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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 All Keithley product names are trademarks or registered trademarks of Keithley Instruments, Inc. Other brand names are trademarks or registered trademarks of their respective holders.
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Keithley products are designed for use with electrical signals that are rated Measurement Category I and Measurement Category II, as described in the International Electrotechnical Commission (IEC) Standard IEC 60664. Most measurement, control, and data I/O signals are Measurement Category I and must not be directly connected to mains voltage or to voltage sources with high transient over-voltages.
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(Note that selected parts should be purchased only through Keithley Instruments to maintain accuracy and functionality of the product.) If you are unsure about the applicability of a replacement component, call a Keithley Instruments office for information.
Table of Contents General Information Introduction ................Features ..................Manual addenda ................. Safety symbols and terms ............Specifications ................Unpacking and inspection ............Inspection for damage ............Handling precautions ............Shipment contents ............... Instruction manual .............. Repacking for shipment ............. Optional accessories ..............
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Operation Introduction ................Signal limitations ................ Relay input signal limitations ..........Scanner card detection ..............Power-up detection .............. Scanner option bus query ............ Model 2000-20 multimeter front panel scanner controls and SCPI scanner commands ............Closing channels ..............Opening channels ..............Selecting measurement function .........
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Replaceable Parts Introduction ................Parts list ..................Ordering information ..............Factory service ................Component layout and schematic diagram ........ Specifications...
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List of Illustrations Card Connections and Installation Figure 2-1 Model 2000-SCAN-20 simplified schematic ......Figure 2-2 Card connectors ..............Figure 2-3 Input and output connector terminal identification ....Figure 2-4 Connections for voltage scanning .......... Figure 2-5 Typical connections for 2-wire resistance scanning ....
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Input connector J1036 pin designations ......... Table 2-2 Output connector J1035 pin designations ......Operation Table 3-1 Summary of SCPI scanner commands ........Service Information Table 4-1 Recommended verification equipment ........Replaceable Parts Table 5-1 Model 2000-SCAN-20 parts list ..........
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General Information General Information...
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: •...
Unpacking and inspection Inspection for damage The Model 2000-SCAN-20 is packaged in a re-sealable, anti-static bag to protect it from damage due to static discharge and from contamination that could degrade its performance. Before removing the card from the bag, observe the following handling precautions.
Keithley part number 2000-20-901-00. The manual package includes an instruction manual and any pertinent addenda. Repacking for shipment Should it become necessary to return the Model 2000-SCAN-20 for repair, carefully pack the unit in its original packing carton, or the equivalent, and include the following information: •...
General Information Optional accessories The following accessories are available for use with the Model 2000-SCAN-20 scanner card: • Models 2000-MTC-2 and 2000-MTC-4 Cable Assemblies — This 2m or 4m cable assembly is terminated with a DB44 female connector on one end and is unterminated at the other end.
Failure to recognize and observe normal safety precautions could result in personal injury or death. This section includes information on making connections to the Model 2000-SCAN-20 and installing the card in a Model 2000-20 Multimeter. This section is arranged as follows: •...
All connections must be connected to the card before it is installed in a multimeter. Connection precautions WARNING Connection information for the Model 2000-SCAN-20 is intended for qualified service personnel. Do not attempt to connect the DUT or external circuitry to a scanner card unless qualified to do so.
Card configuration Figure 2-1 shows a simplified schematic diagram of the Model 2000-SCAN-20. The scanner card has 20 input channels and two outputs. Channels 1 through 20 are all switched by relays. In 2-pole mode, the OUT A HI and LO connections are for all 20 channels. In 4-pole mode, the OUT A HI and LO connections are for channels 1 through 10 and the OUT B HI and LO connections are for channels 11 through 20.
Card Connections and Installation Card connectors Figure 2-2 shows the input and output connectors for the card. Card connector J1036 provides the HI and LO input connections for all 20 channels, and J1035 provides the HI and LO outputs. Terminal identification for connectors J1035 and J1036 is provided in Figure 2-3 Table 2-1 Table...
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Card Connections and Installation Figure 2-3 Input and output connector terminal identification 26 HI Channel 1 11 LO 29 HI Channel 2 14 LO J1036 33 HI Channel 3 34 LO 23 HI Channel 4 J1035 39 HI Channel 5 40 LO 43 HI Channel 6...
• • Frequency (voltage only) All channels (1 through 20) can be used with this configuration. Figure 2-4 Connections for voltage scanning J1036 CH 1 Voltages Under Test CH 20 J1035 To DMM OUT A Input OUT B 2000-SCAN-20 Card...
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 J1036 CH 1 Resistors Under Test CH 20 J1035 To DMM OUT A Input OUT B 2000-SCAN-20 Card...
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4-wire resistance measurements. Figure 2-6 Typical connections for 4-wire resistance scanning J1036 CH 1 CH 2 Resistors Under Test CH 10 CH 11 CH 12 CH 20 J1035 To DMM Input OUT A To DMM Sense OUT B 2000-SCAN-20 Card...
Card Connections and Installation 2-11 Current measurements Current shunts can be installed on the circuit board to measure indirect AC and DC currents through channels 1 and 11 only. The following paragraphs discuss installing current shunts and the basic methods used to determine currents. CAUTION Board-mounted current shunt resistors can be installed only for channels 1 and 11.
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2-12 Card Connections and Installation Board soldering and cleaning precautions NOTE Failure to observe the following precautions may result in degraded card performance. When soldering resistors, only touch areas associated with resistor installation and do not spread flux to other areas of the circuit board. Use solder with an OA (organic activated) flux. Thoroughly clean the circuit board with pure water after soldering to remove all contaminants.
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Current connections Figure 2-8 shows typical connections for measuring currents using the Model 2000-SCAN-20 with current shunts installed. As noted previously, only channels 1 and 11 have current shunts installed. This configuration can be used to scan the following: •...
2-14 Card Connections and Installation Card installation and removal This paragraph explains how to install and remove the Model 2000-SCAN-20 card assembly from the Model 2000-20 Multimeter. WARNING Installation or removal of the Model 2000-SCAN-20 should be performed only by qualified service personnel. Failure to recognize and observe standard safety precautions could result in personal injury or death.
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Card Connections and Installation 2-15 Figure 2-9 Card installation Unlock Card Ejector Arms (2) NOTE: Card connections are removed for clarity. Lock Card...
2-16 Card Connections and Installation Output connections to multimeter After installation, connect the scanner card output leads to the multimeter rear panel jacks as follows: WARNING Signals applied to the front inputs of the multimeter cannot exceed the ratings of the scanner card as long as the scanner card output leads are connected to the multimeter rear panel input jacks.
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.
Introduction This section contains detailed information on front panel and IEEE-488 bus operation of the Model 2000-SCAN-20. The information in this section is organized as follows: • Signal limitations — Summarizes the maximum signals that can be applied to the Model 2000-SCAN-20.
*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 this query is as follows: •...
SCPI scanner commands The following paragraphs give an overview of the various Model 2000-20 Multimeter front panel controls and corresponding IEEE-488 SCPI bus commands used with the Model 2000-SCAN-20. Closing channels Front panel Use the front panel CLOSE key to close specific channels as follows: From the normal display, press the CLOSE key.
Operation Opening channels Front panel Use the front panel OPEN key to open all the card channels. Remote interface Use the :ROUTe:OPEN:ALL command to open all the channels. The command is as follows: PRINT #1, "output 16; :route:open:all" Use the :ROUTe:MULTiple:OPEN command to open specified channels. For example, if you want to open channels 1, 3, and 5, use the following command: PRINT #1, "output 16;...
Operation Configuring scan parameters This paragraph details how to select internal scanning and how to configure the scan parameters. Front Panel Use the SHIFT-CONFIG keys to select the scan type and configure the scan parameters. Press SHIFT and then CONFIG. The instrument will display the following prompt for internal scanning: TYPE: I20 Use the L or M key if EXT is displayed and press ENTER.
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Operation The following options start the scanning process: STEP — Pressing the STEP key on the front panel will direct the instrument to begin scanning at channel 1 and scan the number of channels specified with RDG CNT. It will store the same number of readings.
Operation SCPI scanner commands Table 3-1 summarizes commands that control scanner operations over the remote interface. For more detailed information on these and other bus commands, refer to the multimeter manual. Table 3-1 Summary of SCPI scanner commands Command Description :ROUTe Route subsystem.
Operation Typical applications Resistor testing The Model 2000-SCAN-20 can be used to test up to 20 resistors using 2-wire measurements or up to ten resistors using 4-wire measurements. Such tests use the Model 2000-20 Ω2 and Ω4 resistance functions. 2-wire resistance tests Figure 3-1 shows a typical test setup for making 2-wire resistance measurements.
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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 2000-SCAN-20 Out A DUTs (10) DMM 2000-20...
Operation 3-11 Current measurements Although the Model 2000-SCAN-20 is not intended for direct current measurements, on-card shunt resistors can be installed for channels 1 and 11 to allow for indirect current measurements. Figure 3-3 shows the typical configuration for current measurements. Refer to...
3-12 Operation Measurement considerations Many measurements made with the Model 2000-SCAN-20 are subject to various effects that can seriously affect low-level measurement accuracy. The following paragraphs discuss these effects and ways to minimize them. Path isolation Path isolation is simply the equivalent impedance between any two test paths in a measurement system.
Operation 3-13 Figure 3-5 Voltage attenuation by path isolation resistance PATH PATH PATH Magnetic fields When a conductor cuts through magnetic lines of force, a very small current is generated. This phenomenon will frequently cause unwanted signals to occur in the test leads of a scanning system.
3-14 Operation The instrument, measurement leads, and other cables should be kept as far away as possible from any EMI sources. Shielding measurement leads and the multimeter may reduce EMI to acceptable levels. In extreme cases, a specially constructed screen room may be required to sufficiently attenuate troublesome signals.
Operation 3-15 Figure 3-7 shows how to connect several instruments together to eliminate this type of ground loop problem. Here, only one instrument is connected to power line ground. Ground loops are not normally a problem with instruments having isolated LO terminals. However, all instruments in the test setup may not be designed in this manner.
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 precautions should be observed when servicing the card.
Service Information Soldering precautions Should it become necessary to use solder on the circuit board, observe the following precautions: • Use an OA-based (organic activated) flux and take care not to spread the flux to other areas of the circuit board. •...
Table 4-1 Recommended verification equipment Description Model/part Specifications Application Multimeter Keithley 2000-20 100Ω; 100ppm of Control card, measure path resistance reading; 40ppm of range Electrometer with voltage Keithley 6517A 20pA, 200pA; 1.0% Path isolation source 100V source;...
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Figure 4-1 Connections for path resistance checks Jumper HI and LO of all 20 Channels Input Channel 1 DMM 2000-20 Channel 2-9 Rear Panel OUT A Channel 10 Input OUT B 4-Pole 2-Pole Channel 11 Channel 12-19 Channel 20 Model 2000-SCAN-20...
TALK LSTN Model 1484 Connect bare copper jumpers between Low-Thermal Cable HI and LO of each channel (Unterminated) Model 182 Channel 1 Channel 2-9 OUT A Channel 10 OUT B 4-Pole 2-Pole Channel 11 Channel 12-19 Channel 20 Model 2000-SCAN-20...
V-Source LO (Ground Link Cable Removed) V-Source HI Channel 1 Channel 2-9 LO OUT A Channel 10 Model 6171 Triax Adapter Model 6517A OUT B (Red) 4-Pole 2-Pole Model 7025 Unterminated Channel 11 Triax Cable Channel 12-19 Channel 20 Model 2000-SCAN-20...
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With the Model 6517A Electrometer 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 Source V and Model 2000-SCAN-20 Measure V/I Banana to Banana (Ground Link V-Source LO Cable...
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1 HI and chassis ground as shown in Figure 4-5. Figure 4-5 Connections for HI and LO input-to-chassis ground isolation tests Model 7025 Unterminated Triax Cable Model 2000-SCAN-20 (Red) Source V and Channel 1 Measure V/I Banana to Channel 2-9 Banana...
The following paragraphs discuss the basic operating principles for the Model 2000-SCAN-20 and can be used as an aid in troubleshooting the card. The schematic drawing of the card is shown on drawing number 2000-186 located at the end of...
Service Information 4-11 Figure 4-6 Block diagram Clock Relay Relays User Connections Data Drivers Multimeter Strobe K101-K121 U102-U107 Enable Power-on Reset U101 Relay control Card relays are controlled by serial data transmitted via the relay DATA line. A total of six bytes are shifted in serial fashion into latches located in the card relay driver ICs.
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 Return Material Authorization (RMA) number.
Replaceable Parts Component layout and schematic diagram A component layout drawing and schematic diagram are included on the following pages integrated with the parts list (Table 5-1) for the Model 2000-SCAN-20. Table 5-1 Model 2000-SCAN-20 parts list Keithley part Circuit desig.
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Specs and Accessories GENERAL: Scanner Configuration 20 Channels: 20 channels of 2-pole relay input. All channels configurable to 4-pole. Relay Type: Latching electromechanical. Channel 1 Actuation Time: <3.5ms. Safety: Conforms with European Union Directive 73/23/EEC. Channel 2–9 EMC: Conforms with European Union Directive 89/336/EEC. CAPABILITIES: Multiplex one of twenty 2-pole or one of ten Channel 10 OUT A...
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Opening channels Connections for path resistance checks Front panel Connections for same-channel isolation Remote interface tests Selecting measurement function Connections for voltage scanning Model 2000-SCAN-20 parts list Current connections 2-13 Model 2000-SCAN-20 simplified Current shunt locations 2-11 schematic Eliminating ground loops...
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Parts list Typical applications Path isolation resistance 3-12 Current measurements 3-11 Performance verification Resistor testing Contact potential tests 2-wire resistance tests Environmental conditions 4-wire resistance tests 3-10 Isolation tests Typical connecting schemes Path resistance tests Current measurements 2-11, 2-12 Recommended equipment Board soldering and cleaning precautions 2-12...
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Service Form Model No. ____________ Serial No. _______________ Date _________________ Name and Telephone No. _____________________________________________ Company _________________________________________________________________ List all control settings, describe problem and check boxes that apply to problem. _________________________ __________________________________________________________________________________________ __________________________________________________________________________________________ ❑ Intermittent ❑ Analog output follows display ❑...
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Specifications are subject to change without notice. All Keithley trademarks and trade names are the property of Keithley Instruments, Inc. All other trademarks and trade names are the property of their respective companies. Keithley Instruments, Inc. 28775 Aurora Road • Cleveland, Ohio 44139 • 440-248-0400 • Fax: 440-248-6168 1-888-KEITHLEY (534-8453) •...
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