Model 7154 2-Pole High Voltage Scanner Card
Contents
1. Input Isolation iaia 23 SECTION 4 Replaceable Parts Model 7154 Component Layout Model 7154 Schematic Diagram 29 4 2 SECTION 1 General Information 1 1 INTRODUCTION The Model 7154 is a 2 pole high voltage scanner card that switches signal levels up to 1100V 0 5A or 10VA peak 10mA at 1000V for resistive loads only Each of the 10 channels on the card consists of a double pole nor mally open 2 Form A relay with a user selectable shield or driven guard connection and a fused input The output connection and the input connections have screw terminals with a maximum allowable wire size of No 16 AWG A schematic representation is shown in Figure 1 1 a ved Figure 1 1 Model 7154 Simplified Schematic Switching is done in less than 2msec exclusive of the mainframe and the specified contact life is gt 10 closures with cold switching and gt 10 closures at maximum signal levels The relay drive current is 57mA relay The Model 7154 is field installable in an appropriate Keithley scanner mainframe e g Model 705 or Model 706 With the isolation between each channel being greater than 10 and less than 10pF each chan nel is well insulated from cross channel noise and interference 1 2 WARRANTY INFORMATION Warranty information is stated on the inside front cover of this manual If there is a need for ser2. 4 2 001 9S TIM Figure 4 1 Model 7154 Component Layout 27128 0 6c weeg 514 IPPON p ania rsa 6 12 v xa zus 1 2400 peices lecost so es c Gi RES GRO 3981700 HOIH i L azte Tiso wienn AYUMIION ABIHLISY annan 902 502 573005 40 HANH N NO SI LM sel Eu MH 99 T T 1 i 1 n T TT i I 2 2 hy 2 MT 3 TERI 3 ree 1 pres M 4 MN i E i i ota y 6x By lt 9 S 19 5 9 S iv lt 9 S 1 Li L ig T i i eed 7 ow et 1 Fani i zi i bes i i 1 i i E to B o5 i i EO 3 UP Sal 2 etu H i eros etes 106 9106 sS 9305 105 2105 145 0705 605 805 405 es bos 5 i i i 1 A 1 i i i i I i i i i 1 1 i 2 ti T T 1 H TA UA or A or or ar or sr sr j sr se Lisp A se A sr K sr H 1 9 2 H 9 E 1 9 H
3. Serial number Part description Circuit description if applicable Keithley part number 4 4 FACTORY SERVICE If the scanner card is to be returned to Keithley Instruments for repair perform the following 1 Photocopy and complete the service form at the back of this manual and include it with the card 25 2 Carefully pack the card in the original packing carton 3 Write ATTENTION REPAIR DEPARTMENT on the shipping label Note that it is not necessary to return the scanner mainframe with the card 4 5 COMPONENT LAYOUT AND SCHEMATIC DIAGRAM Figure 4 1 shows a component layout of the Model 7154 Figure 4 2 shows the schematic diagram of the Model 7154 Table 4 1 Model 7154 Replaceable Parts Circuit Keithley Desig ipti Part No Capacitor 104F 25V Aluminum Capacitor 0 14F 50V Ceramic Capacitor 0 014F 50V Ceramic Ferrite Bead Connector Connector Relay 2 Form A Fusible Link No 38 AWG Maguet Wire Jumper Upper Clamp Assembly 7055 303 15 Lower Clamp Assembly 7055 308 26 0 zd 2 WO3 TIHLGNI QOHlSdc91 Sxeg 9 80 5504 57 80 5504 61 80 5504 JO 901 NO TRISNI 8r J34 0 058 2 Hddtxee o sr tH OL RO Hos 3 B ano s 62 ca ae 0 1 0 9 2 e 8 a NO SRD 582 96 9r
4. 3 5 1 Channel Isolation This test measures the leakage current between two channels 1 2 20 Set up the equipment as shown in Figure 3 2 Set the scanner to channel 1 and the step mode Program channel 1 open and the other channels as closed CAUTION Make sure the channel under test is OPEN Failure to do this can cause damage to the instrument Set the electrometer to amps and zero check Program the Model 230 to output 100V Take the electrometer out of zero check The electrometer should read less than Due to the capacitance of the circuit the offset current may be high until the circuit capacitance is charged up Wait until the readings settle out Using Ohm s law calculate the channel isolation the leakage resistance between two channels For example 100V 10 A 1090 NOTE With the Model 617 electrometer in mode the resistance is calculated automatically Put the Model 230 in standby mode and set the electrometer to zero Repeat steps 2 through 6 for the remaining channels MODEL 7154 IN SCANNER MAINFRAME CHANNEL UNDER TEST 100V SOURCE Figure 3 2 Channel Isolation 21 3 5 2 Input Isolation This test measures the leakage current between a channel s HI and LO terminals 1 2 3 22 Set up the equipment as shown in Figure 3 3 Set the scanner to channel 1 and the step mode Close channel 1 and open all other channels Set t
5. 9 a 9 9 H 7 H 3 9 H 1 a m Jol usce ee A Pod as DI ne d e Pod Av 122 CU C EITHL Service Form Model No Serial No Date Name and Telephone No Company noe ER List all control settings describe problem and check boxes thal apply to problem Intermittent i Analog output follows display D Particular range or function bad specify failure Q Obvious problem on power up I Batteries and fusesareOK A Front panel operational A AN ranges or functions are bad J Checked all cables Display or output check one Drifts L Unable to zero A Unstable A Will uot read applied input I Overload Q Calibration only Certificate of calibration required C Data required atiach any additional sheets as necessary Show a block diagram of your measurement system including all instruments connected whether power is turned on or not Also describe signal source Where is the measurement being performed factory controlled laboratory out of doors etc What power line voltage is used __ Ambient temperature MEE Relative humidity EMPTUM Other Any additional information If special modifications have been made by the user p
6. are connected to the meter s LO If both GUARD pins can not be kept at the same potential remove the jumper CHANNELN JUMPER N 1 Jumper in or out depending on system grounding scheme Figure 2 3 Shielded Floating Measurement 11 2 6 2 Guarded Non driven guarded measurements are made with the set up shown in Figure 2 4 The jumper is installed to provide a guard which com pletely encloses high and low This guards them from other channels on the card for improved channel isolation JUMPER N 1 Guards High and Low from other citcultry Figure 2 4 Guarded Floating Measurement 2 6 3 Driven Guard If multiple sources are switched to a DUT using a driven guard as shown in Figure 2 5A the guard must be switched The jumper for each channel in use is removed so that the various sources will not try to drive other guards Instrument LO is not switched or is switched by another card for both Figures 2 5A and 2 5B LO and GUARD are shorted at both ends of the signal path to allow for the switched guard Low for the source s and DUT must be a con nection made externally 2 Figure 2 5B is the same configuration for connecting one source to multi ple DUTs In this case the jumper is removed to reduce the capacitive loading on the guard CHANNEL N B 1 N Guard driven by source no jumper Figure 2 5 Single Pole Switch with Switched Guard 2 6 4 4 Wire Connecting mult
7. current must be limited to 20mA I 10VA 500V and the limiting resistor calculation of Figure 2 1A would be R VII 500V 20mA 25kQ 2 Inductive Loads Inductive reaction voltage L di dt must be less than 1100V Typical clamping circuits are shown in Figure 2 2 Also consider the maximum load of 10VA when determining the voltage limit For example when switching 40mA the voltage must be limited to 250V V 10VA 40mA and the clamping resistor calcula tion of Figure 2 2A would be 250V 40mA 62500 LOAD THERMISTOR R LOAD HIGH RESISTANCE COLD LOW RESISTANCE HOT FAST THERMAL RECOVERY B THERMISTOR LIMITED Figure 2 1 Limiting Capacitive Reaction Current LOAD LOAD LOAD LOAD D RESISTOR CAPACITOR CLAMPED AC VOLTAGES 10 Figure 2 2 Limiting Inductive Reaction Voltage 2 6 APPLICATIONS The Model 7154 can monitor high voltages from 10 different devices under test DUT switch a high voltage source to 10 separate DUTs or connect multiple DUTs to multiple sources 2 6 1 Shielded CAUTION This application is one channel at a time Due to the possibility of high voltage be sure to break one connec tion before connecting another or the card could be damaged The measurement scheme shown in Figure 2 3 is used to make a shield ed floating measurement on up to 10 DUTs with one meter The guard traces are used as a shield so they
8. tests measuring leakage currents to check for a contaminated board and possibly bad relays Perform these tests in an environment within the specified operating temperature range 0 to 35 C up to 7096 RH of the scanner card WARNING Do not perform the procedures in this section unless you are a qualified service person Some of the pro cedures may expose you to potentially lethal voltages 30V RMS that could result in personal injury or death if normal safety precautions are not observed Recommended maintenance includes inspection of the scanner card and the card edge connector to ensure good electrical contact The Model 7154 does not require calibration 3 2 HANDLING AND CLEANING Because of the high impedance of the board take special care when handling and using to prevent degradation of performance Handle the board by the edges to avoid contaminating it with dirt body oil etc 17 To clean the board spray on an uncontaminated solvent such as Freon TMS or TE and clean with cotton swabs or a soft brush After the solvent has been applied and is still liquid blow dry the board with dry nitrogen gas 3 3 RECOMMENDED TEST EQUIPMENT Table 3 1 lists recommended test equipment for performance verifica tion Other test equipment may be substituted if specifications equal or exceed those stated NOTE The Model 617 electrometer has an internal 100V source If the Model 617 is used its internal voltage can be used
9. 200mQ initial 20 to rated life CONTACT POTENTIAL lt 35pV per contact pair with copper leads ACTUATION TIME 2ms exclusive of mainframe CHANNEL ISOLATION gt 10 Q lt 10pF INPUT ISOLATION Differential gt 10 Q 50pF Common Mode gt 10 Q 150pF COMMON MODE VOLTAGE 1100V peak OPERATING ENVIRONMENT 0 to 50 C up to 35 C at 70 STORAGE ENVIRONMENT 25 to 65 C DIMENSIONS WEIGHT 32mm high X 114mm wide X 272mm long 1 1 4 in x 4 1 2 in x 10 3 4 in Net weight 0 34kg 12 oz Specifications subject to change without notice TABLE OF CONTENTS SECTION 1 General Information 1 1 1 2 13 14 15 16 Introduction see RR Warranty Information 2 24 cerni ene tete Manual Addenda e yh weg 2 Safety Symbols and Terms 3 Unpacking and 1 3 Specifications 3 SECTION 2 Operation 2 1 2 2 23 24 2 5 2 6 2 61 2 6 2 2 6 3 2 64 Introduction EES Safety Penn WATE occ sac cris oer REAL Installation and Removal Operating Considerations Applications re dotes hk ress Shielded jes ieee ck ative aida SECTION 3 Servicing Info
10. Model 7154 2 Pole High Voltage Scanner Card Instruction Manual Contains Operating and Servicing Information KEITHLEY WARRANTY Keithley Instruments Inc warrants this product to be free from defects in material and workmanship for a period of year from date of shipment Keithley Instruments Inc warrants the following items for 90 days from the date of shipment prabes cables rechargeable batteries diskettes and documentation During the warranty period we will al our option either repair or replace any product that proves to be defective To exercise this warranty write or call your local Keilhley representative or contact Keithley headquarters in Cleveland Ohio You will be given prompt assistance and return instructions Send the product transportation prepaid to the indicated service facility Repairs will be made and the product returned transportation prepaid Repaired or replaced products are warranted for the balance of the origi nal warranty period or at least 90 days LIMITATION OF WARRANTY This warranty does not apply 10 defects resulting from product modification without Keithley s express written consent or misuse of any product or This warranty also does not apply to fuses software non rechargeable batteries damage from battery leakage problems arising from normal wear or failure to follow instructions THIS WARRANTY IS IN LIBU OF ALL OTHER WARRANTIES EXPRESSED OR IMPLIED INCLUDI
11. NG ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE THE REMEDIES PROVIDED HEREIN ARE BUYER S SOLE AND EXCLUSIVE REMEDIES NEITHER KEITHLEY INSTRUMENTS INC NOR ANY OF ITS EMPLOYEES SHALL BE LIABLE FOR ANY DIRECT INDI RECT SPECIAL INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE USE OF ITS INSTRUMENTS AND SOFTWARE EVEN IF KEITHLEY INSTRUMENTS INC HAS BEEN ADVISED IN ADVANCE OF THE POSSIBILITY OF SUCH DAMAGES SUCH EXCLUDED DAMAGES SHALL INCLUDE BUT ARE NOT LIMITED TO COSTS OF REMOVAL AND INSTALLATION LOSSES SUSTAINED AS THE RESULT OF INJURY TO ANY PERSON OR DAMAGE TO PROPERTY KEITHLEY Keithley Instruments Inc 28775 Aurora Road Cleveland OH 44139 216 248 0400 Fax 216 248 6168 http www keithley com CHINA Keithtey Instruments China Yuan Chen Xin Building Room 705 12 Yumin Road Dewai Madian Beijing China 100029 8610 2022886 Fax 8610 2022892 FRANCE Keithley Instruments SARL BP 60 3 all e dos Garays 91122 Palaiseau C dex 31 6 0115155 Fax 31 6 0117726 GERMANY Keithley Instruments GmbH Landsberger Strale 65 82110 Germering 49 89 849307 0 Fax 49 89 84930759 GREAT BRITAIN Keithley Instruments Ltd fhe Minster 58 Portman Road Reading Berkshire RG30 LEA 44 01734 575666 Fax 44 01734 596169 ITALY Keithley Instruments SRL Viale S Gimignano 38 20146 Milano 39 2 48303008 Fax 392 8302274 JAPAN Keithley KK Aibido Bldg 220 2 N
12. han 30V RMS 42 4V peak or 60VDC are present A good safety practice is to expect that hazardous voltage is present in any unknown circuit before measuring Before operating an instrument make sure the line cord is connected to a properly grounded power receptacle Inspect the connecting cables test leads and jumpers for possible wear cracks or breaks before each use For maximum safety do not touch the product test cables or any other instruments while power is applied to the circuit under test ALWAYS re move power from the entire test system and discharge any capacitors be fore connecting or disconnecting cables or jumpers installing or removing switching cards or making internal changes such as installing or removing jumpers Do not touch any object that could provide a current path to the common side of the circuit under test or power line earth ground Always make measurements with dry hands while standing on a dry insulated surface capable of withstanding the voltage being measured Do not exceed the maximum signal levels of the instruments and acces sories as defined in the specifications and operating information and as shown on the instrument or test fixture rear panel or switching card Do not connect switching cards directly to unlimited power circuits They are intended to be used with impedance limited sources NEVER connect switching cards directly to AC main When connecting sources to switch ing cards in
13. he electrometer to amps and zero check Program the Model 230 to output 100V Take the electrometer out of zero check The electrometer should read less than 10A Due to the capacitance of the circuit the offset current may be high until the circuit capacitance is charged up Wait until the readings settle out Using Ohm s law calculate the input isolation leakage resistance for this channel For example 100V 107A IPR NOTE With the Model 617 electrometer in V I mode the resistance is calculated automatically Put the Model 230 in standby made and set the electrometer to zero Repeat steps 2 through 6 for the remaining channels NOTE For all other channels the channel under test should be closed and all other channels open MODEL 7154 IN SCANNER MAINFRAME CHANNEL UNDER TEST G ELECTROMETER INPUT TRIAX 100V SOURCE Figure 3 3 Input Isolation 23 24 SECTION 4 Replaceable Parts 4 1 INTRODUCTION This section contains replacement parts information a component layout and a schematic diagram for the Model 7154 4 2 REPLACEABLE PARTS Table 4 1 lists parts alphanumerically in the order of their circuit designa tions 4 3 ORDERING INFORMATION To place an order or to obtain information about replacement parts con tact your Keithley representative or the factory See the back cover for addresses When ordering include the following information Model number
14. in place of the Model 230 Voltage Source Table 3 1 Recommended Test Equipment Model Scanner Mainframe Keithley 705 or 706 Extender Card Keithley 7061 DMM lt 0 10 sensitivity Keithley 196 Voltage Source 100VDC Keithley 230 Electrometer 10 A Keithley 614 or 617 3 4 CONTACT RESISTANCE TEST This test measures the resistance of each relay contact in an opened and closed state 1 Set up the equipment as shown in Figure 3 1 Short the HI terminal to the LO terminal of each channel Attach two copper wires to the output HI and LO terminals 2 Zero the Model 196 with the Kelvin test leads shorted together 18 3 Set the channel mainframe to the channel mode channel 1 and the step mode Close channel 1 from the scanner front panel The reading on the Model 196 should indicate a short circuit less than 0 2 4 Open channel 1 from the scanner front panel The reading on the Model 196 should indicate an open circuit gt 0 5 Repeat steps 3 and 4 for the remaining channels on the card MODEL 7154 IN SCANNER MAINFRAME CHANNEL UNDER TEST OUTPUT HI io KELVIN TEST LEADS M OHMS VOLTS SES d OHMS Figure 3 1 Contact Resistance 3 5 ISOLATION TESTS The two isolation tests measure leakage currents for calculating leakage resistances on the Model 7154 With the Model 7061 Universal Adpater Card these tests can be performed faster 19
15. iple DUTs to one instrument using either a Kelvin technique or external sense as with a Source Measure Unit SMU re quires two cards operating in 4 pole mode This is shown in Figure 2 6 HI and Sense HI are switched through one card The jumper is install ed to provide a guard all the way to the DUT Since this is a driven guard it is connected only to the guard of the instrument and not ter minated at the DUT LO and Sense LO are switched through the second card The jumper is installed to provide shielding for these lines The shield on the cabl ing should cover as much of the signal lines as possible and should be terminated only at the instrument Shields are typically at circuit low or earth This configuration combines sense and Kelvin configurations so that guard on the card is driven for the High leads and is a shield for the Low leads 14 One instrument to N OUTs only and only one relay per card closed at a time This connection not always made Il may not be required high current levels Connected at card end only not at OUT Figure 2 6 Source with External Sense or Kelvin Measurement 15 16 SECTION 3 Servicing Information 3 1 INTRODUCTION This section describes tests for verifying the performance of the Model 7154 The tests include Functionality test Measuring contact resistance to check for open or shorted relays or bad connections Specification tests Two isolation
16. is 10 channel card set the scanner to the 2 pole mode when using the Model 7154 by itself or when intermixing with other 10 channel cards In the 2 pole scanner mode each scanner chan nel controls one channel on one 10 channel card The 4 pole mode of operation will be discussed in Section 2 6 Signal Levels The maximum signal levels for the Model 7154 2 Pole High Voltage Card are 1100V maximum 0 5A or 10VA peak for resistive loads only The specified contact life is gt 10 closures with cold swit ching and gt 10 closures at maximum signal levels WARNING When switching signals greater than 30V RMS or 42 2V peak take care to prevent contact with live circuits which could cause electrical shock resulting in injury or death Cabies Shielded cables should be used with the Model 7154 card when switching above 50V The shield should be connected to the circuit LO or GUARD This prevents excessive radiation from the cables from in terfering with any equipment The cables must be rated for greater than 1100V Fusible Links The Model 7154 scanner card has a fusible link Q1 5Q20 in series with the high and low input side of each chan nel s relay A link opens when the current level on that channel becomes excessive because of an external circuit misapplication or a relay failure The links protect the PC board from damage that is difficult to repair e g lifted or burned traces on the board A repair procedure for the links fo
17. ishishinjuko Shinjuku ku Tokyo 160 81 3 5389 1964 Fax 81 3 5389 2068 NETHERLANDS K eit ley Instromeats BV Avelingen West 49 4202 MS Gorinchem 31 0 R3 635333 Fax 31 40 183 630821 SWITZERLAND Keithley Instruments SA Kriesbachstrasse 4 8600 Dubendort 41 1 8219444 Fax 41 t 8203081 TAIWAN Keithley Instruments Taiwan 1 Ming Yu First Street Hsinchu Taiwan R O C 886 35 778462 886 35 778455 Model 7154 2 Pole High Voltage Scanner Card Instruction Manual 1988 Keithley Instruments Inc Test Instrumentation Group Ali rights reserved Clevetand Ohio U S A March 1988 First Printing Document Number 7154 901 01 Rev A SAFETY PRECAUTIONS The following safety precautions should be observed before using this product and any associated instrumentation Although some instruments and accessories would normally be used with non hazardous voltages there are situations where hazardous conditions may be present This product is intended for use by qualified personnel who recognize shock hazards and are familiar with the safety precautions required to avoid possible injury Read the operating information carefully before us ing the product Exercise extreme caution when a shock hazard is present Lethal voltage may be present on cable connector jacks or test fixtures The American National Standards Institute ANSI states that a shock hazard exists when voltage levels greater t
18. lease describe Be sure to include your name and phone number on this service form IKEI T HLEY Keithley Instruments Inc Test Instrumentation Group 28775 Aurora Road Cleveland Ohio 44139 Printed in the U S A
19. llowing items are shipped with every Model 7154 Model 7154 2 Pole High Voltage Scanner Card Model 7154 Instruction Manual 1 6 SPECIFICATIONS Detailed specifications of the Model 7154 precede the Table of Contents of this manual 3 4 SECTION 2 Operation 2 1 INTRODUCTION This section provides information needed to use the Model 7154 2 Pole High Voltage Card with the Models 705 and 706 scanner mainframes Once the card is installed in the mainframe refer to the mainframe in struction manual for complete operating instructions 2 2 SAFETY PRECAUTIONS WARNING User supplied lethal voltages may be present on the PC board or the connections Turn off all power and discharge stored energy in external circuitry before mak ing or breaking connections 1 Do not exceed the Model 7154 maximum voltages of peak terminal to terminal and 1100V peak any terminal to chassis 2 Make sure the scanner mainframe is grounded through an earth grounded receptacle before operation 3 Inspect all test lead connections for wear and defects such as cracks and exposed wires 4 Use appropriately rated cables when switching high voltages 2 3 WIRING Each channel on the Model 7154 card consists of a double pole nor mally open 2 Form A switching relay The Model 7154 will switch any one of the 10 signals inputs to one output or switch one signal to any one of 10 outputs See Figure 1 1 ww NOTE Because of the high impeda
20. llows 1 Clean out the PC board feedthru holes for the fusible link with a desoldering tool 2 Insert a jumper of No 38 AWG magnet wire into the holes and solder in place CAUTION This wire must be taut to maintain voltage spacing CAUTION When replacing the fusible links use only No 38 AWG magnet wire Use of any other wire may cause severe damage to the PC board 3 Check the same channel s relay contacts for a short or insufficient input isolation resistance and replace the relay if necessary See Sec tions 3 and 4 4 Clean the PC board according to the instructions given in paragraph 3 2 Depending on your application a current limiting resistor can be used in place of a fusible link Each resistor will limit the current flow through one side HI or LO of one channel The resistors must be of sufficient power rating to safely dissipate any overload Reactive Loads The Model 7154 is specified for resistive loads only Since reactive loads can cause excessive currents and voltages current surge limiting for capacitive loads and voltage clamping for induc tive loads are required to prevent damaging the relays and external circuitry 1 Capacitive Loads The surge current from a capacitive load must be less than 0 5A to protect the relays Figure 2 1 shows typical cir cuits to limit current surges Also consider the maximum load of 10VA when determining the current limit For example when switch ing 500V the
21. nce of the board take special care when handling and using to prevent degradation of performance Handle the board by the edges to avoid con taminating it with dirt body oil etc For cleaning instruc tions see paragraph 3 2 Wiring is accomplished by means of terminal strips as shown on the component layout see Figure 4 1 Each channel has a HI connec tion LO connection and GUARD connection Guard is common to all channels with the jumpers W1 W10 installed The Model 7154 is shipped with all jumpers installed Resistance of the relay contacts path is less than 0 20 A common guard surrounds all analog signal paths Use wires or cables that are rated for greater than 1100V The maxi mum allowable wire size is No 16 AWG The minimum wire size is No 26 AWG Route the wires through the rubber clamp pads located at the rear of the card 2 4 INSTALLATION AND REMOVAL Once the card is wired insert it card edge first into the scanner main frame by aligning it with the grooves in the appropriate slot Make sure it is properly seated into the mainframe connector Push the locking tabs forward to the center of the card to lock it in To remove a card first turn off the mainframe and all other equipment connected to the card Unfasten the locking tabs on the card by pull ing the tabs outward Grasp the end of the card and carefully pull it out of the mainframe 2 5 OPERATING CONSIDERATIONS Since the Model 7154
22. rmation 3 1 3 2 3 3 34 3 5 3 5 1 3 5 2 Introduction sseeee mmm Handling and Cleaning eee nee Recommended Test Contact Resistance Test en Isolation Tests Le hmm hr Channel Isolation sese nnn Input 1 ee SECTION 4 Replaceable Parts 41 4 2 43 44 4 5 Introduction emm 25 Replaceable Parts 25 Ordering Information 25 Factory Service 00 0 25 Component Layout and Schematic Diagram LIST OF TABLES SECTION 3 Servicing Information 34 Recommended Test SECTION 4 Replaceable Parts 4 1 Model 7154 Replaceable Parts iii iv LIST OF ILLUSTRATIONS SECTION 1 General Information 14 Model 7154 Simplified SECTION 2 Operation 2 1 2 2 3 4 5 6 NNN h2 Limiting Capacitive Reaction Limiting Inductive Reaction Shielded Floating Measurement Guarded Floating Single Pole Switch with Switched Guard Source with External Sense or Kelvin Measurement SECTION 3 Servicing Information 3 1 3 2 3 3 4 1 Contact Resistance Li Channel 1 0
23. stall protective devices to limit fault current and voltage to the card When fuses are used in a product replace with same type and rating for continued protection against fire hazard Chassis connections must only be used as shield connections for measur ing circuits NOT as safety earth ground connections If you are using a test fixture kecp the lid closed while power is applied to the device under test Safe operation requires the use of a lid interlock If a screw is present on the test fixture connect it to safety earth ground using 18 AWG or larger wire The symbol on an instrument or accessory indicates that 1000V or more may be present on the terminals Refer to the product manual for de tailed operating information Instrumentation and accessories should not be connected to humans Maintenance should be performed by qualified service personnel Before performing any maintenance disconnect the line cord and all test cables SPECIFICATIONS CHANNELS PER CARD 10 CONTACT CONFIGURATION 2 pole Form A with user selectable shield or driven guard Each pole is fused using No 38 AWG magnet wire CONNECTOR TYPE Screw terminals No 16 AWG maximum RELAY DRIVE CURRENT 57mA per relay typical MAXIMUM SIGNAL LEVEL 1100V peak 0 5A rms switched 1 0A rms carry 10VA resistive load only CONTACT LIFE gt 10 closures cold switching gt 5 x 10 closures at maximum signal levels CONTACT RESISTANCE lt
24. vice contact the Keithley representative or authorized repair facility in your area Check the back cover for ad dresses The service form supplied at the end of the manual should be used to provide the service facility with information concerning any difficulty 1 3 MANUAL ADDENDA Product improvements or changes to this manual will be explained on an addendum included with the manual It is recommended that this information be incorporated immediately into the appropriate places in the manual If an additional instruction manual is required order the manual package Keithley Part Number 7154 901 00 The manual package in cludes an instruction manual and all pertinent addenda 1 4 SAFETY SYMBOLS AND TERMS The symbol on card denotes that user should refer to the operating instructions The symbol denotes that a high voltage may be present on the terminals The WARNING used in this manual explains dangers that could result in personal injury or death The CAUTION used in this manual explains hazards that could damage the instrument 1 5 UNPACKING AND INSPECTION The Model 7154 was inspected both electrically and mechanically before shipment Upon receiving the Model 7154 unpack all items from the shipping carton and check for any obvious damage that may have oc curred during transit Report any damage to the shipping agent Re tain and use the original packaging materials in case reshipment is necessary The fo
Download Pdf Manuals
Related Search