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Card Connections and Installation

2-17

For 4-pole operation, connect OUT A HI (red) to INPUT HI and connect OUT A LO (black) 

to INPUT LO. Also connect OUT B HI (red) to SENSE HI and connect OUT B LO (black) to 
SENSE LO. See 

Figure 2-11

.

NOTE

Be sure to select the rear inputs with the multimeter front panel INPUTS switch when 
using the scanner.

Figure 2-11

4-pole output connections

Scanner card removal

Perform the following steps to remove the scanner card from the multimeter:

WARNING

Turn off power to all instrumentation (including the multimeter) and 
disconnect all line cords. Make sure all power is removed and any stored 
energy in the external circuitry is discharged.

 

1.

Unlock the card by pulling the ejector arms outward.

2.

Carefully slide the card out of the multimeter.

3.

Install the cover plate over the OPTION SLOT and secure with the two fasteners if the 
multimeter is to be operated without the scanner card installed.

Input HI

Out A

HI (Red)

Input LO

Out B

LO (Black)

Out A

LO (Black)

Sense HI

Sense LO

Out B

HI (Red)

Содержание 2000-SCAN-20

Страница 1: ...Model 2000 SCAN 20Scanner Card Instruction Manual A G R E A T E R M E A S U R E O F C O N F I D E N C E ...

Страница 2: ...Model 2000 SCAN 20 Scanner Card Instruction Manual 1997 Keithley Instruments Inc All rights reserved Cleveland Ohio U S A Third Printing July 2003 Document Number 2000 20 901 01 Rev C ...

Страница 3: ...numbered sequentially When a new Revision is created all Addenda associated with the previous Revision of the manual are incorporated into the new Revision of the manual Each new Revision includes a revised copy of this print history page Revision A Document Number 2000 20 901 01 February 1998 Revision B Document Number 2000 20 901 01 June 1998 Revision C Document Number 2000 20 901 01 July 2003 A...

Страница 4: ...onnected to mains voltage or to voltage sources with high transient over voltages Measurement Category II connections require protection for high transient over voltages often associated with local AC mains connections Assume all measurement control and data I O connections are for connection to Category I sources unless otherwise marked or described in the Manual Exercise extreme caution when a s...

Страница 5: ... these voltages The symbol indicates a connection terminal to the equipment frame The WARNING heading in a manual explains dangers that might result in personal injury or death Always read the associated information very carefully before performing the indicated procedure The CAUTION heading in a manual explains hazards that could damage the instrument Such damage may invalidate the warranty Instr...

Страница 6: ... 1 4 Repacking for shipment 1 4 Optional accessories 1 5 2 Card Connections and Installation Introduction 2 2 Handling precautions 2 2 Connections 2 3 Connection precautions 2 3 Card configuration 2 4 Card connectors 2 5 Typical connecting schemes 2 8 Voltage connections 2 8 Resistance connections 2 9 Current measurements 2 11 Card installation and removal 2 14 Scanner card installation 2 14 Outpu...

Страница 7: ...urrent measurements 3 11 Measurement considerations 3 12 Path isolation 3 12 Magnetic fields 3 13 Electromagnetic interference EMI 3 13 Ground loops 3 14 Keeping connectors clean 3 15 4 Service Information Introduction 4 2 Handling and cleaning precautions 4 2 Handling precautions 4 2 Soldering precautions 4 3 Performance verification 4 3 Environmental conditions 4 3 Recommended equipment 4 4 Path...

Страница 8: ...5 Replaceable Parts Introduction 5 2 Parts list 5 2 Ordering information 5 2 Factory service 5 2 Component layout and schematic diagram 5 3 A Specifications ...

Страница 9: ...11 4 pole output connections 2 17 3 Operation Figure 3 1 2 wire resistance test connections 3 9 Figure 3 2 4 wire resistance test connections 3 10 Figure 3 3 Connections for current measurements 3 11 Figure 3 4 Path isolation resistance 3 12 Figure 3 5 Voltage attenuation by path isolation resistance 3 13 Figure 3 6 Power line ground loops 3 14 Figure 3 7 Eliminating ground loops 3 15 4 Service In...

Страница 10: ...r J1036 pin designations 2 7 Table 2 2 Output connector J1035 pin designations 2 7 3 Operation Table 3 1 Summary of SCPI scanner commands 3 8 4 Service Information Table 4 1 Recommended verification equipment 4 4 5 Replaceable Parts Table 5 1 Model 2000 SCAN 20 parts list 5 3 ...

Страница 11: ......

Страница 12: ...1 General Information General Information ...

Страница 13: ...nual addenda Safety symbols and terms Specifications Unpacking and inspection Repacking for shipment Optional accessories Features The Model 2000 SCAN 20 is a scanner card designed to be installed in the Model 2000 20 Multimeter The Model 2000 SCAN 20 is not designed for the Models 2000 or 2010 Multimeters Key features include Twenty channels of 2 pole relay input Channels configurable for 4 pole ...

Страница 14: ...to avoid personal contact with these voltages The WARNING heading used in this manual explains dangers that might result in personal injury or death Always read the associated information very carefully before performing the indicated procedure The CAUTION heading used in this manual explains hazards that could damage the scanner card Such damage may invalidate the warranty Specifications Model 20...

Страница 15: ...Card Model 2000 20 901 00 Instruction Manual Test lead set for output connections two red two black Additional accessories as ordered Instruction manual If an additional Model 2000 SCAN 20 Instruction Manual is required order the manual package Keithley part number 2000 20 901 00 The manual package includes an instruction manual and any pertinent addenda Repacking for shipment Should it become nec...

Страница 16: ... This 2m or 4m cable assembly is terminated with a DB44 female connector on one end and is unterminated at the other end The female end mates to the male DB44 connector on the scanner card Model 2000 MTCD 2 Cable Assembly This 2m cable assembly is terminated with a DB44 female connector on one end and a DB50 male connector at the other end The female end mates with the scanner card ...

Страница 17: ...1 6 General Information ...

Страница 18: ...2 CardConnections andInstallation CardConnec tionsand Installation ...

Страница 19: ...ical connection schemes Provides some typical connection schemes for 2 pole and 4 pole operation Card installation and removal Summarizes the procedure to install the scanner card in a multimeter outlines scanner card output connections and describes how to remove the card Handling precautions To maintain high impedance isolation between channels take care when handling the scanner card to avoid c...

Страница 20: ... serious injury or death adhere to the following safety precautions Before making or breaking connections to the scanner card make sure the DMM power is turned off and power is removed from all external circuitry Do not connect signals that will exceed the maximum specifications of the scanner card If both the front panel terminals and the scanner card terminals are connected at the same time the ...

Страница 21: ...through 10 and the OUT B HI and LO connections are for channels 11 through 20 4 pole paired channels are as follows Channels 1 and 11 Channels 2 and 12 Channels 3 and 13 Channels 4 and 14 Channels 5 and 15 Channels 6 and 16 Channels 7 and 17 Channels 8 and 18 Channels 9 and 19 Channels 10 and 20 Figure 2 1 Model 2000 SCAN 20 simplified schematic HI LO Channel 1 HI LO Channel 2 9 Channel 10 HI LO C...

Страница 22: ...Table 2 1 and Table 2 2 respectively The J1035 connects to a plug that has four separate test leads These test leads connect to the rear HI and LO INPUT and SENSE jacks on the multimeter Refer to Output connections to multimeter on page 2 16 for more information NOTE It is not necessary to connect the OUT B leads for 2 pole mode operation The J1036 connects to a DB44 mass terminated connector Figu...

Страница 23: ... Channel 6 20 HI 5 LO Channel 7 37 HI 38 LO Channel 8 27 HI 12 LO Channel 9 30 HI 15 LO Channel 10 2 HI 1 LO Channel 11 21 HI 6 LO Channel 12 24 HI 9 LO Channel 13 41 HI 42 LO Channel 14 18 HI 3 LO Channel 15 35 HI 36 LO Channel 16 25 HI 10 LO Channel 17 28 HI 13 LO Channel 18 19 HI 4 LO Channel 19 22 HI 7 LO Channel 20 NOTE The HI and LO input channel pin designations correspond to connector J103...

Страница 24: ...2 HI 21 Channel 2 LO 14 Channel 12 LO 6 Channel 3 HI 33 Channel 13 HI 24 Channel 3 LO 34 Channel 13 LO 9 Channel 4 HI 23 Channel 14 HI 41 Channel 4 LO 8 Channel 14 LO 42 Channel 5 HI 39 Channel 15 HI 18 Channel 5 LO 40 Channel 15 LO 3 Channel 6 HI 43 Channel 16 HI 35 Channel 6 LO 44 Channel 16 LO 36 Channel 7 HI 20 Channel 17 HI 25 Channel 7 LO 5 Channel 17 LO 10 Channel 8 HI 37 Channel 18 HI 28 C...

Страница 25: ...re used in the 2 pole mode and that up to 20 voltage sources can be switched with this configuration This basic configuration can be used for the following types of measurements DCV ACV Frequency voltage only All channels 1 through 20 can be used with this configuration Figure 2 4 Connections for voltage scanning CH 1 CH 20 V HI LO V HI LO To DMM Input HI LO 2000 SCAN 20 Card Voltages Under Test H...

Страница 26: ...hows typical 2 pole resistor test connections The 2 pole resistance configuration can be used to test up to 20 DUTs Figure 2 5 Typical connections for 2 wire resistance scanning CH 1 CH 20 To DMM Input HI LO 2000 SCAN 20 Card Resistors Under Test HI LO HI LO OUT A OUT B HI LO HI LO J1036 J1035 ...

Страница 27: ...ral configuration can be used with all channels to scan 4 wire resistance measurements Figure 2 6 Typical connections for 4 wire resistance scanning HI LO HI LO HI LO HI LO HI LO HI LO HI LO CH 1 CH 2 CH 10 CH 11 CH 12 CH 20 OUT A To DMM Input 2000 SCAN 20 Card Resistors Under Test HI LO HI LO OUT B To DMM Sense HI LO J1036 J1035 ...

Страница 28: ... user installable current shunts Location R103 is for channel 11 and location R104 is for channel 1 Figure 2 7 Current shunt locations Recommended current shunt values Hole spacing on the circuit board is intended for 1 10W resistors The resistance value will depend on the current you intend to measure 1kΩ resistors should be optimum for many appli cations A 1kΩ resistor will allow you to switch c...

Страница 29: ...th pure methanol and allow the board to dry for several hours in a 50 C environment before use Current measurements Even with the current shunts installed you cannot make direct current measurements with the scanner card Instead you must close the channel to be measured and measure the voltage across the shunt The current can then be calculated as follows I V R Where I current being determined V v...

Страница 30: ...only channels 1 and 11 have current shunts installed This configuration can be used to scan the following DC current AC current Figure 2 8 Current connections HI LO HI LO HI LO HI LO HI LO HI LO HI LO CH 1 CH 2 CH 10 CH 11 CH 12 CH 20 OUT A To DMM Input 2000 SCAN 20 Card AC or DC Current HI LO HI LO OUT B J1036 J1035 A A AC or DC Current NOTE Current shunts must be installed for channels 1 and 11 ...

Страница 31: ...owing steps and refer to Figure 2 9 to install the card assembly in the multimeter WARNING Turn off power to all instrumentation including the multimeter and disconnect all line cords Make sure all power is removed and any stored energy in the external circuitry is discharged 1 Pry out the two fasteners holding the OPTION SLOT cover plate to the rear panel of the multimeter Remove the cover plate ...

Страница 32: ...Card Connections and Installation 2 15 Figure 2 9 Card installation Unlock Card Ejector Arms 2 Lock Card NOTE Card connections are removed for clarity ...

Страница 33: ...nnot exceed the ratings of the scanner card as long as the scanner card output leads are connected to the multimeter rear panel input jacks For 2 pole operation connect OUT A HI red to INPUT HI and connect OUT A LO black to INPUT LO See Figure 2 10 NOTE Be sure to select the rear inputs with the multimeter front panel INPUTS switch when using the scanner Figure 2 10 2 pole output connections Input...

Страница 34: ... following steps to remove the scanner card from the multimeter WARNING Turn off power to all instrumentation including the multimeter and disconnect all line cords Make sure all power is removed and any stored energy in the external circuitry is discharged 1 Unlock the card by pulling the ejector arms outward 2 Carefully slide the card out of the multimeter 3 Install the cover plate over the OPTI...

Страница 35: ...2 18 Card Connections and Installation ...

Страница 36: ...3 Operation Operation ...

Страница 37: ...commands necessary to control the scanner card using the Model 2000 20 Multimeter Typical applications Discusses typical applications for the Model 2000 SCAN 20 Measurement considerations Discusses a number of measurement considerations to take into account when using the scanner NOTE Before using the Model 2000 SCAN 20 scanner card you should be thoroughly familiar with the operation of the multi...

Страница 38: ...l generate a Missing hardware error and front panel operations pertaining to the scanner will inform you that no scanner is present Scanner option bus query OPT is an IEEE 488 2 common query that determines whether or not a scanner card is installed Also the Model 2000 20 multimeter can distinguish between a Model 2000 SCAN 10 channel card and the Model 2000 SCAN 20 20 channel card The response to...

Страница 39: ...ng a different channel from the one presently closed will cause the closed channel to open and allow a settling time before closing the selected channel NOTE For channels 11 through 20 more than one channel annuciator is lit For example CH1 and CH10 are lit for channel 11 and CH1 CH9 and CH10 are lit for channel 20 3 The and keys alone will also close the channels Press the and keys until the chan...

Страница 40: ...ommand PRINT 1 output 16 route multiple open 1 3 5 NOTE Opening channel 21 selects the 2 pole operating mode Selecting measurement function Use the following procedure to select a specific measurement function for an internal channel 1 Use the and keys to select the desired channel 2 Select the desired measurement function with the keys on the front panel The various measurement functions availabl...

Страница 41: ...llowing message MAX CHAN 20 Use the and keys to select the channel at which the scanning will stop and press ENTER 4 The instrument will display the following message TIMER OFF Use the or key to select the ON option if desired and press ENTER Select the scan time when prompted and press ENTER 00H 00M 01 000S 5 The unit will display the following message RDG CNT 0020 Use the and keys to select the ...

Страница 42: ...ront panel will direct the instrument to scan through the channels specified with MIN CHAN and MAX CHAN and store the number of readings specified by RDG CNT 7 Pressing EXIT will clear the current readings and reset the channel to channel 1 Remote interface Use the ROUTe SCAN LSELect command to select internal or external scanning For example to select internal scanning use the following command P...

Страница 43: ...hannels Open channels Open any closed channels Multiple channel commands Close specified channels 1 through 20 Query closed channels Open specified channels Scanning commands Program internal scan list Program external scan list Select scan list Sense subsystem Select measurement function Notes 1 The ROUT SCAN LSEL command is coupled to the ROUT SCAN INT command When the ROUT SCAN INT command is e...

Страница 44: ...y 2 pole switching is required for this application one Model 2000 SCAN 20 card can be used to switch up to 20 resistors Measurement accuracy can be optimized by minimizing residual resistance make connecting wires as short as possible and limit the number of connectors to minimize path resistance Another technique is to short one of the scanner channel inputs close the shorted channel and enable ...

Страница 45: ...minimizes the effects of voltage drops across the test leads greatly reducing measurement errors with lower DUT resistances Note however that an extra two poles of switching are required for each resistor tested For this reason only ten resistors can be tested using this configuration Figure 3 2 4 wire resistance test connections DMM 2000 20 Rear Panel 1 DUTs 10 R A Test Configuration B Simplified...

Страница 46: ...s for current measurements The current through each shunt resistor can be calculated as follows I V R Where I current being determined V voltage measured by multimeter R shunt resistance value Instead of manually calculating current set up a Model 2000 20 mX b math calculation function Here m 1 R and b 0 The multimeter will then display the actual current value Refer to the multimeter manual for d...

Страница 47: ...n resistance Path isolation resistance forms a signal path that is in parallel with the equivalent resistance of the DUT as shown in Figure 3 4 For low to medium device resistance values path isolation resistance is seldom a consideration however it can seriously degrade measurement accuracy when testing high impedance devices The voltage measured across such a device for example can be substantia...

Страница 48: ...ch as power transformers can generate substantial magnetic fields so care must be taken to keep the switching and measuring circuits a good distance away from these potential noise sources At high current levels even a single conductor can generate significant fields These effects can be minimized by using twisted pairs which will cancel out most of the resulting fields Electromagnetic interferenc...

Страница 49: ...s When two or more instruments are connected together care must be taken to avoid unwanted signals caused by ground loops Ground loops usually occur when sensitive instrumentation is connected to other instrumentation with more than one signal return path such as power line ground As shown inFigure 3 6 the resulting ground loop causes current to flow through the instrument LO signal leads and then...

Страница 50: ...omes contaminated the insu lation resistance will be substantially reduced affecting high impedance measurement paths Oils and salts from the skin can contaminate connector insulators reducing their resistance Also contaminants present in the air can be deposited on the insulator surface To avoid these problems never touch the connector insulating material In addition only use the scanner card in ...

Страница 51: ...3 16 Operation ...

Страница 52: ...4 Service Information Service Information ...

Страница 53: ... meets stated specifications Special handling of static sensitive devices Reviews precautions necessary when handling static sensitive devices Principles of operation Briefly discusses circuit operation Handling and cleaning precautions Because of the high impedance areas on the Model 2000 SCAN 20 take care when handling or servicing the card to prevent possible contamination The following precaut...

Страница 54: ...dry in a 50 C low humidity environment for several hours before use Performance verification The following paragraphs discuss performance verification procedures for the Model 2000 SCAN 20 including path resistance contact potential and isolation NOTE Contamination will degrade the performance of the card To avoid contamination always grasp the card by the side edges Do not touch connector insulat...

Страница 55: ...es 2 Connect the output cables to OUT A HI and LO as shown in Figure 4 1 3 With the power off install the scanner card in a Model 2000 20 Multimeter Table 4 1 Recommended verification equipment Description Model part Specifications Application Multimeter Electrometer with voltage source Sensitive Digital Voltmeter Triax cable unterminated Low thermal cable 22AWG solid copper wire 22AWG Teflon insu...

Страница 56: ...temporary leads from the multimeter and connect the output leads from the scanner card to the rear panel HI and LO INPUT jacks Figure 4 1 9 Program the multimeter to close channel 1 10 Note the resistance reading on the multimeter Verify that the reading is 2Ω 11 Repeat steps 9 and 10 for channels 2 through 20 Verify that the path resistance for each channel is 2Ω 12 After completing the tests tur...

Страница 57: ...d in the Model 2000 20 Multimeter 4 Turn on the multimeter and the voltmeter Allow the voltmeter to warm up for two hours before taking measurements 5 Select the 3mV range on the voltmeter 6 Select the DCV function on the multimeter 7 Program the multimeter to close channel 1 8 Verify that the voltmeter reading is 2µV 9 Repeat steps 7 and 8 for all 20 channels 10 After completing all measurements ...

Страница 58: ... it is on and remove the scanner card 2 Remove any jumpers or test leads connected to the card 3 Turn on the Model 6517A Electrometer and allow the unit to warm up for two hours before testing 4 Connect a 4 in length of Teflon insulated 22AWG stranded wire to every HI and LO input and output on the scanner card connectors J1035 and J1036 Mark the free end of each wire so you can identify the wires...

Страница 59: ...rometer voltage source off connect the electrometer to channel 1 HI and channel 2 HI as shown in Figure 4 4 Figure 4 4 Connections for channel to channel isolation tests 16 Turn on the Model 2000 20 Multimeter power 17 Program the multimeter to close channel 1 18 On the electrometer source 60V 19 After allowing the reading on the electrometer to settle verify that the reading is 100MΩ 108Ω This me...

Страница 60: ...lectrometer source 60V 28 After allowing the reading on the electrometer to settle verify that it is 100MΩ 108Ω 29 Turn off the electrometer voltage 30 Turn off the multimeter power 31 Repeat steps 24 through 30 for channels 2 through 20 One electrometer lead should be connected to the HI input of the channel being testing and the other lead should be con nected to chassis ground 32 Repeat steps 2...

Страница 61: ...y at a properly grounded workstation Also ground yourself with an appropriate wrist strap while working with these devices 3 Handle the devices only by the body do not touch the pins or terminals 4 Any printed circuit board into which the device is to be inserted must first be grounded to the bench or table 5 Use only anti static type de soldering tools and grounded tip soldering irons Principles ...

Страница 62: ...ppropriate relays are energized assuming the driver outputs are enabled as discussed below Note that a relay driver output goes low to energize the corresponding relay Switching circuits Relays K101 through K105 and K107 to K121 perform input switching while K106 configures the card for 2 pole or 4 pole operation Power on safeguard A power on safeguard circuit made up of U101 and associated compon...

Страница 63: ...4 12 Service Information ...

Страница 64: ...5 Replaceable Parts Replace ableParts ...

Страница 65: ...e inside front cover for addresses When ordering parts be sure to include the following information Card model number 2000 SCAN 20 Card serial number Part description Circuit description if applicable Keithley part number Factory service If the card is to be returned to Keithley Instruments for repair perform the following Call the Instruments Division Repair Department at 1 800 552 1115 for a Ret...

Страница 66: ...illips Pan Head Screw Card Ejector Crimp Housing Crimp Terminal Female Latching Block Sleeved Banana Plug Test Lead CAP 100µF 20 16V TANTALUM 7243 CAP 10µF 20 25V TANTALUM D7243 CAP 1µF 20 50V CERAMIC 1206 CONN RT ANGLE HEADER CONN RT ANGLE RELAY MINIATURE DPDT TQ2E L2 5V CONN FEMALE DUAL 16 PIN RES 4 75K 1 100MW THICK FILM 0805 RES 1K 1 100MW THICK FILM 0805 IC SUPPLY VOLT SUPERVISOR TL7705A SOIC...

Страница 67: ...5 4 Replaceable Parts ...

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Страница 74: ...A Specifications Section A Specs 7 8 03 4 32 PM Page 1 ...

Страница 75: ... Between Any Two Terminals 42 4VAC peak 60VDC Maximum Voltage Between Any Terminal and Model 2000 Input LO 42 4VAC peak 60VDC Internal Scanner Speed MAXIMUM INTERNAL SCANNER RATES RANGE Channels s1 TRIGGER DELAY 0 2WIRE 4WIRE DCV2 ACV2 3 OHMS2 OHMS2 TEMPERATURE2 All 100 All 90 All 95 10MΩ 31 All 60 TRIGGER DELAY AUTO 2WIRE 4WIRE DCV2 ACV2 3 OHMS2 OHMS2 TEMPERATURE2 0 1 V 95 All 1 8 100 Ω 81 100 Ω ...

Страница 76: ...tions 2 13 Current shunt locations 2 11 E Eliminating ground loops 3 15 F Factory service 5 2 Features 1 2 G General Information 1 1 H Handling and cleaning precautions 4 2 Handling precautions 4 2 Soldering precautions 4 3 Handling precautions 2 2 I Input and output connector terminal identification 2 6 Input connector J1036 pin designations 2 7 Introduction 1 2 2 2 3 2 4 2 5 2 M Manual addenda 1...

Страница 77: ...mitations 3 2 Special handling of static sensitive devices 4 10 Specifications 1 3 A 1 Summary of SCPI scanner commands 3 8 T Typical applications 3 9 Current measurements 3 11 Resistor testing 3 9 2 wire resistance tests 3 9 4 wire resistance tests 3 10 Typical connecting schemes 2 8 Current measurements 2 11 2 12 Board soldering and cleaning precautions 2 12 Current connections 2 13 Current shun...

Страница 78: ...Unstable Overload Will not read applied input Calibration only Certificate of calibration required Data required attach any additional sheets as necessary Show a block diagram of your measurement 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 _______________ __...

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Страница 81: ...1 60 11 77 26 GERMANY Landsberger Strasse 65 82110 Germering 089 84 93 07 40 Fax 089 84 93 07 34 GREAT BRITAIN Unit 2 Commerce Park Brunel Road Theale Berkshire RG7 4AB 0118 929 75 00 Fax 0118 929 75 19 INDIA 1 5 Eagles Street Langford Town Bangalore 560 025 080 212 80 27 Fax 080 212 80 05 ITALY Viale San Gimignano 38 20146 Milano 02 48 39 16 01 Fax 02 48 30 22 74 JAPAN New Pier Takeshiba North To...

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