Tektronix Waterskis A6902B User's Manual
Contents
1. Before connecting any A6902B input probefs to a cir cuit under test ensure that the Maximum Working Voltage limits and the Channel Isolation Maximum Voltage limits will not exceed those values listed in the Specification Table 1 1 Figure 2 3 shows an example of how to connect an A6902B input probe Although this illustration shows the 3000 V probe it is equally applicable for any A6902B probe The common lead of the probe should always be con nected to the lowest impedance point usually circuit com mon in the circuit under test relative to the probe tip to obtain the most accurate waveform Whenever the type of input probe is changed for ex ample changing from the 3000 V probe to the 500 V probe a compensation adjustment must be made Refer to the Gain and Probe Compensation procedure in Operators Checks and Adjustments Section4 Figure 2 4 shows how the output BNC connectors are connected to an oscilloscope using the coaxial cables 2 4 Preparation For Use A6902B Whenever the type of input probe is changed for example changing from the 3000 V probe to the 500 V probe a compensation adjustment must be made Refer to the Gain and Probe Compensation procedure in Operators Checks and Adjustments Section 4 3 Figure 2 4 shows how the output BNC connectors are connected to an oscilloscope using the coaxial cables PROBE TIP N NOTE COMMON LEAD2. If both outputs of the A6902B are to be used at the same time both cables should be the same length 7 C ngth should not exceed two NOTE THE COMMON LEAD SHOULD BE CONNECTED and impedance Cable length should no TO THE LOWEST IMPEDANCE POINT IN THE meters and should be of 50 Q impedance Do not use CIRCUIT RELATIVE TO THE SIGNAL TO BE 3 any termination with the cables CHECKED 2931 06 Figure 2 3 Example of connecting an input probe i Preparation For Use A6902B 2 5 2 6 50 2 BNC CABLE CABLE LENGTH SHOULD NOT EXCEED 2 ME TERS UNLESS A 50 0 TERMINATION IS USED Ta CAUTION DO NOT USE ANY OSCILLOSCOPE PROBE FOR CONNECTING THE A6902B ISOLATOR TO AN OSCILLOSCOPE 5614 05 Figure 2 4 Connecting the A6902B outputs to an oscillo scope Preparation For Use A6902B CONTROLS CONNECTORS AND INDICATORS FRONT PANEL ZERO ADJ controls are used for adjusting the output DC level to zero volts with zero volts input to the A6902B Refer to Figure 3 1 for the location of items 1 through 5 NOTE 4 AC COMMON DC switches select the coupling between the input probe and the input stage of thelsolator in DC the input is directly coupled Only CHANNEL 2 controls items 2 through 5 and the in AC the input is connected to the Isolator POWER indicator item 1 are shown CHANNEL 1 through a capacitor and in COMMON the input controls are identical to CHANNEL 2 is conn
3. TEK OPERATOR Part No 070 5614 00 MANUAL Product Group 60 A6902B ISOLATOR Please Check for CHANGE INFORMATION at the Rear of This Manual First Printing JUL 1985 w Revised JUN 1986 Copyright 1985 Tektronix Inc All rights reserved Contents of this publication may not be reproduced in any form without the written permission of Tektronix Inc Products of Tektronix Inc and its subsidiaries are covered by U S and foreign patents and or pending patents TEKTRONIX TEK SCOPE MOBILE and are registered trademarks of Tektronix Inc TELEQUIPMENT is a registered trademark of Tektronix U K Limited Printed in U S A Specification and price change privileges are reserved TABLE OF CONTENTS LIST OF ILLUSTRATIONS o oooooooWoWoWomWo ol it LIST OF TABLES o oo ccc ec iie iii OPERATORS SAFETY SUMMARY sss iv SECTION 1 SPECIFICATION INTRODUCTION iste teet 14 ACCESSORIES PERFORMANCE CONDITION SECTION 2 PREPARATION FOR USE INSTALLATION POWER CORDS POWER REQUIREMENTS LINE VOLTAGE SELECTION CONNECTING THE A6902B ISOLATOR SECTION 3 CONTROLS CONNECTORS AND INDICATORS FRONT PANEL REAR PANEL A6902B Operators BOTTOM PANEL INPUT PROBES Setting Probe Tip Angles Changing input Probes Replacing Common Leads Replacing the 3000 V Probe Tip Removing the Side Pouches SECTION 4 OPERATOR S CHECKS AND ADJUSTMENTS
4. 240V NEMA 6 15 P ad pred IEC 83 15A Switzerland 220V 220v sev As 6A Abbreviations ANSI American National Standards Institute AS Standards Association of Australia 8S British Standards Institution CEE International Commission on Rules for the Approval of Electrical Equipment IEC International Electrotechnical Commission NEMA National Electrica Manufacturer s Association SEV Schweizevischer Elektrotechischer Verein 2931 21 Figure 2 1 Optional power cords and plugs LINE VOLTAGE SELECTION m IS S CAUTION aan an na m as This instrument may be damaged if operated with the Line Voltage Selection switch set for the wrong voltage or if the wrong line fuse is used The power input module located on the rear panel of the instrument houses a Line Voltage Selector two line fuses and a power cord connector The present line voi tage setting is indicated on the selector The range in line voltage covered by each position is given in Table 2 1 If it is necessary to convert the instrument for operation with a different line voltage perform the following procedure refer to Figure 2 2 1 Ensure that the power cord is disconnected from both the power source and the instrument and that both of the input probes and their common leads are disconnected from any electrical Source Preparation For Use A6902B 2 Using a flat bladed screwdriver pry out the Line Vol tage Selector Refer t
5. Two isolated channels that may be used at the same time either at different points in the same circuit or on separate circuits with different reference voltages Dc to 20 MHz bandwidth Plastic case and controls to provide a wide margin of operator safety Two output cables Section 1 A6902B 1 1 Two removable storage pouches for probes and cables Floating inputs that meet the reguirements of UL1244 IEC 348 and CSA Electronic Bulletin No 5568 ACCESSORIES Standard accessories provided with the A6902B in clude two input probes and two 72 inch coaxial cables for connecting the Isolator output to oscilloscope and other in strument inputs For more information on accessories 1 2 Specification A6902B used with the A6902B refer to the Accessories page at the rear of this manual PERFORMANCE CONDITIONS The electrical specifications listed in Table 1 1 are valid under the following conditions The A6902B Isolator was adjusted at an ambient temperature between 20 C and 30 C The ambient operating temperature is between 0 C and 50 C with a warm up period of at least 30 minutes Environmental characteristics are presented in Table 1 2 and the physical characteristics in Table 1 3 REV JUN 1986 Table 1 1 Electrical Characteristics Characteristic Performance Reguirement Supplemental Information Deflection Factor Sensitivity 20 mV div in a 1 2 5 seque
6. INTRODUCTION GAIN CHECK PROBE COMPENSATION oo 4 1 SECTION 5 APPLICATION EXAMPLE INTRODUCTION sees Bl EXAMPLE dist Seken tanah ea SECTION 6 OPTIONS AND ACCESSORIES OPTIONS cree an adu akan GET STANDARD ACCESSORIES OPTIONAL POWER CORDS OPTIONAL ACCESSORIES Figure 14 12 1 8 14 24 2 2 23 2 4 34 3 2 3 3 3 4 5 1 5 2 5 3 LIST OF ILLUSTRATIONS Page The AG902B ui bodo nana M MN vi Maximum working voltage between probe input and probe common ali temperatures 1 5 Maximum working voltage between probe common and earth ground Common lead feedthrough characteristics A6902B dimensional drawing Optional power cords and plugs Fuse holder line voltage selector eene Example of connecting an input Probe ee cette nese entere nnne nnne nennen Connecting the A6902B outputs to an oscilloscope sssssssseneenenenen n eene Front panel controls and indicator Rear and bottom panel controls connectors and labels Setting the 3000 V probe tip angle and replacing the common lead T Replacing the 3000 V probe tip issssssssseeeeeenenenennenne eene entenne entente nnne rententn nennen Application example test circuit sseesssssssseeeeeeenneeeer rennen nnne enne nennen nennen tnn Motor and gate waveforms at approximately 180 conduction seen Motor and gate waveforms at approximately 360 conduction oo ooooco oom A
7. Line voltage lt 115 V rms Add 0 6 mV p p per volt above 115 V DC Drift Temperature Coefficient 10 mV C or 0 1div C at output DC Balance 100 mV difference between any two VOLTS DIV switch settings Ambient temperature between 25 C and 50 C When operating at less than 25 C ZERO ADJ should be adjusted for the attenuator setting in use Range of ZERO ADJ Control z and 5 divisions from center Screen with oscilloscope set to 100 mV div vertical deflection factor Channel Isolation Maximum Voltage Using Two 3000 V Probes 6000 V dc peak ac 3000 V dc peak ac VDE Using Two 500 V Probes 1000 V dc peak ac REV JUN 1986 Specification A69028 Table 1 1 cont Characteristic Performance Reguirement Suppiemental Information e Eee Overdrive Recovery x 05 us to recover to within 1 division of initial location after removing overdrive signal the equivalent of up to amp 25 divisions regardless of the duration of the overdrive signal Delay Difference Between Two 4 ns from probe input to output BNC Typical delay from probe tip to Channels when used with an oscilloscope having a output BNC is 52 ns 1 M9 input resistance and up to 47 pF input capacitance and when both probes are same type and properly compensated Common Lead Signal 106 dB dc to 500 Hz from probe For above 500 Hz see Feedthrough input to ou
8. labe provides fuse replacement and line voltage information A6902B CAUTION FOR CONTINUED FRE PROTECTION REPLACE WITH SPECIFIED ZWN FYS Romina tine Fuse ney ozon yan 220 oteayise POWER MAX WATTS 28 FREQ 4 TO MOK POWER switch CHANNEL 2 CHANNEL 1 OUTPUT 4 VOLTS MAX P P CAUTION 5 TO AVOID ELECTRIC SHOCK DO NOT OPEN REFER SERVICING TO QUALIFIED SERVICE PERSONNEL 5614 07 Figure 3 2 Rear and bottom panel controls connectors and labels p REV JUN 1986 I EARTH GROUND CONNECTION is a standard banana plug connector attached to the Isolator chassis ground BOTTOM PANEL Refer to Figure 3 2 for the location of item 11 D CAUTION label warns operators not to open the A6902B case Controls Connectors And Indicators A6902B 3 3 3 4 INPUT PROBES SETTING PROBE TIP ANGLES The angle of the 500 V probe tip is continuously vari able and may be rotated to any desired position The angle of the 3000 V probe tip may be rotated in 90 increments if necessary to make it easier to attach the probe to the circuit under test To change the probe tip angle refer to Figure 3 3 and perform the following steps 1 Hold the probe with one hand placing your fore finger and thumb behind the slide to maintain the slide in the forward position 2 Loosen the collar by rotating it in the direction shown until it disenga
9. the cord storage lugs on the bottom of the A6902B Instruments are factory equipped with a standard 120 V power cord unless otherwise or dered Other power cords that can be used with the A6902B are shown in Figure 2 1 Part numbers for the power cords are listed in Accessories Section 6 For more information on power cords contact your Tektronix representative or your local Tektronix Field Office POWER REQUIREMENTS The A6902B is designed to be used with a three wire ac power system it operates from either a 120 V or a 240 V nominal power source from 48 to 440 Hz Before connecting the instrument to a power source verify that the Line Voltage Selector is set for the line voltage being used that the proper fuse is installed and that the line cord matches the power source to be used This pro cedure is described in the next paragraph and must be performed before operating the A6902B Refer to the Safety Summary in the front of this manual for power Source grounding and other safety considerations pertain ing to the use of this instrument Section 2 A6902B 2 1 Plug Line Reference Option Contiguration Usage Voltage Standards Number Nore ANS C73 11 American 420v NEMA 5 15 P Standard 120V IEC 83 15A Universal Euro CEE TANI 240V 240V lige gs a 10 16A UK 240V 240v an A2 13A 1 Australian 240V 240v AS C112 A3 10A Put ANS C73 20
10. z i fi x 300 1 x 300 V Bi 200v amp 200V a 100 V Yoo 50 V 50v 0 1 1 10 15 20 0 1 1 10 15 20 FREQUENCY MHZ FREQUENCY MHZ 5614 02 5614 03 Figure 1 1 Maximum working voltage between probe input Figure 1 2 Maximum working voltage between probe com and probe common all temperatures mon and earth ground IB Specification A6902B 1 5 Table 1 1 cont Characteristic Performance Requirement Supplemental information Aberrations 20 mV div to 2 V div 5 8 p p 0 3 C from 25 C 5 Vidiv to 10 V div 8 12 p p 0 3 C from 25 C 20 Vidiv 10 14 p p 0 3 C from 25 C Maximum dv dt 100 V ns 50 to 500 V div not specified Input Impedance With Probe Resistance 10 MQ 43 Nominal Capacitance Large Probe 3000 V 19 pF Smail Probe 500 V 19 pF Output Impedance 509 5 Output cable not 50 2 terminated cali brated on a 1 M9 oscilloscope input Common Mode Capacitance 100 pF nominai from probe common to earth ground 1 6 Specification A6902B REV JUN 1986 Table 1 1 cont Characteristic Performance Requirement Supplemental Information Tangential Sensitivity lt 20 mv Output Noise Switching Power Supply lt 20 mV p p supply noise plus ran dom noise 60 Hz Ripple lt 20 mV p p ripple noise plus random noise
11. 2 1 Hee leote ett 2931 12 Figure 5 2 Motor and gate waveforms at approximately Figure 5 3 Motor and gate waveforms at approximately 180 conduction 360 conduction 5 2 Application Example A6902B OPTIONS AND ACCESSORIES OPTIONAL ACCESSORIES STANDARD ACCESSORIES 2 Probes input 500 V with accessories 010 0411 15 2 Tips hook 013 0107 05 2 Sleeve ground cover 166 0404 01 2 Lead ground 195 1870 00 1 Fuse 0 3 A T SB Standard 159 0029 00 1 Fuse 0 15 A T SB Options A1 to A5 159 0054 00 1 Operator Manual 070 5614 00 2 Cables output 50 2 012 0204 00 1 Cable assembly power 161 0117 00 OPTIONAL POWER CORDS Option A1 Universal European 3 meters 161 0104 06 Option A2 United Kingdom 3 meters 161 0133 00 Option A3 Australia 3 meters 161 0135 00 Option A4 N American 3 meters 161 0134 00 Option A5 Switzerland 3 meters 161 0154 00 Service Manual 2 Probes input 3000 V BNC to probe tip Adapter for 3000 V probe BNC to probe tip Adapter for 500 V probe Banana to probe tip Adapter Kit for 3000 V probe Cable Marker Band White Cable Marker Band Green OPTIONS Includes 2 3 kV Probes 2 common leads includes 2 3 kV Probes 2 common leads 2 Banana to Probe Tip Adapters REV JUN 1986 Section 6 A6902B 070 5615 00 010 0409 01 015 0405 00 013 0084 02 013 0224 00 334 2
12. 2B Isolator is a two channel in strument which will permit safe floating measurements of voltages up to 3000 V dc peak ac above or below ground It substitutes for the vertical amplifier of an oscil loscope when either high voltage signals or small signals at a high voltage level are to be measured These signals are isolated from the oscilloscope by a combination of opt ical and transformer coupling This type of isolation to gether with the all plastic construction of the external con trols protects the operator from exposure to high voltage levels when making control settings on the A6902B front panel Voltage to be measured is applied between the A6902B input probe tip and its common lead When using ihe smaller probes supplied as standard accessories with the instrument the maximum differential voltage between channels is 1000 V dc peak ac With the larger probes supplied with Option 2 the maximum differential voltage between channels is 6000 V dc peak ac All measurements must be made with an oscilloscope having an input resistance of 1 MQ an input capacitance of up to 47 pF and a vertical deflection factor of 100 mV per divi Sion when necessary to use a connecting cable longer than that supplied an oscilloscope with a deflection factor of 50 mV division may be used in conjunction with a 509 termination An error in gain of up to 10 may result from the use of this method The A6902B features inciude
13. 6902B Operators Table 1 4 1 2 1 3 2 1 LIST OF TABLES Electrical Characteristics Lidah anna anna maan IN aminn Environmental Characteristics oiooooooooooooooooooo mo ooooooooo Lees Physlcal Characteristies oaa o defeat a cde umah NN sal Line Voltage Ranges nov cedet a eese dee bd tiu cet estas aste editi ie A6902B Operators Page 1 8 1 12 4 18 2 4 OPERATORS SAFETY SUMMARY The general safety information in this summary is for both operating personnel and servicing personnel Specific warnings and cautions will be found throughout the manual where they apply and do not appear in this summary TERMS in This Manual CAUTION statements identify conditions or practices that could result in damage to the equipment or other property WARNING statements identify conditions or practices that could result in personal injury or loss of life As Marked on Equipment CAUTION indicates either a personal injury hazard not immediately accessible as you read the marking or a hazard to property including the equipment itself DANGER or WARNING HIGH VOLTAGE indicates a personal injury hazard immediately accessible as you read the marking SYMBOLS As Marked on Equipment DANGER High voltage e Protective ground earth terminal PRECAUTIONS Power Source This product is intended to operate from a power source that does not apply more than 250 volts rms between the supply conductors A protectiv
14. 794 01 334 2794 07 Option 2 Option 9
15. Output Cable Length 1 8 m 6 ft Large Probe 3000 V Probe Cable Length 1 7m 5 5 ft Probe Head Length 200 mm 7 9 in Probe Common Lead Length 300 mm 11 8 in Specification A6902B REV JUN 1986 15 5 in 394 mm ae pa 1 5 2 in or T mm Figure 1 4 A6902B dimensional drawing 13 5 in C mem e 344 mm TETUR 2931 03A Specification A6902B PREPARATION FOR USE INSTALLATION Installation of the A6902B consists of verifying the proper power cord performing the Line Voltage Selec tion procedure connecting the input probe s to the cir cuit under test and connecting the output BNC connector s to an oscilloscope POWER CORDS The A6902B has a detachable three wire power cord with a three terminal polarized plug for connection to a power source The grounding termina of the plug is con nected directly to the instrument frame as recommended by national and international safety codes For electrical shock protection this plug should only be inserted into a power source socket that had a securely grounded protec tive ground contact Qualified service personnel should verify the protective ground system The power cord is detachable and when not in use should be wrapped around
16. The following is an example of one of the ways the TEK TRONIX A6902B Isolator might be used to look at high voltage signals or signals that are elevated to a high voltage level EXAMPLE The test circuit shown in Figure 5 1 is a simplified dia gram of a motor controller A variable RC network is used to trigger a diac which in turn triggers the gate of a triac In this example both channels of the A6902B may be used to compare the phase relationships of the gate signal to the motor voltage waveform and to the triac waveform For best performance the probe common leads should always be connected to the lowest possible impedance point relative to the probe tip In this case Channel 2 com mon would be connected to point A and Channel 2 input to point B to monitor the motor drive voltage The Channel 1 common lead should be connected to point C and the input REV JUN 1986 Section 5 A6902B to point D to monitor the triac gate waveform A typical waveform comparison is illustrated in Figure 5 2 Figures 5 2 and 5 3 show representative phase relation ships of gate drive and motor conduction for various motor control settings This type of measurement could not be made without the capability of floating the signal commons with the A6902B system SERIES MOTOR D 4p NEUTRAL 2931 10A Figure 5 1 Application example test circuit zem d CH2 CH
17. e ground connection by way of the grounding conductor in the power cord is essential for safe operation iv A6902B Operators Grounding the Product This product is grounded through the grounding conductor of the power cord To avoid electrical shock plug the power cord into a properly wired receptacle before con necting to the product input or output terminals A protec tive ground connection by way of the power cord is essen tial for safe operation An earth ground terminal is also provided on the rear panel Use the Proper Power Cord Use only the power cord and connector specified for your product Use only a power cord that is in good condition For detailed information on power cords and connec tors see Figure 2 1 and Accessories Section 6 in this manual Use the Proper Fuse To avoid fire hazard use only a fuse of the correct type voltage rating and current rating as specified in the parts list for your product Do Not Operate in Explosive Atmospheres To avoid explosion do not operate this product in an explosive atmosphere unless it has been specifically certified for such operation Do Not Remove Covers or Panels To avoid personal injury do not remove the product covers or panels Do not operate the product without the covers and panels properly installed A69028 Operators v f i The A6902B A6902B Operators 5614 01 SPECIFICATION INTRODUCTION The TEKTRONIX A690
18. ected to the electronic circuitry Common terminal within the Isolator COMMON is com parable to the GND position on a conventional POWER indicator is on whenever the Isolator is oscilloscope It connects the input to a refer energized ence level so the operator can set the position control VOLTS DIV switches establish the sensitivity of the oscilloscope isolator system The sensitivity is PROBE COMP controls are used to compensate adjustable from 20 mV division to 500 V division in a the input stages of the Isolator when the input 1 2 and 5 sequence probes are changed Li REV JUN 1986 Section 3 A6902B 34 VOLTS DIV WITH OSCILLOSCOPE SET AT BSK AC Denone comp bs COMMON sasa a 5614 06 Figure 3 1 Front panel controls and indicator Controls Connectors And Indicators REAR PANEL Refer to Figure 3 2 for the location of items 6 through 10 8 POWER SWITCH controis application of ac power to the Isolator An indicator light on the front panel is actuated when the power switch is in its on position 1 POWER CONNECTOR VOLTAGE SELECTOR allows the connection of the ac power cord to the Isolator The connector is an IEC connector and includes the Voltage Selector Indicator for alternative line voltage fully discussed in the Preparation For Use section of this manual OUTPUT VOLTAGE connectors make available the output of isolator Channels 1 and 2 9 CAUTION
19. ges from the probe body 3 While holding the probe tip pull back on the slide until the indexing guides on the shaft of the probe tip disengage from the guide slots in the probe body approximately one fourth inch 4 Rotate the probe tip to the desired position 0 90 80 or 270 5 Match the indexing guides with the correspond ing guide slots for the position chosen and push he slide forward until the indexing guides com pletely engage the probe slois 6 Thread the collar onto the probe body until the collar is snugly seated 7 The probe is now ready to be used CHANGING INPUT PROBES The input probes are attached to the instrument via coaxial connectors located inside the zippered pouch To remove an input probe grasp each connector one attached to the probe cable and one attached to the instrument cable and carefully disconnect them by pulling apart To Controls Connectors And Indicators A6902B PRESS TO RELEASE COMMON LEAD Figure 3 3 Setting the 3000 V probe tip angle and re placing the common lead install another input probe either 500 V or 3000 V as reguired align the two connectors and press them together until they snap into place and are firmly seated Whenever an input probe is changed the PROBE COMP control must be adjusted For these instructions refer to the Gain Check and Probe Compensation procedure in the Operator s Checks and Adjustments part of this ma
20. hannel 1 Siope sA Level Midrange POWER On Connect the PROBE ADJUST output to the oscil loscope Channel 1 input and set the oscilloscope Channel 1 Volts Division variable for exactly 5 divisions 6 Remove the connection between the PROBE AD JUST output and Channel 1 and center the trace vertically using the Position control 7 Connect the A6902B CHANNEL 1 output BNC connector to the oscilloscope Channel 1 BNC connector using the 50 N cable input 10 11 12 Use the A6902B ZERO ADJ control to position the os cilloscope trace on the center graticule line Set the A6902B AC COMMON DC switch to DC Connect the A6902B CHANNEL 1 input to the oscillo scope PROBE ADJUST output and connect the com mon lead clip to the oscilloscope ground Adjust the PROBE COMP control for the best flat top sguare wave CHECK That the oscilloscope display is 5 major divi sions 2 5 minor divisions 5 at approximately 1 kHz NOTE This display is based on the PROBE ADJUST out put of the TEKTRONIX 2235 Oscilloscope 500 mV at approximately 1 kHz with the A6902B VOLTS DIV control set for 0 1 V DIV If a different calibrator output voltage is used set the controls to maintain the same input output ratio and measure for 5 accuracy 13 Repeat parts 3 through 12 for CHANNEL 2 of the Operator s Checks And Adjustments A6902B A6902B REV JUN 1986 APPLICATION EXAMPLE INTRODUCTION
21. icators A6902B 3 7 OPERATOR S CHECKS AND ADJUSTMENTS INTRODUCTION By using the calibrator of an oscilloscope the gain and probe compensation of each channel can be checked and the probe compensation may be adjusted if necessary EQUIPMENT REQUIRED In addition to the isolator and its standard accessories the only other equipment necessary to make these checks is an oscilloscope with a vertical deflection of 100 mvV division an input impedance of 1 MQ an input capaci tance of less than 47 pF and a frequency response from dc to 100 MHz for example the TEKTRONIX 2235 NOTE An oscilloscope with a deflection factor of 50 mV division may also be used in conjunction with a 50 Q termination Detailed instructions for operating test equipment are not provided in this procedure Refer to the appropriate test equipment instruction manual if more information is needed GAIN CHECK AND PROBE COMPENSATION Ensure that the Line Voltage Selection procedure has been performed Connect the A6902B to the power input source press the POWER SWITCH to ON and allow 30 minutes for the A6902B to stabilize Set the A6902B CHANNEL 1 AC COMMON DC Switch to COMMON and the CHANNEL 1 VOLTS DIV switch to O 1 V Section 4 A6902B 4 1 4 2 4 Set the oscilloscope controls as follows VOLTS DIVM ne erecti M AC GND DC Vertical Channel 1 Triggering Mode Auto Coupling DC Source C
22. into the probe body as far as it will easily go PROBE TIP COLLAR COMMON LEAD 2931 17 nd Figure 3 4 Replacing the 3000 V probe tip Controls Connectors And Indicators A6902B 5 Thread the probe tip into the probe body until it 8 Thread the collar onto the probe body until the collar seats snugly is snugly seated 9 The probe is now ready for use 6 Move the slide forward to the position shown in Figure 3 3 and verify that there is approximately REMOVING THE SIDE POUCHES one eighth inch clearance between the indexing guides on the shaft of the probe tip and the threaded portion of the probe body If neces Where space is a consideration such as installing sary loosen the probe tip to achieve the correct the A6902B on a scope cart the side pouches may Clearance be removed To remove the side pouches first follow the pro cedure given in Changing Input Probes to remove 7 While holding the slide in the forward position align ihe probes The pouches may then be removed by the indexing guides with the guide slots in the probe unsnapping the four snaps holding them on the side body for the desired probe tip angle Press the probe of the instrument The probes should then be rein tip into the probe body until the indexing guides stalled on their original channel inputs to avoid the completely engage the guide slots need to readjust PROBE COMP Controls Connectors And Ind
23. nce with oscilloscope set to 100 mV div Accuracy 5 of indicated VOLTS DIV switch setting Maximum Working Voltage Large Probe 3000 V Probe Center Tip to Earth Ground 3000 V de peak ac 1500 V dc peak ac VDE Probe Center Tip to Probe Common 3000 V dc peak ac to 450 kHz 1500 V dc peak ac VDE For above 450 kHz see Figure 1 1 Probe Common to Earth Ground 3000 V dc peak ac to 250 kHz 1500 V dc peak ac VDE For above 250 kHz see Figure 1 2 REV JUN 1986 Specification A6902B T3 Table 1 1 cont Characteristic Performance Requirement Supplemental information Small Probe 500 V Probe Center Tip to Earth Ground 500 V dc peak ac Probe Center Tip to Probe Common 500 V dc peak ac to 3 MHz For above 3 MHz see Figure 1 1 Probe Common to Earth Ground 500 V dc peak ac to 6 MHz For above 6 MHz see Figure 1 2 Bandwidth 3 dB DC sal Doe eo ME 50 to 500 Vidiv not specified AC Coupled lt 5 Hz to z 20 MHz Rise Time x 17 5 ns 50 to 500 Vdiv not specified 1 4 Specification A6902B REV JUN 1986 3000 v 2000 V PROBE LI 3000 v 3000 V PROBE 1500 V 1500 V o 4 5 1000 V s ov e gt gt 500 V PROBE 5 5 s00v an oe 2 sov a
24. nual REPLACING COMMON LEADS To replace the common lead on the 500 V Probe grasp the end closest to the probe and pull straight away from the probe body install the new common lead by inserting the round end into the connector on the probe body To replace the common lead on the 3000 V Probe press and hold the release point shown in Figure 3 3 Pull the lead out of the probe body and remove pres sure from the release point Install the new common lead by pushing the lead end into the probe body until an audible click is heard Controls Connectors And Indicators A6902B 3 5 3 6 REPLACING THE 3000 V PROBE TIP To replace the 3000 V Probe tip with a new one refer to Figure 3 4 and perform the following steps 1 Loosen the collar by rotating it in the direction shown until it disengages from the probe body 2 Retract the siide to the position shown in Figure 3 4 The slide will stay in this position and the spring inside the probe tip should cause the probe tip to return to its original position if this does not occur hold the slide in the retracted position and pull the probe tip away from the probe body until it reaches its original position 3 Hold the probe body with one hand and rotate the probe tip in the direction shown until the probe tip completely disengages from the probe body 4 To install a new probe tip hold the probe body with the slide in the retracted position and insert the new probe tip
25. o Figure 2 2 3 From Table 2 1 determine the range for your aver age line voltage Opposite that range read the correct Line Voltage Selector position INDICATOR VU LINE VOLTAGE i n SETTING Em Table 2 1 Line Voitage Ranges Voltage Selector Fuse Size Switch Setting 110 120 Line Voltage Range 90 to 132 V 0 3A 250V 3AG SLOW 180 to 250 V 220 240 0 15A 250V 3AG SLOW 5614 04 Figure 2 2 Fuse holder line voltage selector Preparation For Use A6902B 2 3 NOTE Fuses for both line voltage settings are installed in the Line Voltage Selector when the instrument is shipped When the Selector is rotated to the desired setting the proper fuse is automatically installed in the circuit Confirm that both fuses are installed in the Selector 4 Rotate the Line Voltage Selector so the proper range lines up with the indicator on the frame of the power input module refer to Figure 2 2 and insert it back into the module WARNING This instrument is designed for operation from a power input source with its neutral at or very near earth ground potential with a separate safety earth conductor 5 Verify that your power cord matches the power source being used see Figure 2 1 6 Confirm that the POWER switch is set to OFF and connect the receptacle end of the power cord to the power input module CONNECTING THE A6902B ISOLATOR WARNING
26. scription Temperature Operating 0 C to 50 C Nonoperating Storage 55 C to 75 C Altitude Operating To 4 5 km 15 000 ft Nonoperating Storage To 15 km 50 000 ft Humidity Operating and Nonoperating Five cycles 120 hr total with equipment tested nonoperating to MIL STD 810C Method 507 1 at 90 to 95 Relative Humidity and at 30 C to 60 C Vibration Operating 0 64 mm 0 025 in p p 10 to 55 Hz sine wave Total time of test 75 minutes Shock 50 g half sine 11 ms duration for a total of 18 shocks Bench Handling Instrument will withstand a drop from approximately 100 mm 3 9 in at an angle of 45 Package Transportation Vibration 25 mm 1 in at 270 vpm Drop Package will withstand 10 drops from a height of 1 m 3 3 ft Specification A6902B Table 1 3 Physical Characteristics Table 1 3 cont Characteristic Description Characteristic Description Weight With Accessories 6 2 kg 13 7 Ib Dimensions cont Shipping Weight 80 kg 1777 Ib Small Probe 500 V Probe Cable Length 2m 66 ft Probe Head Length 64 mm 2 5 in Probe Common Lead Length 300 mm 11 8 in 133 mm 5 2 in Li Power Cable Length 3m 9 8 ft Dimensions See Figure 4 Isolator Height Width 394 mm 15 5 ind tengik 7 344 mm 13 5 in
27. tput BNC when used with Figure 1 3 Measured with an oscilloscope having a 1 MQ input VOLTS DIV switch set to resistance and up to 47 pF input 20 mV and AC COMMON DC capacitance Switch set in common position 1 8 Specification A6902B i i i i NOTE Common lead signal feedthrough can be further opti mized for a particular application Refer the instru ment to a qualified service technician z z o ao a x 9 5 o amp x E fe Ad ind a x ul 2 z o o o A 10 100 1 10 100 1 10 100 Hz Hz kHz kHz kHz MHz MHz MHz FREQUENCY 4642 04A Figure 1 3 Common lead feedthrough characteristics REV JUN 1986 Specification A6902B 1 9 Table 1 1 cont Characteristic Performance Reguirement an Supplemental Information Line Voltage Ranges rms Low 90 to 132 V High 180 to 250 V Line Frequency Range 48 to 440 Hz Power Consumption Maximum 24 W at 115 V 60 Hz Typical power consumption is 20 W Fuses for Line Voltage 0 30 A T SB 250 V 90 132 V range 0 15 A T SB 250 V 180 250 V range Interna Power Supply Voltages Ground Referenced Supply 7V 05V Ripple 10mV p p TV amp 05V Floating Supply 5V 4 05V Ripple lt 100 mV p p 5V 05V Specification A6902B It Table 1 2 Environmental Characteristics Characteristic De
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