 0 61 ppm of the ratio Additional Errors The 85084 specifications are listed for the maximum resolution in each function using the Normal reading mode For measurements taken in other resolutions or the Fast read mode additional error contributions listed in the Read Rate and Additional Uncertainty table must be included These additional contributions must be added algebraically to the relevant specifications For example measuring 10 V on the 20 VDC range at 5 digit resolution in Fast mode and applying the 365 day 1 C Absolute specifications G04 0 0 2 25 x 3 0 50 4 53 4 ppm of 10 V Other additional contributions apply in certain situations and are also to be added algebraically to the relevant specifications These additional contributions include the DC Accuracy specification to be applied when making DC measurements on the AC Voltage function when DC coupled and the High Voltage adder when making measurements above 300 V on the AC Voltage function 1 21 8508A Service Manual 1 22 Chapter 2 Theory of Operation Title Page Dicen nior een ernennen PES Overall Functional Description sessi 2 3 Main Assemblies iine anne ren 2 3 ldsdspndiie TU 2 6 2 1 8508A Service Manual 2 2 Introduction Theory of Operation 2 Introduction This chapter provides a board level theory of operation for the 8508A Reference Multimet
91. isplay PCA A6 Rear Input Assembly Rear input connections includes the A6A1 Rear Input PCA optional Normal operator interaction with the Multimeter begins at the front panel A5 which includes a keyboard for entering measurement configurations functions ranges etc and a display for verifying the selected configurations and for displaying measurement results Both the keyboard switches and the display are included on the A5A1 Display PCA A rubber keypad whose keys include a conductive backing provides switching information to ASAl A controller on the A4 Digital PCA provides the addressing strobing and storage of data coming from and going to the A5A1 Display PCA The data stored on the A4 Digital PCA includes both the manually entered configuration data for use by the display and other assemblies as well as the resulting measurement data for use by the display as measurement results Before being used by the Multimeter the stored configuration data is converted on the A4 Digital PCA from a parallel to serial format Similarily the A4 Digital PCA receives serial measurement data from the instrument and converts it to a parallel format for use as display data A rear panel IEEE 488 GPIB bus is intergrated into the format conversion process 2 3 8508A Service Manual A3 Ohms PCA to R Converter Input Select A2 AC PCA Range Selection Rectifier RMS MN gt Output Converter Buffer
92. l Lol Zero 0 Q Tru TruQ Lol Range Gain 1 kQ 20 kQ Normal Normal Lol Zero 0 Q TruQ TruQ Lol Range Gain 10 kQ 200 kQ Normal Normal Lol Zero 0 Q Range Gain 100 kQ 2MO Normal Normal Lol Zero 0 Q Range Gain 1 MQ 20 MQ Normal Normal Lol Zero 0 Q is Range Gain 10 MQ 200 MQ Normal Normal Lol Zero 0 Q x Range Gain 100 MQ 2 GQ Normal Normal Lol Zero 00 ae Range Gain 1GQ 20 GQ HiVO Zero 00 Range Gain Optional 1 20 GQ range gain is calibrated automatically during 2 GQ HiVQ range gain cal but may be calibrated separately after 2 GQ HiVQ range cal at 10 GQ if a standard is available The 100 MQ and 2 GQ NormalQ ranges must be calibrated before 2 GQ HiVQ range gain point Calibration and Verification 3 Routine Calibration Initial Setup and Connections 1 Press the Q key and select the 200 Q range 2 Press the CONFIG key and select Filt and 4wQ 3 Incalibration mode the resolution defaults to RESL7 in the resistance function It is recommended that this resolution is used for calibration of all resistance ranges Reselect Q 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 calibrator output is set to STANDBY and configured for Internal Guard EXT GRD is deselected On the calibrator select EX SNS 4 wire Connect the Calibrator to the Multimeter as shown ear
93. libration uncertainties for the calibration standards and for the process applicable to that calibration by combining those calibration uncertainties with the Multimeter Relative to Standards specifications as described in Chapter 1 Many Multimeter owners prefer using Fluke calibration services instead of maintaining their own standards to support their Multimeter To help ensure optimum performance from the Multimeter Fluke offers our calibration service at a variety of worldwide locations Our worldwide service network provides fast efficient calibration to ensure low uncertainties and optimum accuracy consistent with the original calibration at manufacture Calibration Points There is generally more than one calibration point for each range An initial measurement made when the calibration is triggered determines the intended calibration point The points for each range and function are listed later in this chapter 3 3 8508A Service Manual Non Nominal Values The Set facility allows the user to set the calibration target to the value of the calibration source available This facility is most useful when the user s calibration source is not available at the nominal values specified or when the user has knowledge of the actual output of the calibration source at the required points In these cases the use of the Set facility with a table of errors for the calibration source is recommended and will improve the accuracy of the Multime
94. lier in this chapter 8 Ifusing standard resistors in place of the calibrator refer to Measuring Resistance in Chapter 3 of the Users Manual for information regarding 4 wire resistance connections NormalQ Mode Calibration 1 Press the Q key and select the 2 Q range 2 Press the CONFIG key and select Filt and 4wQ Ensure Lol is deselected 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 NormalQ mode For the 2 GQ range use the 1 GQ standard resistor in place of the calibrator Just one range can be calibrated if required but for a full calibration start with the 2 Q range and work up to the 2 GQ range Note that EX SNS 4 wire is not available on the 5720A 100 MQ range and the 8508 7000K 1 GQ standard resistor is used as a 2 wire device with the calibrator 2 wire resistance zero used for the corresponding zero points 4WQ is deselected on the Multimeter when calibrating the 200 MQ and 2 GQ range range zero and range gain points On each range the Multimeter automatically recognizes the appropriate value as range Zero or range gain from the applied resistance value Note It is unlikely that the resistance standard will be at exactly the nominal value required The Set feature allows a user to enter the true output value of the calibration standard where it differs from
95. mbining 8508A Relative to Standards specifications and calibration uncertainties Note The Multimeter should be thoroughly checked to ensure it is operating correctly before attempting calibration A performance verification procedure appears later in this section Equipment Required for Calibration The equipment required for Calibration and Performance Verification is listed in Table 3 1 Table 3 1 Required Equipment for Calibration Adjustments and Performance Verification Minimum Use Equipment Name Specifications Recommended Models ranges and accuracy Multifunction Calibrator Po Fluke 5720A Signal Lead Set Po Fluke 5440 7003 7004 7005 Calibration Kit One 1 GQ Standard two Fluke 8508A 7000K precision low thermal emf 4 wire shorting devices and connecting leads PC Network Printer Cables PC Network Printer Cables Any Metrology bd software Po Fluke MetBase Metrology Calibration Software Po 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 by characterizing the outputs of the 5720A and 5725A at the points used for 8508A calibration Alternate equipment may be used but users should ensure it provides adequate calibration uncertainties Performance of the Multimeter after calibration should be determined by combining the applicable calibration uncertaint
96. meter range to be verified Set the calibrator output to STANDBY 3 35 8508A Service Manual Table 3 9 AC Voltage Verification Points and Sequence 8508A Range Voltage Frequency 8508A Filter Tolerance 200 mV 100 mV 20 Hz 10 Hz 0 0195 mV 100 mV 55 Hz 40 Hz 0 0175 mV 100 mV 1 kHz 100 Hz 0 0149 mV 100 mV 3 kHz 100 Hz 0 0175 mV 100 mV 10 kHz 100 Hz 0 0175 mV 100 mV 30 kHz 100 Hz 0 0445 mV 100 mV 60 kHz 100 Hz 0 0995 mV 100 mV 100 kHz 100 Hz 0 0995 mV 2V 1V 20Hz 10 Hz 0 000144 V 1V 55Hz 40 Hz 0 000119 V 1V 1 kHz 100 Hz 0 000099 V 1V 3 kHz 100 Hz 0 000119 V 1V 10 kHz 100 Hz 0 000119 V 1V 30 kHz 100 Hz 0 000295 V 1V 60 kHz 100 Hz 0 000795 V 1V 100 kHz 100 Hz 0 000795 V 1V 500 kHz 100 Hz 0 034000 V 1V 1 MHz 100 Hz 0 034000 V 20V 1V 1 kHz 100 Hz 0 00032 V 10V 20 Hz 10 Hz 0 00144 V 10V 55Hz 40 Hz 0 00099 V 10V 1 kHz 100 Hz 0 00119 V 10V 3 kHz 100 Hz 0 00119 V 10V 10kHz 100 Hz 0 00119 V 10V 30 kHz 100 Hz 0 00295 V 10V 60 kHz 100 Hz 0 00795 V 10V 100 kHz 100 Hz 0 00795 V 10V 500 kHz 100 Hz 0 34000 V 10V 1 MHz 100 Hz 0 34000 V 19V 1 kHz 100 Hz 0 00167 V 3 36 Calibration and Verification Performance Verification Table 3 9 AC Voltage Verification Points and Sequence cont 3 8508A
97. ms Rear Input a enw a eer idee 2 A rms Rear Panel Fuse Settling Time 200 uA to 200 mA Ranges to 10 ppm step size 2A Range to 100 ppm step size to 75 ppm step size to 30 ppm step size 20 A Range at to 300 ppm step size to 250 ppm step size to 100 ppm step size 10 A Filter Out lt 50 ms Filter In lt 1 s 1s 30s 5 minutes 1s 30s 5 minutes Introduction and Specifications Specifications 1 AC Voltage AC Voltage 5 Uncertainty Relative to Cal Stds Absolute Uncertainties Range Full Scale Frequency Hz ppm Reading ppm Range 24 hour 90 day 365 day 365 day 365 day TCal 1 C TCal 1 C TCal 1 C TCal 1 C TCal 5 C 95 Confidence Level 200 mV 199 990 0 1 10 80 70 120 70 120 70 160 70 165 70 10 40 80 20 120 20 120 20 130 20 140 20 40 100 60 20 100 20 100 20 110 20 115 20 100 2k 40 10 100 10 100 10 105 10 110 10 2k 10k 60 20 100 20 100 20 105 20 135 20 10k 30k 250 30 300 40 300 40 305 40 340 40 30k 100 k 400 100 700 100 700 100 705 100 765 100 2V 20V amp 1 999 900 1 10 70 60 100 60 100 60 140 60 150 60 200 V 19 999 00 10 40 70 10 100 10 100 10 105 10 115 10 199 990 0 40 100 50 10 80 10 80 10 85 10 90 10 100 2k 30 10 60 10 60 10 65 10 75 410 2k 10k 50 10 80 10 80 10 85 10 110 10 10k 30k 100 20 200 20 200 20 205 20 220 20 30 k 100 k 2
98. nd Follower 10V Output Check Test No 69 Err 2691 P053 1uA Current Sink Check Test No 70 Err 2701 P054 100nA Current Sink Check Test No 71 Err 2711 P055 10nA Current Sink Check Test No 72 Err 2721 P056 HV Ohms Follower Offset Check Test No 73 Err 2731 P057 HV Ohms Follower Output Current Check Test No 74 Err 2741 P058 HV Ohms Output Voltage and 240V Clamp Check Maintenance Self Test AC VOLTS Test No 80 Err 2801 P015 100mV AC Range Zero Input Check Test No 81 Err 2811 P016 100mV AC Range 179mV DC Input Checks at PreAmp Output Test No 82 Err 2821 P017 100mV AC Range 179mV DC Input Checks at PreAmp Output Test No 83 Err 2831 P018 1V AC Range Zero Input Check 2832 raw Test No 84 Err 2841 P019 1V AC Range 993mV DC Input Checks at PreAmp Output Test No 85 Err 2851 P020 1V AC Range 993mV DC Input Checks at PreAmp Output Test No 86 Err 2861 P021 1V AC Range 993mV DC Input Checks at RMS Converter Output Test No 87 Err 2871 P022 1V AC Range 993mV DC Input Checks at RMS Converter Output Test No 88 Err 2881 P023 10V AC Range Zero Input Check 2882 raw 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 P026 100V AC Range Zero Input Check 2912 raw Test No 92 Err 2921 P027 100V AC Range 9 78V DC Input Checks at PreAmp Output T
99. nd out guard control and data transfer circuits Control data from the A4 Digital PCA passes through the opto isolators and serves as input to a series of tri state latches These latches retain the control data and they provide the input to a series of relay drivers which in turn drive a series of configuration relays These relays establish the necessary connections between the various assemblies to perform the measurement called for from the front panel keyboard or GPIB inputs These relays also route analog data and associated guarding from the input terminals front and rear to the appropriate assemblies as defined by the measurement control data The A1 DC PCA in addition to switching the measurement configurations and the routing of input and measurement signals includes the circuits to perform the following functions e DC measurements Handles both DC voltage and dc current measurements e Analog to digital conversion ADC The ADC processes all measurement data volts ohms and current before routing it in digital form to the A4 digital PCA for display and GPIB access e Current to voltage conversion Both the ac and dc current measurement functions IDC and IAC use the same current shunts e Self Test Produces a variety of reference signals from 10 to 10 volts and places them on the internal signal bus for measurement and display These tests provide a high degree of certainty that the Multimeter is functioning corre
100. ndards without describing the process required to do so Characterization of the 5720A 5725A combination allows the 8508A to be calibrated with uncertainties lower than otherwise available from that equipment The characterization process determines the 5720A 57254 errors from nominal at the values required for 8508A calibration and may be performed using Fluke s recommended verification procedures appearing in the 5700A 5720A Service Manual as a guide If a characterized 5720A 5725A combination is available where the error from nominal at the various points required is known those errors may be taken into account during calibration to reduce the uncertainties The errors may be determined by measurement against suitable standards or may be taken from an applicable certificate of calibration The uncertainty of the characterized calibrator should be combined with the Multimeter Relative to Standards specifications to determine Multimeter performance after calibration RSS summation is recommended If the calibrator is not characterized to determine its errors from nominal its output should be assumed to be nominal at all points Its performance specifications should be 3 9 8508A Service Manual used to provide calibration uncertainties to be combined with the 8508A Relative to Standards specifications to determine the achieved Multimeter performance after calibration RSS summation is recommended See Chapter 5 for more details of co
101. ng in the High Voltage Resistance mode Voltages up to 240V may appear on the terminals To avoid electric shock when performing the following calibration procedures e Never touch any lead or terminal unless you are absolutely certain that no dangerous voltage is present e Make sure that signal leads are in a safe condition before you handle them in any way Press the Q key Press the CONFIG key and select Filt RESL7 and 4wQ Ensure Lol is deselected Select the required Multimeter range x D On the Calibrator select zero Q and Operate Alternatively if using a standard resistor connect the standard resistor for a 4 wire resistance zero For the 200 MQ range and above de select Ex SNS on the calibrator and de select 4WQ on the Multimeter 5 Onthe Multimeter press the INPUT key and select Zero Rng to initiate the zeroing operation The Busy legend will appear and then extinguish when the zero operation has completed 6 Onthe Calibrator select Range Gain point Output value Alternatively if using a standard resistor re connect the standard resistor to measure its resistance 7 Note the Multimeter s reading Compare the result with the allowable tolerance taking into account the actual value of the calibrator resistance output for this value or the calibrated value of the resistance standard used 8 Repeat steps 3 7 for the remaining ranges of the selected resistance mode For the 2 GQ and 20 GQ ranges the 85
102. nvoice Buyer for importation costs of repair replacement parts when product purchased in one country is submitted for repair in another country Fluke s warranty obligation is limited at Fluke s option to refund of the purchase price free of charge repair or replacement of a defective product which is returned to a Fluke authorized service center within the warranty period To obtain warranty service contact your nearest Fluke authorized service center to obtain 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 accident or abnormal condition of operation or handling including overvoltage failures caused by use outside the product s specified rating or normal wear and tear of mechanical components Fluke will provide an estimate of repair costs and obtain authorization before commencing the work Following repair the product will be returned to the Buyer transportation prepaid and the Buyer will be billed for the repair and return transportation charges FOB Shipping Point THIS WARRANTY IS BUYER S SOLE AND EXCLUSIVE REMEDY AND IS IN LIEU OF ALL OTHER WARRANTIES EXPRESS OR IMPLIED INCLUDIN
103. omponent with up to 1000 V DC bias on any range DC coupled gives ac de RN gt 90 dB DC 60 Hz 10 1 at 12 96 range 5 1 at 50 range 2 5 1 at full range MUTA 10 1 at 25 range 5 1 at full range IET 1 kV rms m 1 MQ in parallel with 150 pF Add 50 ppm Reading 50 ppm Range 20 uV Net Front Input Accuracy Net Rear Input Accuracy Wie ai Apply 24 hour or 20 minute Transfer Uncertainty specifications penc cic M 0 5s NEA EENAA lt 1 25s u lt 5s poc c HUM 50s B m Ne 5 of range to limit set by maximum V Hz Normal Fast Hvala nata 6 5 digits 4 5 digits puni 10 Hz 1 MHz 200 Hz 1 MHz e nee 10 ppm of Reading 2 digits t 2 digits 50 ms Introduction and Specifications Specifications AC Current AC Current 999 Uncertainty Relative to Cal Stds Absolute Uncertainties Range Full Scale rn ppm Reading ppm Range 24 hour 90 day 365 day 365 day 365 day TCal 1 C TCal 1 C TCal 1 C TCal 1 C TCal 5 C 95 Confidence Level 200 uA 199 990 0 1 10 200 100 250 100 250 100 475 100 500 100 10 10k 200 100 250 100 250 100 475 100 500 100 10k 30k 500 100 600 100 600 100 650 100 710 100 30k 100k 0 35 100 0 4 100 0 4 100 0 4 100 0 4 96 100 2mA amp 1 999 900 1 10 200 100 250 100 250 100 290 100 310 100 20 mA 19 9990 00 10 10k 200 100 250 100 250 100 280 100 300 100 1
104. on Alternatively the IMHz frequency reference may be used directly as an input signal for the Multimeter for frequency calibration Initial Setup and Connections 1 Press the ACV key select the 2 V range 2 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 3 Ensure that the calibrator output is set to STANDBY and configured for Internal Guard EXT GRD is deselected 4 Connect the Calibrator to the Multimeter as shown above If required connect the calibrator rear panel phase lock input to a 1MHz reference frequency and enable phase locking via the front panel menus Procedure 1 On the calibrator select 1V 1MHz Operate 2 Onthe Multimeter Press CAL to enter the CALIBRATION menu and select SPCL 3 Select Freq to initiate the calibration 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 Lol 2 wire and 4 wire for the front and rear inputs Initial Setup and Connections 1 Press the CAL key and select Quit 2 From the CAL DUE menu select Quit 3 The Multimeter will exit from CAL mode the CAL legend on the main display will extinguish and he right hand dis
105. onnections The Fluke 8508A 7000K Calibration kit contains a specially designed lead set which connects directly to the terminals of the Multimeter the 5720A and the 57254 for the purpose of Multimeter calibration It is recommended that this lead kit be used to avoid introducing measurement errors due to interconnections and to duplicate the 3 8508A Service Manual configuration used by Fluke for Multimeter calibration Figure 3 1 shows the interconnections used in detail If alternate leads are substituted make sure they are metrology grade leads and of adequate voltage and current ratings Leads should be kept as short as possible constructed from low capacitance low leakage dielectric material PTFE with low thermal emf terminations and exactly duplicate the configuration and interconnections shown When calibrating the 2 GQ and 20 GQ resistance ranges the 1 GQ standard resistor supplied in the 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 devices for use when performing the non volatile input offset adjustments at the front and rear input terminals These devices link the input terminal
106. ontains an illustrated list of replaceable parts for the 8508A Reference Multimeter to the board level only Parts are listed by assembly alphabetized by reference designator Each assembly is accompanied by an illustration showing the location of each part and its reference designator The parts lists give the following information e Reference designator e An indication if the part is subject to damage by static discharge e Description e Fluke stock number e Total quantity e Any special notes i e factory selected part A Caution A symbol indicates a device that may be damaged by static discharge How to Obtain Parts Electrical components may be ordered directly from the manufacturer by using the manufacturers part number or from the Fluke Corporation and its authorized representatives by using the part 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 Reference designator Part number and revision level of the pca containing the part Instrument model and serial number How to Contact Fluke To contact Fluke call one of the following telephone numbers USA 1 888 99 FLUKE 1
107. or was true after a read transfer Tested during read sequence 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 a4 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 Li State Change Timeout Interface state change between read wait and write states did not occur within timeout period Interface hardware fault suggests ULA or associated signals problem Ts A D timeout A D did not produce RTx within hardware timeout period after Cl A D or hardware fault Suggests A D not being initiated or RTx not getting back to digital ULA Could be an analog problem if the A D locks up oF No RTx after abort Latched RTx did not appear after abort sent A D or Cl hardware fault Suggests A D not being initiated or RTx not getting back to digital ULA Could be an analog problem if the A D locks up Oe Switching counter Switching counter in operative when tested at inoperative power on suggests ULA or associated signals problem 8508A Service Manual S006 Serial Loor Mismatch xx id KHM Is the actual data received in binary format See Table 4 7 for descriptions of the serial loop mismatch errors Table 4 7 Serial Loop Mismatc
108. ost recently entered serial number is shown and the keyboard is activated A numeric value can be entered 3 7 8508A Service Manual Enter Quit adj138f eps SER Menu The SER menu provides the selection Enter Stores the new serial number de activates the keyboard and reverts to the SPCL menu uit Reverts to the SPCL menu leaving the old serial number intact Hvlin Menu This menu sequence is obtained by selecting Hvlin from the SPCL menu It allows the linearity of the 1kV DC range to be calibrated with the application of five input signals of 1000V 500V 0V 500V and 1000V in turn with the 1kV DC range selected On entry to the menu the user is prompted to apply the first input signal required and step through the sequence PRELU HEAT FREU MEAT FREU MEAT Hvlin 1000 PREM CALC ar e Measure B za adj135f eps Hvlin Menus Pressing the SAMPLE key initiates the calibration operation at the signal level displayed for the step in progress and also saves the result for calculation of the Hvlin linearity correction factor at the end of the sequence FREU Moves back to the previous menu allowing the user to repeat the previous step in the sequence ifrequired HERT 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
109. oti ETFOES c 6er tree e e E e Pi FERAE ERN Pr edu ee Nene 14 18 Device Dependant Errors uueeeseesseenseenseenneennensnennnennnnennnnnsennse nennen nnne 14 19 8508A Service Manual 4 2 Maintenance 4 Introduction Introduction This chapter contains access procedures for replaceable assemblies PCAs and error messages assocated with the self test procedure All of the access procedures describe how to remove a PCA or assembly In all cases unless otherwise noted the re assembly replacement procedure is a logical reversal of the removal procedure Access Procedures This section of the manual includes access procedures for the following assemblies Al DC PCA A2 AC PCA A3 Ohms PCA A4 Digital PCA A5 Bezel Assembly ASAI Display PCA A6 Rear Input Assembly Before You Start To ensure 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 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 Be aware that removing either or both of the cover s will void calibration of the Multimeter Before removing the covers place the Multimeter on an appropriate bench top or work surface To avoid damage to the Multimeter from static electricity use best practic
110. own 9 of range 18 96 on 1000 V range Remote Interface IEEE 488 2 Warranty ecrire tee 1 Year 1 7 8508A Service Manual Maximum Voltage and Current Inputs Notes to maximum voltage and current input specifications Maximum DC input equal to maximum rms input Maximum peak input is rms x 1 414 DC and AC Voltage Specifications apply equally to front and rear input terminals except where noted below Front to rear isolation allows opposing polarity of maximum terminal voltage on each input Digital O Ground DigGnd is internally connected to Safety Ground Ground Maximum rms terminal voltages Sense Hi Hi 250V Sense Lo 1000 V 1000 V Lo 250V 1000 V 1000 V A 1000 V 1000 V 1000 V 1000 V Guard 1000 V 250V 250V 1000 V 1000 V DigGnd 650 V 650V 650 V 650 V 1000 V 1000 V Ground OV 650 V 650 V 650 V 650 V 1000 V 1000 V Notes The A terminal is open circuit in these functions In 4wV mode Sense Hi is internally connected to Hi and Sense Lo is internally connected to Lo DC and AC Current Maximum rms terminal voltages Sense Hi Hi 250V Sense Lo 1000 V 1000 V Lo 250V 1000 V 1000 V A 5V 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 OV 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 20A 20A n a
111. p you to determine 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 register your product visit register fluke com Specifications Figure 1 1 shows the overall dimensions ofthe 8505A Reference Multimeter 427 mm 16 8 in 487 mm 19 2 in avw001f eps Figure 1 1 8508A Dimentional Outline Drawing Introduction and Specifications 1 Specifications General Specifications Power Voltage 115 V Setting ana near 100 V to 120 V rms 10 230 V Setting ssssseeeeeee 200 V to 240 V rms 10 6 Frequency 47 Hz to 63 Hz Consumption lt 80 VA Dimensions ni ee E 88 mm 3 5 inches Mone 427 mm 16 8 inches Depth m 487 mm 19 2 inches Weight kei 11 5 kg 25 5 Ibs Environment Temperature Operating 0 C to 50 C Specified Operation 5
112. play will revert to the currently selected function menu 4 Disconnect all calibration leads and connect a 8508 7000K precision 4 wire short device to the front input terminals and also if fitted to the input terminals as shown above Procedure Omit step 4 if the Multimeter is not fitted with rear input terminals 1 Press the DCV key 2 Press the INPUT key and select Front 3 From the INPUT menu select Zero Func to perform zero offset adjustment on all ranges 4 From the INPUT menu select Rear Repeat step 3 Press the Q key and select the 2 range 3 29 8508A Service Manual 6 Press the CONFIG key and select Filt Lol and 4wQ Repeat steps 3 and 4 7 Press the CONFIG key and select 2wQ Repeat steps 3 and 4 8 Press the CONFIG key select 4wQ and de select Lol Repeat steps 3 and 4 9 Press the CONFIG key and select 2wO Repeat steps 3 and 4 10 Press the OPLUS key and select TruQ From the TruQ menu the 2Q range 11 Press the CONFIG key and select Filt and Lol Repeat steps 3 and 4 12 Press the CONFIG key and de select Lol Repeat steps 3 and 4 13 Press the OPLUS key and select HiVQ From the HiVQ menu the 20MQ range 14 Press the CONFIG key and select Filt and 2wQ Repeat steps 3 and 4 15 Press the CONFIG key and select 4wQ Repeat steps 3 and 4 16 Press the DCV key and remove the shorting devices from the input terminals Cal Due Date Entry and Calibration Mode Disable On completion of all cal
113. put Fuse 1 Power Input Fuse Action Fuse Rating Fluke Manufacturer Fuse F1 IEC 127 UL CSA Part No amp Type No TH Schurter 2 A 250V 20204 TIS MAG Time delay HBC Leo TUA 90 9509 001 2505 TH Schurter A 1 A 250V 202 230 VAC Time delay HBC 630 mA 1 A 250 920203 001 2502 Maintenance Self Test Rear Input Current Fuse F2 Rear Inputs Option The rear input option includes a fuse F2 to limit the current at the rear input A terminal to 2A The fuse is located at the rear of the Multimeter just to the left of the current input terminal A A half twist of the fuse cap releases the fuse for inspection or replacement Use the fuse specified in Table 4 2 when replacement is necessary Table 4 2 Current Function Rear Input Fuse 2 FH N Fuse Rating Manufacturer Fuse Action IEC 127 UL CSA Fluke Part No amp Type No 2A 20071 Beswick 1 Fast acting HBC ES AUN 9200 eswick S50 Self Test This section of the manual contains a collection of the error codes which might be generated either on the display of the Multimeter or by way of the IEEE 488 system bus Error codes described in this section are shown in tabular form with both the error codes and the descriptions of the most likely faults causes or conditions Typically the error codes contain two parts a four digit address code and a two digit id code However some error codes consist only of the four digit address The comb
114. ral Specifications esses Maximum Voltage and Current Inputs essen DC and AC Volt ge m DC and AC Currents s ea heile ER EL Resistance and Temperature sss DC Volt gen EET DE Current nee een teentsrr ee AON dlc ER Pel Resistance nut PH y uscite Read Rate and Additional Uncertainty sse Applying the Specifications sess Ioni Absolute and Relative Specifications sese Applying User s Calibration Uncertainties essere Operating and Calibration Temperature Ranges nenenenen Applying Temperature Coefficient Specifications Ratio Measurements u PRO Ur TREE ORI HRS ER Ue He RM RERUM enger Additional Errors cccccccsscsscesseeseceeeeeeseceaecaceseeeaecaeeeneeeeceaeeaeeeeceaeeaeeeeeeaeeaee 2 Theory of Operation ee Introduction Overall Functional Description essessesseesseensesnnennnennnennnnnnnnennnnne nn Main Assemblies tiere een Ee IHR CETERI ae P degr s Power Supplies EE 8508A Service Manual 3 Calibration and Verification eeeeeeee eene nnnm Introduction issues TIPS Calibration Overview te nassen us e eee adno Calibration Interval and Performance c ccccecsecss
115. re current reversal resistance measurement with readout of equivalent temperature 2 wire and 3 wire selectable without current reversal Refer to Resistance specifications for additional details UU TE ER 200 C to 660 C readout also available in F or K S ITS 90 or Callendar van Dusen Entry and storage of coefficients and nominal resistance for up to 100 probes 1 8508A Service Manual Read Rate and Additional Uncertainty Read Rate and Additional Uncertainty Read Rate Additional Errors Function Resolution Filter readings second ppm Reading ppm Range Frequency Hz Normal Fast Normal Fast DCV DCI amp Ohms 8 1 25 1 6 0 0 0 4 0 1 er 7 1 6 1 2 0 0 1 0 05 6 2 35 1 0 0 5 042 5 5 35 150 045 0425 ACV amp ACI 6 1 1 50 040 10 1 5 040 40 1 2 040 100 1 0 0 5 1 1 50 0 5 10 1 5 0 5 40 1 2 0 5 100 2 0 5 ACV Transfer Off 1 1 25 200 20 10 1 2 5 200 20 40 1 200 20 100 4 200 20 PRT amp Tru Ohms 8 1 90 1 30 0 0 id 7 1 30 1 10 0 0 1 6 1 4 1 3 1 0 0 5 5 1 3 1 3 045 Notes to Performance Specifications Fluke guarantees 8508A performance verification using specifications stated to 99 confidence level 1 2 Specifications apply for max resolution in each function normal mode Assumes 4 hour warm up period 3 Input zero or offset null required whenever the temperature moves more than 1 C from the temperature at which the previous 4
116. red omit steps 2 4 for the Range Gain Point 3 20 Calibration and Verification 3 Routine Calibration Zero Point 1 Onthe Multimeter select the required range 2 On the Calibrator select zero Q and Operate Alternatively if using a standard resistor connect the standard resistor for a 4 wire resistance zero For the 200 MQ and 2 GQ ranges de select Ex SNS on the calibrator and de select 4WQ on the Multimeter On the Multimeter press CAL to enter the CALIBRATION menu 4 Press SAMPLE to initiate the calibration operation Calibration is complete when the Busy legend goes out and the calibrated measurement is displayed Range Gain Point 1 On the Calibrator select the Range Gain point resistance value Alternatively if using a standard resistor re connect the standard resistor to measure its resistance For the 2 GQ range the 8508 7000K 1 GQ standard resistor is used in place of the calibrator For the 200 MQ and 2 GQ ranges de select Ex SNS on the calibrator and de select 4WQ on the Multimeter 2 Onthe Multimeter Press CAL to revert to CALIBRATION menu Select Set on the CALIBRATION menu 4 Use the numeric keys with the SET VALUE menu to key 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 On the Calibrator set STAND
117. ror During HF trim Cal 2004 Error During Input Zero The input signal was outside Zero 1 of full range 2005 Error During Lol Zero Cal The input signal was outside Zero 1 of full range zgje Error During Lol Gain Cal The input signal was outside full range 10 of full range 2 008 Error During A to D Cal error numbers between 2030 and 2089 see section 2 z010 Error During Frequency Cal z lz Error During DCcp Cal z025 Error During HiV Lin Read z026 Error During HiV Lin Calc z027 Error During 2wr Ohms Calc Corruptions z i4 Serial Number Corrupt 2015 Cal Due Date Corrupt z lr Bus Address Corrupt z ia Line Frequency Corrupt z z0 Invalid Corrections ram Combined corrections checksum error z zi Calibration Corrupt z022 NV RAM Write Failure Micellaneous z103 Bad Data from Analog Sys z 2 NV Ram write failure z z1 Engine Load factor err z z4 Engine Store factor err 4 20 Chapter 5 List of Replaceable Parts Title Page IURI 15 3 How to Obtain Parts tete rete pete o ee eo ote eo Eee et ebat ee REPRE epe ERNER 5 3 How to Contact Fluke cccccccccscssssoccccccccocsessssrecccescossessssececescossessenscesessoens 15 3 Pas SS NETT E 5 4 5 1 8508A Service Manual 5 2 List of Replaceable Parts 5 Introduction Introduction This chapter c
118. rors at these points The following procedure provides guidance on spot frequency calibration for users wishing to make use of Spot frequency mode Calibration and Verification 3 Performance Verification To Calibrate at Spot Frequencies Spot Calibration is available only when in AC Voltage function with Spot already selected on the ACV CONFIG menu Each spot six per range can be calibrated at a valid input frequency to a non nominal RMS value In subsequent use frequency response flatness errors are reduced within 10 96 of the calibrated spot frequency Assuming that the Multimeter is in calibration mode and the setup is connected as described above under nitial Setup and Connections for routine calibration The configuration defaults to Tfer and RESL6 both required Proceed as follows 1 Select ACV and select the required Range 2 Press the CONFIG key and select Spot 3 Press the CAL key The CALIBRATION menu is displayed 4 Select Set The SPOT CAL menu is displayed 5 Select the soft key for the required spot 1 to 6 Sp1 to Sp6 The SPOT x 1 to 6 RMS menu is displayed 6 Key in the true RMS output value of the standard then select Enter The SPOT FREQUENCY menu is displayed showing the frequency at which the spot will be calibrated 7 Press SAMPLE to initiate the calibration operation Calibration is complete when the Busy legend goes out and the calibrated measurement is displayed The menu display revert
119. s voltage sensing of the unknown resistor synchronously reverses with the current The true ohms ratio function uses a similar current reversal process However the current is applied to both unknown resistors simultaneously Power Supplies 2 6 The Multimeter has two types of power supplies out guard supplies and in guard supplies The out guard supplies provide power for the digital earth ground side of the Multimeter This includes the A4 Digital PCA the A5A1 Display 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 transformer It has a single 24 V center tapped secondary which provides ac power for both the out guard and in guard power supplies On the A4 Digital PCA the 24 V ac drives three conventional rectifiers and regulators to provide 5 V 8 V and 17 V sources for the out guard circuits The 5 and 8 volts provide power for out guard digital logic circuits the 17 volts along with a driver on the A4 Digital PCA supplies the power 17 V ac to drive the primary of the in guard transformer T1 Transformer T1 has 3 secondaries which drive a series of conventional rectifiers
120. s and use of other specifications AC Current Checks Equipment Configuration 1 Ensure that the calibrator output is set to STANDBY and configured for Internal Guard EXT GRD is deselected Connect the equipment as described for Routine Calibration Press the ACI key Press the CONFIG key Select RESL6 and 100Hz Filter 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 poge Cu sp 3 41 8508A Service Manual Procedure Repeat the following sequence for each range starting with the 2001LA range and working up to the 20A range as listed in Table 3 12 1 Select the required Multimeter range 2 Ontbhe calibrator set the output to the current and frequency for the point being verified as listed in Table 3 12 Set the output to OPERATE 3 Note the Multimeter s reading Compare the result with the allowable tolerance taking into account any known error from nominal of the calibrator for this output 4 Repeatsteps 2 4 for each point to be verified on the Multimeter s range to be verified 5 Repeat steps 1 5 for each Multimeter range to be verified Set the calibrator output to STANDBY Table 3 12 AC Current Verification Points and Sequence 8508A Range Current Frequency Tolerance 200 uA 100 uA 3
121. s in the following order Input Lo to Input Hi to Sense Hi to Sense Lo If these devices are not available it is recommended that a U shaped piece of thick bare copper wire be used to link the terminals in the same manner Calibration and Verification 3 Routine Calibration Link guard and ground terminal 5725A li Link guard OUTPUT and ground HI tO terminal io XQ CURRENT OUTPUT Equivalent Calibration Lead Connections Connections Using Calibration Lead E Included in Calibration Kit 8508A 7000K nec LUKE 8508A REFERENCE MULTIMETER 1 GQ Standard 4 wire Zero PCB Included in Calibration Kit 8508A 7000K Included in Calibration Kit 8508A 7000K adj381f eps Figure 3 1 Equipment Connections Required for Calibration 3 13 8508A Service Manual ADC Calibration ADC analog to digital converter calibration aligns the different resolutions available from the Multimeter s analog to digital converter so that there are no significant differences in readings when changing resolutions with a constant input value It is recommended that ADC CAL is only performed if performance verification indicates significant resolution differences If required it is recommended that ADC calibration is performed before any other calibrations No external equipment or signals are required to perform ADC calibration Procedure 1 Ensure that no signals are present on the Multimeter s
122. s to the SPOT CAL menu 8 Onthe Calibrator set STANDBY 9 Onthe 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 metrology personnel who have access to a standards laboratory with equipment available to verify the performance of an instrument of this level of accuracy The procedure assumes users are familiar with relevant best measurement practice and will take precautions to avoid introducing errors from sources such as thermal emfs leakages electromagnetic interference etc It also assumes users will make adequate allowance for equipment stabilization and measurement settling times This routine performance verification procedure describes the test points and sequence of operations required to check the Multimeter and assumes calibration references of adequate traceable uncertainty are available in this case a Fluke 5720A calibrator and 5725A amplifier used with an 8508A 7000 Calibration Kit The procedure assumes the user is able to calibrate and characterize the calibration standards without describing the process required to do so Refer to the Routine Calibration section for more information on the characterization process 3 31 8508A Service Manual Equipment Requirements
123. sistance standard will be at exactly the nominal value required The Set feature allows 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 Calibration and Verification 3 Routine Calibration Zero Point 1 2 On the Multimeter select the required range On the Calibrator select zero Q and Operate Alternatively if using a standard resistor connect the standard resistor for a 4 wire resistance zero On the Multimeter press CAL to enter the CALIBRATION menu Press SAMPLE to initiate the calibration operation Calibration is complete when the Busy legend goes out and the calibrated measurement is displayed Range Gain Point 1 On the Calibrator select Range Gain point Output value Alternatively if using a standard resistor re connect the standard resistor to measure its resistance On the Multimeter Press CAL to revert to CALIBRATION menu Select Set on the CALIBRATION menu Use the numeric keys with the SET VALUE menu to key in the true output value of the calibrator or the value of the resistance standard at the range gain value then press Enter Press SAMPLE to initiate the calibration operation Calibration is complete when the Busy legend goes out and the calibrated measurement is displayed On the Calibrator set STANDBY Press the Q key
124. so omit steps 3 5 On each range the Multimeter automatically recognizes the appropriate value as range Zero or range gain from the applied signal amplitude 1 Onthe Multimeter select the required Range 2 Onthe Calibrator select Output Current and Frequency Operate 3 Onthe 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 legend goes out and the calibrated measurement is displayed 7 Onthe Calibrator set Output to STANDBY On the Multimeter press ACI key to revert to the ranges menu Frequency Calibration The Multimeter frequency calibration operation requires a signal at exactly IMHz Set is not available on the Multimeter for frequency calibration If the calibrator frequency output is not exactly nominal or sufficiently close to nominal it may be phase locked to an external reference frequency at the required output frequency applied to its rear panel phase lock input for example from a laboratory frequency standard or off air reference receiver If used the calibrator should be disconnected from the frequency reference and phase locking disabled before attempting any other calibration operations with the calibrator Calibration and Verification 3 Routine Calibrati
125. ss it By limiting the current to a value of 1X10 the voltage drop is equal to the resistance value e g 1 mA through 2 12 KQ 2 12 V To accommodate range changes the reference current changes to match the selected range The reference current starts at 2nA for the 2 GQ range and increases to 1 mA for the 2 Q range A high gain inverting amplifier with low input current and low offset voltage performs the voltage 2 5 8508A Service Manual measurement across the unknown resistor Configuration relays on the Al DC PCA perform the change in terminal connections between two and four wire measurements The A3 Ohms PCA includes an alternative high resistance measurement feature for resistance measurements above 20 MQ These measurements use 10 times the standard stimulus current and result in a 10 times increase in the voltage across the resistor This high voltage resistance feature enables the Multimeter to make quiter and faster measurements It also enables the inclusion of a 20 GQ resistance range Another feature included on the A3 Ohms PCA is true ohms This feature eliminates the input offset voltage from the measurement circuit by continuously reversing the direction of current flow through the unknown resistence The stimulus current reversal is timed so that the current flows continuously thus maintaining identical and constant self heating of the unknown in both forward and reverse measurements To ensure same polarity measurement
126. ssed Quit Reverts to the CALIBRATION menu deleting the set value from store 3 5 8508A Service Manual SPOT CAL Menu This menu is obtained by pressing the Set key in the CALIBRATION menu when the Multimeter is in ACV Spot Frequency mode It provides a means of calibrating the Multimeter at any of six user specific spot frequencies at non nominal calibration values for each ACV range The Multimeter will already be set to an ACV range on entry to the menu adj140f eps SPOT CAL Menu This menu allows a user to select a spot frequency Spx for the selected range It defines six menu keys Srl Displays the SPOT 1 RMS menu where users define the RMS value for the Spot Frequency 1 calibration point on the currently selected range Lh PIE Same as Sp1 but permitting their own RMS values to be defined SPOT 1 to 6 RMS Menus On entry to one of the six SPOT x 1 to 6 RMS menus the nominal cardinal 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 SPOT n EMS Enter uit 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 Duit Reverts to the SPOT CAL menu not storing any new Spot value Note The SAMPLE key is still enabled in the next menu SPOT F
127. strument has been supplied in a safe condition This manual contains information and warnings that must be observed to keep the instrument in a safe condition and ensure safe operation Using or servicing this Multimeter in conditions other than as specified in the Service Manual could compromise your safety To use the Multimeter correctly and safely read and adhere to the precautions on the Safety Page and follow all the safety instructions or warnings given throughout this manual and the Users Manual that relate to specific measurement functions In addition follow all generally accepted safety practices and procedures required when working with and around electricity 8508A Service Manual A A Safety Read First Warning To avoid possible electric shock personal injury or death read the following before using the Multimeter Usethe Multimeter only as specified in this manual or the protection provided by the Multimeter might be impaired Do not use the Multimeter in wet environments The Multimer can output lethal voltages Use it only as described in this manual Inspect the Multimeter before using it Do not use the Multimeter if it appears damaged Pay particular attention to the insulation around the connectors Inspect the test leads before use Do not use them if insulation is damaged or metal is exposed Check the test leads for continuity Replace damaged test leads before using the Multimeter Verify the
128. t They appear here for completeness SPCL Menu The SPCL menu appears after pressing the Spcl key in the CALIBRATION menu At the same time the Multimeter is placed in special calibration mode and the Special CAL legend appears on the 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 dc Frea Hulin ClrHU Seri Huit adj137f eps SPCL Menu The SPCL menu provides the selection Ser Permits entry ofthe Multimeter s serial number Ace Aligns the different resolutions available from the Multimeter s main analog to digital converter so that there are no significant differences in readings when changing resolutions with a constant input value No external input signals are required for this calibration Calibration is initiated directly by making this selection from the SPCL menu Frea Calibrates the frequency counter against an external source Calibration is initiated directly by making this selection from the SPCL menu Hulin Selects the sequence required to correct the linearity of the IkV DC range ClrHu Provides the capability to clear a section of the non volatile memory for test purposes only puit Reverts to the CALIBRATION menu SER Menu This menu is obtained by pressing Ser in the SPCL menu On entry to the menu the m
129. t 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 1 V and frequency to IMHz Set the output to OPERATE 4 Note the Multimeter s frequency reading Check the result is within 0 000012MHz taking into account any known error from nominal of the calibrator output frequency for this point 5 Setthe calibrator output to STANDBY 3 43 8508A Service Manual 3 44 e static awareness A Message From Fluke Corporation Some semiconductors and custom IC s can be damaged by electrostatic discharge during handling This notice explains how you can o minimize the chances of destroying such devices i iole 2 1 Knowing that there is a problem 2 Leaning the guidelines for 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 i 3 DISCHARGE PERSONAL STATIC BEFORE HANDLING DEVICES USE A HIGH RESIS 1 MINIMIZE HANDLING TANCE GROUNDING WRIST STRAP 2 KEEP PARTS IN ORIGINAL CONTAINERS UNTIL READY FOR USE 4 HANDLE S S DEVICES BY THE BODY 5 USE STATIC SHIELDING CONTAINERS FOR 8 WHEN REMOVING PLUG IN ASSEMBLIES HANDLING AND TRANSPORT HANDLE ONLY BY NON CONDUCTIVE EDGES AND NEVER TOUCH
130. t flukes iis eret reete ett ret a Cen este nein Specifications teens een nenne ote ei A harten rese PEE ed ee ud eda cepas General Specifications esses ener enne Maximum Voltage and Current Inputs sss DC and AC Voltage ssssssssssseeeeee eee nennen enne nennen nnn nnne DC and AC Current iiit ERROR PR a NER HR PAR SR REPRE emo Resistance and Temperature sss nennen IA DIL M Lm lbezSl le EXORITUR AC CUITeDU oio tton ee MID UOI MEI EE Resistance aie pte pingit ped PRO PM IR pr ES Tempera e cecene a Read Rate and Additional Uncertainty essere Applying the Specifications sss eene Introduction uns nein einsehen irre Absolute and Relative Specifications Applying User s Calibration Uncertainties essen Operating and Calibration Temperature Ranges eennnennenn Applying Temperature Coefficient Specifications Ratio Measurements ssssssseseseseeeeeeen enne ener ethernet nnne ens Additional Erf rs iret teer Diener ee 8508A Service Manual 1 2 Introduction and Specifications 1 Introduction Introduction The Fluke 8508A Reference Multimeter hereafter the Multimeter is designed for the most demanding measurement applications and provides extremely high measurement precision in both stand alone and systems applications This Service Manual provides the information
131. ter s calibration Enabling Access to Calibration Mode The setting of a Calibration switch on the rear panel enables or restricts access to the calibration mode Setting the switch to ENABLE allows access to the calibration mode via the front panel CAL key and the CALIBRATION menu and also enables the remote IEEE 488 interface calibration commands Setting the switch to DISABLE and applying an integrity seal or calibration sticker to cover the Calibration switch is a convenient way to ensure the security of calibration and to prevent unauthorized access to the switch Calibration Menus Accessing the Calibration Menus and Calibration Mode Pressing the CAL key on the front panel causes the Multimeter to respond as follows 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 become inoperative CLR TEST OFFSET PRT and INPUT Also the function of the SAMPLE key changes to become the trigger key for initiating a calibration operation A Caution When in CAL mode with the CAL legend appearing on the main display the function of the SAMPLE key is modified from normal operation If pressed the SAMPLE key will initiate a calibration operation and permanently alter the Multimeter s
132. ternal Guard EXT GRD is deselected Connect the equipment as described for Routine Calibration Press the O key Press the CONFIG key Select Filt RESL7 and 4WQ 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 3 37 8508A Service Manual Procedure Perform the following sequence for each resistance mode and each range as listed in Table 3 10 starting with the 2 Q range and working up to the 2 GQ range for the NormalQ and NormalQ Lol resistance modes Then continue the sequence for the TruQ and TruQ Lol modes starting with the 2 Q range and working up to the 20 kQ range Finally complete the sequence for the HiVQ mode starting with the 20 MQ range and working up to the 20 GQ range An input zero operation is performed on each Multimeter range prior to performing the range verification measurements with the calibrator set to Zero Q A separate zero operation is required on each range for each resistance mode Note that EX SNS 4 wire is not available on the 5720A 100 MQ range and the 8508 7000K 1 GQ standard resistor is used as a 2 wire device with the calibrator 2 wire resistance zero used for the corresponding zero point AWO is deselected on the Multimeter when checking the 200 MQ and 2 GQ range range zero and range gain points AA Warning The Multimeter can deliver a lethal electric shock when operati
133. the value required for verification in the negative polarity 7 Note the Multimeter s reading Compare the result with the allowable tolerance taking into account any known error from nominal of the calibrator for this output 8 Setthe calibrator output to STANDBY Table 3 8 DC Voltage Verification Points and Sequence 8508A Range Voltage Tolerance 200 mV 0 mV Perform input zero operation to calibrator range locked zero output 100 mV t 0 00072 mV 100 mV 0 00072 mV 2V OV Perform input zero operation to calibrator range locked zero output 1V 0 0000045 V 1V 0 0000045 V 20 V OV Perform input zero operation to calibrator range locked zero output 1V 0 000009 V 10 V 0 000045 V 19 V 0 000081 V 1V 0 000009 V 10 V 0 000045 V 19 V 0 000081 V 200 V OV Perform input zero operation to calibrator range locked zero output 100 V 0 00065 V 100 V 0 00065 V 1000 V OV Perform input zero operation to calibrator range locked zero output 1000 V 0 0066 V 1000 V 0 0066 V 1 Based on 365 day Tcal 1 C 99 CL Absolute specifications See comments in Applicable Verification Tolerance section above regarding the impact of calibration uncertainties and use of other specifications Calibration and Verification 3 Performance Verification AC Voltage Checks AA Warning The Calibrator can deliver a lethal electric shock To avoid electric shock when
134. them in any way Equipment Configuration 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 hand display Procedure Repeat the following sequence for each range starting with the 200mV range and working up to the IkV range as listed in Table 3 8 An input zero operation is performed on each Multimeter range prior to performing the range verification measurements with the calibrator set to zero by range locking the calibrator in the range from which the output will be obtained 1 Select the required Multimeter range 2 On the calibrator set the output to zero Select OPERATE 3 Onthe Multimeter press the INPUT key and select Zero Rng to initiate the zeroing operation The Busy legend will appear and then extinguish when the zero operation has completed 4 Ontbhe calibrator select the value required for verification in the positive polarity 3 33 8508A Service Manual 3 34 5 Note the Multimeter s reading Compare the result with the allowable tolerance taking into account any known error from nominal of the calibrator for this output 6 Onthe calibrator select
135. to revert to the ranges menu HiV 2 Mode Calibration l AA 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 avoid electric shock when performing the following calibration procedures e Never touch any lead or terminal unless you are absolutely certain that no dangerous voltage is present e Make sure that signal leads are in a safe condition before you handle them in any way Press the Q Plus key and select HiVQ From the HiVQ menu select the 20 MQ range 2 Press the CONFIG key and select Filt and 4wQ 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 HiVQ mode Just one range can be calibrated if required but for a full calibration start with the 20 MQ range and work up to the 20 GQ range 3 23 8508A Service Manual For the 2 GQ range use the 1 GQ standard resistor in place of the calibrator To avoid the requirement for a 10 GQ standard the 20 GO range is automatically calibrated when the 2 GQ range gain calibration is triggered It is also necessary for the 100 MQ and 1 GQ NormalQ ranges to be calibrated prior to the 2 GQ HiVQ range for the result to be valid A 10 GQ standard resistor may be used for calibrating the 20 GQ range if available but i
136. tor range locked zero output 1 kQ 0 0000101 kQ 0 0000113 kQ 20 kQ 0 kQ Perform input zero operation to calibrator range locked zero output 10 kQ 0 000101 kQ 0 000113 kQ 200 kQ 0 kQ Perform input zero operation to calibrator range locked zero output 100 kQ 0 00101 kQ 0 00107 kQ 2 MQ 0 MQ Perform input zero operation to calibrator range locked zero output 1 MQ 0 0000117 MQ 0 0000142 MQ 20 MQ 0 MQ Perform input zero operation to calibrator range locked zero output 10 MQ 0 000320 MQ 0 000570 MQ 200 MQ 0 MQ Perform input zero operation to calibrator range locked zero output 100 MQ 0 01950 MQ 0 18700 MQ 2 GQ 0 GQ Perform input zero operation to calibrator range locked zero output 1 GQ 0 0018750 MQ 0 0018750 MQ 3 3 39 8508A Service Manual Table 3 10 Resistance Verification Points and Sequence cont 8508A Range Resistance Tolerance HIVO 20 MQ 0 GQ Perform input zero operation to calibrator range locked zero output 10 MQ 0 0000202 MQ 200 MQ 0 GQ Perform input zero operation to calibrator range locked zero output 100 MQ 0 0000870 MQ 2 GQ 0 GQ Perform input zero operation to calibrator range locked zero output 1 GQ 0 0003150 GQ 20 GQ 0 GQ Perform input zero operation to calibrator range locked zero output 1 GQ 0 012675 GQ 1 Based on 365 day Tcal 1 C 99 CL Absolute specifications See comments in Applicable Verification Tolerance se
137. two specifications in an RSS summation expressing the contributions in parts per million of the measured values For example making measurements of the ratio of 100 mV on the 200m VDC range and 100 V on the 200 VDC range applying the 365 day 1 C Absolute specifications 200 x 10 100 x 10 Making measurements on the same range will eliminate range to range errors such as drift since the time of calibration and improve the result When making measurements on the same range these errors will affect both measurements and effectively cancel leaving short term noise and linearity as the dominant errors The 20 minute Transfer Uncertainty Specifications are provided to describe the performance obtained when making ratio measurements on the same range The error in each measurement is evaluated by applying the relevant 20 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 specifications should be applied instead II I LEES 2 2 4 5 0 5x s 0 2 x a 7 37 ppm of the ratio For example making measurements of the ratio of 5 V and 10 V on the 20 VDC range applying the 20 minute Transfer Uncerta
138. ue On the Multimeter Press CAL to revert to CALIBRATION menu Select Set on the CALIBRATION menu Use the numeric keys with the SET VALUE menu to key in the true output value of the calibrator at the range gain value then press Enter Press SAMPLE to initiate the calibration operation Calibration is complete when the Busy legend goes out and the calibrated measurement is displayed On the Calibrator select the negative Range Gain point Output value Repeat steps 3 to 5 above to calibrate the negative Range gain point On the Calibrator set STANDBY 10 Press the DCI key to revert to the ranges menu AC Current Calibration AA 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 sure that signal leads are in a safe condition before you handle them in any way Initial Setup and Connections l 2 Press the ACI key and select the 200pA range 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 that this resolution and 100Hz Filter is used for calibration of all ACI ranges Reselect ACI Confirm that the Multimeter is configured for internal guard External Guard is deselected by checking that the Ext Grd legend
139. ure at which the 8508A is calibrated by Fluke during manufacture and service The 85084 is also capable of being calibrated at any temperature between 20 C and 25 C and the 1 C specifications will apply to operation within 1 C of that calibration temperature In the 8508A specification tables the temperature of calibration is referred to as TCal Specifications for 5 C are provided for situations where the 8508A is operated in environments with wider temperature 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 within that range The 8508A may be operated at temperatures between 0 C and 50 C but performance is not specified outside the range 5 C to 40 C Applying Temperature Coefficient Specifications The 85084 specification tables include information for the typical operating conditions of 1 C for calibration laboratories with tight temperature control and 5 C for calibration laboratories with looser temperature control or uncontrolled environments within that temperature range For the majority of applications choosing the Absolute specifications for the most

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