Any unauthorized reproduction, photocopy, or use of the information herein, in whole or in part,
without the prior written approval of Keithley Instruments is strictly prohibited.
TSP®, TSP-Link®, and TSP-Net® are trademarks of Keithley Instruments. All Keithley Instruments
product names are trademarks or registered trademarks of Keithley Instruments. Other brand
names are trademarks or registered trademarks of their respective holders.
Document number: 2461-900-01 Rev. A / November 2015
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 nonhazardous 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 and follow all installation, operation, and maintenance information carefully before using
the product. Refer to the user documentation for complete product specifications.
If the product is used in a manner not specified, the protection provided by the product warranty may be impaired.
The types of product users are:
Responsible body is the individual or group responsible for the use and maintenance of equipment, for ensuring that the
equipment is operated within its specifications and operating limits, and for ensuring that operators are adequately trained.
Operators use the product for its intended function. They must be trained in electrical safety procedures and proper use of the
instrument. They must be protected from electric shock and contact with hazardous live circuits.
Maintenance personnel perform routine procedures on the product to keep it operating properly, for example, setting the line
voltage or replacing consumable materials. Maintenance procedures are described in the user documentation. The procedures
explicitly state if the operator may perform them. Otherwise, they should be performed only by service personnel.
Service personnel are trained to work on live circuits, perform safe installations, and repair products. Only properly trained
service personnel may perform installation and service procedures.
Keithley Instruments products are designed for use with electrical signals that are measurement, control, and data I/O
connections, with low transient overvoltages, and must not be directly connected to mains voltage or to voltage sources with high
transient overvoltages. Measurement Category II (as referenced in IEC 60664) connections require protection for high transient
overvoltages often associated with local AC mains connections. Certain Keithley measuring instruments may be connected to
mains. These instruments will be marked as category II or higher.
Unless explicitly allowed in the specifications, operating manual, and instrument labels, do not connect any instrument to mains.
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 than
30 V RMS, 42.4 V peak, or 60 VDC are present. A good safety practice is to expect that hazardous voltage is present in any
unknown circuit before measuring.
Operators of this product must be protected from electric shock at all times. The responsible body must ensure that operators
are prevented access and/or insulated from every connection point. In some cases, connections must be exposed to potential
human contact. Product operators in these circumstances must be trained to protect themselves from the risk of electric shock. If
the circuit is capable of operating at or above 1000 V, no conductive part of the circuit may be exposed.
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 mains. When connecting sources to switching cards, install protective
devices to limit fault current and voltage to the card.
Before operating an instrument, ensure that 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.
When installing equipment where access to the main power cord is restricted, such as rack mounting, a separate main input
power disconnect device must be provided in close proximity to the equipment and within easy reach of the operator.
For maximum safety, do not touch the product, test cables, or any other instruments while power is applied to the circuit under
test. ALWAYS remove power from the entire test system and discharge any capacitors before: 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.
For safety, instruments and accessories must be used in accordance with the operating instructions. If the instruments or
accessories are used in a manner not specified in the operating instructions, the protection provided by the equipment may be
impaired.
Do not exceed the maximum signal levels of the instruments and accessories, as defined in the specifications and operating
information, and as shown on the instrument or test fixture panels, or switching card.
When fuses are used in a product, replace with the same type and rating for continued protection against fire hazard.
Chassis connections must only be used as shield connections for measuring circuits, NOT as protective earth (safety ground)
connections.
If you are using a test fixture, keep 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, connect it to protective earth (safety ground) using the wire recommended in the user documentation.
The symbol on an instrument means caution, risk of danger. The user must refer to the operating instructions located in the
user documentation in all cases where the symbol is marked on the instrument.
The symbol on an instrument means caution, risk of electric shock. Use standard safety precautions to avoid personal
contact with these voltages.
The symbol on an instrument shows that the surface may be hot. Avoid personal contact to prevent burns.
The symbol indicates a connection terminal to the equipment frame.
If this symbol is on a product, it indicates that mercury is present in the display lamp. Please note that the lamp must be
properly disposed of according to federal, state, and local laws.
The WARNING heading in the user documentation 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 the user documentation explains hazards that could damage the instrument. Such damage may
invalidate the warranty.
Instrumentation and accessories shall not be connected to humans.
Before performing any maintenance, disconnect the line cord and all test cables.
To maintain protection from electric shock and fire, replacement components in mains circuits — including the power
transformer, test leads, and input jacks — must be purchased from Keithley Instruments. Standard fuses with applicable national
safety approvals may be used if the rating and type are the same. Other components that are not safety-related may be
purchased from other suppliers as long as they are equivalent to the original component (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.
To clean an instrument, use a damp cloth or mild, water-based cleaner. Clean the exterior of the instrument only. Do not apply
cleaner directly to the instrument or allow liquids to enter or spill on the instrument. Products that consist of a circuit board with
no case or chassis (e.g., a data acquisition board for installation into a computer) should never require cleaning if handled
according to instructions. If the board becomes contaminated and operation is affected, the board should be returned to the
factory for proper cleaning/servicing.
Thank you for choosing a Keithley Instruments product. The Model 2461 1 kW Pulse Mode Interactive
SourceMeter® Instrument is a precise, low-noise instrument that combines a stable DC power supply,
high-power, high-current source, electronic load, and high-impedance multimeter with pulse, contact
check, and digitize capabilities. This instrument features intuitive setup and control, enhanced signal
quality and range, and better resistivity and resistance capabilities than similar products on the
market.
The Model 2461 can source up to 7 A (10 A pulse), and features 1 A, 4 A, 5 A, 7 A, and 10 A ranges.
With 0.012 percent basic accuracy at 6½-digit resolution, the Model 2461 is a good solution for
testing a wide variety of materials and devices in applications such as power semiconductors, solar
energy, high brightness LEDs, power conversion, electrochemistry, batteries, and more.
Introduction to this manual
This manual provides detailed applications to help you achieve success with your Keithley
Instruments Model 2461. In addition, this manual provides information about the basics of the front
panel to familiarize you with the instrument.
This manual presents an overview of each application, followed by instructions to complete the
application using the front panel, SCPI code, TSP code, or Keithley KickStart Startup Software.
Extended warranty
More information about the commands that are used in these applications is available. Refer to the
SCPI and TSP command reference sections of the Model 2461 Reference Manual. This manual is on
the Product Information CD-ROM that came with your instrument.
Additional years of warranty coverage are available on many products. These valuable contracts
protect you from unbudgeted service expenses and provide additional years of protection at a fraction
of the price of a repair. Extended warranties are available on new and existing products. Contact your
local Keithley Instruments office, sales partner, or distributor for details.
Section 1: Introduction Model 2461 Interactive SourceMeter® Instrument User's Manual
1-2 2461-900-01 Rev. A / November 2015
Contact information
If you have any questions after you review the information in this documentation, please contact your
local Keithley Instruments office, sales partner, or distributor.
CD-ROM contents
The Model 2461 instrument Interactive SourceMeter® SMU Instruments Product Information CD-ROM
(Keithley Instruments part number 24GDI-950-01) is shipped with each Model 2461 instrument.
The Model 2461 Interactive SourceMeter SMU Instrument Product Information CD-ROM
contains:
operation information, and provides a quick test procedure to ensure the instrument is
operational.
User's Manual: Provides application examples that you can use as a starting point to create your
own applications.
Reference Manual: Includes advanced operation topics, maintenance information,
troubleshooting procedures, and in-depth descriptions of programming commands.
KickStart Startup Software Quick Start Guide: Provides instructions for the KickStart Startup
Software, which allows you to quickly make measurements and get results without having to
program test scripts.
Accessories information: Documentation for accessories that are available for the Model 2461.
Organization of manual sections
This manual is organized into the following sections:
Using the front-panel interface (on page 2-1): Describes the basics of using the front-panel
interface.
Using a remote interface (on page 3-1): Describes the basics of remote communications and
using the instrument web interface.
Application examples (see below): Provides detailed examples of how to use the Model 2461 in
some typical situations.
Model 2461 Interactive SourceMeter® Instrument User's Manual Section 1: Introduction
2461-900-01 Rev. A / November 2015 1-3
Troubleshooting FAQs (on page 11-1): Provides answers to frequently asked questions to help
you troubleshoot common problems encountered with the Model 2461.
Next steps (on page 12-1): Provides information about additional resources that can help you use
the Model 2461.
The PDF version of this manual contains bookmarks for each section. The manual sections are also
listed in the Table of Contents at the beginning of this manual.
For more information about bookmarks, see Adobe® Acrobat® or Reader® help.
Applications
This manual provides application examples that show you how to perform tests from the front panel
and over a remote interface. These applications are presented after the summary information about
the Model 2461. The applications include:
Making basic front-panel measurements (on page 4-1): Demonstrates the basic measurement
functionality using a single Model 2461 and a two-terminal device under test (DUT).
Measuring low-resistance devices (on page 5-1): Demonstrates how to use a Model 2461 to
make low-resistance measurements of a 20 m resistor.
Rechargeable battery measurements (on page 6-1): Demonstrates how to use a single Model
2461 to perform automated battery discharge and charge cycle testing.
Generating an I-V sweep on an LED with KickStart (on page 7-1): Demonstrates how use the
Model 2461 to test high-brightness light-emitting diodes (LEDs) using Keithley KickStart Startup
Software.
Measuring I-V characteristics of a solar panel (on page 8-1): Demonstrates using an I-V sweep to
characterize a solar panel using the Model 2461.
Making pulsed I-V measurements (on page 4-1): Demonstrates how to use the Model 2461
Interactive SourceMeter instrument to generate I-V curves of high-brightness LEDs (HBLEDs)
using the extended range pulsing capabilities of the instrument.
Capturing high-power pulse waveforms (on page 10-1): Demonstrates how to use the Model
2461 Interactive SourceMeter instrument to generate extended operating range, high-power
voltage pulses (up to 10 A at 100 V) and capture both the current and voltage waveforms of
high-power pulses.
In this section:
Front panel overview ................................................................ 2-1
Power the instrument on or off ................................................. 2-3
Turn the Model 2461 output on or off ....................................... 2-4
Store measurements on a USB flash drive ............................. 2-10
Saving screen captures to a USB flash drive ......................... 2-10
Section 2
Using the front-panel interface
Front panel overview
The front panel of the Model 2461 is shown below. Descriptions of the controls on the front panel
follow the figure.
Figure 1: Model 2461 front panel
Section 2: Using the front-panel interface Model 2461 Interactive SourceMeter® Instrument User's Manual
2-2 2461-900-01 Rev. A / November 2015
POWER switch
Turns the instrument on or off. To turn the instrument on, press the
power switch so that it is in the on position (|). To turn it off, press the
power switch so that it is in the off position (O).
HOME key
Returns the display to the Home screen.
MENU key
Opens the main menu. Press the icons on the main menu to open
source, measure, view, trigger, script, and system screens.
QUICKSET key
Opens a menu of preconfigured setups, including voltmeter,
ammeter, ohmmeter, and power supply. Also allows you to choose
source and measure functions and adjust performance for better
resolution or speed.
HELP key
Opens help for the area or item that is selected on the display. If
there is no selection when you press the HELP key, it displays
overview information for the screen you are viewing.
USB port
Saves reading buffer data and screen snapshots to a USB flash
drive. Also stores and retrieves scripts to and from a USB flash drive.
The flash drive must be formatted as a FAT drive.
Touchscreen
The Model 2461 has a high-resolution, five-inch color touchscreen
display. The touchscreen accesses swipe screens and menu options.
You can access additional interactive screens by pressing the
front-panel MENU, QUICKSET, and FUNCTION keys.
Navigation control
Turning the navigation control: Moves the cursor to highlight a list
value or menu item so that you can select it. Turning the control when
the cursor is in a value entry field increases or decreases the value in
the field.
Pressing the navigation control: Selects the highlighted choice or
allows you to edit the selected field.
ENTER key
Selects the highlighted choice or allows you to edit the selected field.
EXIT key
Returns to the previous screen or closes a dialog box. For example,
press the EXIT key when the main menu is displayed to return to the
Home screen. When you are viewing a subscreen (for example, the
Event Log screen), press the EXIT key to return to the main menu
screen.
FUNCTION key
Displays instrument functions. To select a function, touch the function
name on the screen.
TRIGGER key
Accesses trigger-related settings and operations. The action of the
TRIGGER key depends on the instrument state.
OUTPUT ON/OFF
switch
Turns the output source on or off. The key illuminates when the
source output is on.
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2461-900-01 Rev. A / November 2015 2-3
REMOTE LED
indicator
Illuminates when the instrument is controlled through a remote
interface.
LAN LED indicator
Illuminates when the instrument is connected to a local area network
(LAN).
1588 LED indicator
Illuminates when the instrument is connected to an IEEE-1588
INTERLOCK LED
indicator
Illuminates when the interlock is enabled.
SENSE terminals
Use the SENSE HI and SENSE LO terminal connections to measure
voltage at the device under test (DUT). When you use sense leads,
measurement of the voltage drop across the force leads is
eliminated. This produces more accurate voltage sourcing and
measurement at the DUT.
FORCE terminals
Use FORCE HI and FORCE LO terminal connections to source or
sink voltage or current to or from a device under test (DUT).
FRONT/REAR
TERMINALS switch
Activates the terminals on the front or rear panel. When the
front-panel terminals are active, a green "F" is visible to the left of the
FRONT/REAR switch. When the rear-panel terminals are active, a
yellow "R" is visible to the left of the switch.
Chassis connection
Banana jack connector that provides a chassis connection.
compliant device.
Note that 1588 functionality is not supported at this time. This
functionality will be made available with a firmware update.
Power the instrument on or off
Follow the steps below to connect the Model 2461 to line power and turn on the instrument. The
Model 2461 operates from a line voltage of 100 V to 240 V at a frequency of 50 Hz or 60 Hz. It
automatically senses line voltage and frequency. Make sure the operating voltage in your area is
compatible.
You must turn on the Model 2461 and allow it to warm up for at least one hour to achieve rated
accuracies.
Operating the instrument on an incorrect line voltage may cause damage to the instrument, possibly
voiding the warranty.
The power cord supplied with the Model 2461 contains a separate protective earth (safety
ground) wire for use with grounded outlets. When proper connections are made, the
instrument chassis is connected to power-line ground through the ground wire in the power
cord. In addition, a redundant protective earth connection is provided through a screw on
the rear panel. This terminal should be connected to a known protective earth. In the event
of a failure, not using a properly grounded protective earth and grounded outlet may result
in personal injury or death due to electric shock.
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Do not replace detachable mains supply cords with inadequately rated cords. Failure to use
properly rated cords may result in personal injury or death due to electric shock.
To connect the power cord:
1. Make sure that the front-panel POWER switch is in the off (O) position.
2. Connect the female end of the supplied power cord to the AC receptacle on the rear panel.
3. Connect the other end of the power cord to a grounded AC outlet.
Figure 2: Model 2461 rear panel
To turn a Model 2461 on or off:
1. Before turning the instrument on, disconnect any devices under test (DUTs) from the Model 2461.
2. To turn your instrument on, press the front-panel POWER switch to place it in the on (|) position.
The instrument displays a status bar as it powers on. The Home screen is displayed when power
on is complete.
3. To turn your instrument off, press the front-panel POWER switch to place it in the off (O) position.
Turn the Model 2461 output on or off
You can turn the Model 2461 output on from the front panel or by sending remote commands.
Turning the Model 2461 output off does not place the instrument in a safe state (an interlock
is provided for this function).
Hazardous voltages may be present on all output and guard terminals. To prevent electrical
shock that could cause injury or death, never make or break connections to the Model 2461
while the instrument is powered on. Turn off the equipment from the front panel or
disconnect the main power cord from the rear of the Model 2461 before handling cables.
Putting the equipment into an output-off state does not guarantee that the outputs are
powered off if a hardware or software fault occurs.
Model 2461 Interactive SourceMeter® Instrument User's Manual Section 2: Using the front-panel interface
2461-900-01 Rev. A / November 2015 2-5
When the source of the instrument is turned off, it may not completely isolate the instrument from the
external circuit. You can use the Output Off setting to place the Model 2461 in a known,
noninteractive state during idle periods, such as when you are changing the device under test. The
output-off states that can be selected for a Model 2461 are normal, high-impedance, zero, or guard.
See "Output-off state" in the Model 2461 Reference Manual for additional details.
Using the front panel:
Press the OUTPUT ON/OFF switch. The instrument is in the output-on state when the switch is
illuminated. The instrument is in the output-off state when the switch is not illuminated.
Using SCPI commands:
To turn the output on, send the command:
:OUTPut:STATe ON
To turn the output off, send the command:
:OUTPut:STATe OFF
Using TSP commands:
To turn the output on, send the command:
smu.source.output = smu.ON
To turn the output off, send the command:
smu.source.output = smu.OFF
Touchscreen display
The touchscreen display gives you quick front-panel access to source and measure settings, system
configuration, instrument and test status, reading buffer information, and other instrument
functionality. The display has multiple swipe screens that you can access by swiping the front panel.
You can access additional interactive screens by pressing the front-panel MENU, QUICKSET, and
FUNCTION keys.
Do not use sharp metal objects, such as tweezers or screwdrivers, or pointed objects, such as pens
or pencils, to touch the touchscreen. It is strongly recommended that you use only fingers to operate
the instrument. Use of clean-room gloves to operate the touchscreen is supported.
Select items on the touchscreen
To select an item on the displayed screen, do one of the following:
Touch it with your finger
Turn the navigation control to highlight the item, and then press the navigation control to select it
The following topics describe the Model 2461 touchscreen in more detail.
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2-6 2461-900-01 Rev. A / November 2015
Scroll bars
Some of the interactive screens have additional options that are only visible when you scroll down the
screen. A scroll indicator on the right side of the touchscreen identifies these screens. Swipe the
screen up or down to view the additional options.
The figure below shows a screen with a scroll bar.
Figure 3: Touchscreen window with a scroll bar indicator
Interactive swipe screens
The Model 2461 touchscreen display has multiple screens that you can access by gently swiping left
or right on the lower half of the display. The options available in the swipe screens are described in
the following topics.
Swipe screen heading bar
The heading bar of the swipe screen contains the following options.
Figure 4: Swipe screens, maximized and minimized
Model 2461 Interactive SourceMeter® Instrument User's Manual Section 2: Using the front-panel interface
2461-900-01 Rev. A / November 2015 2-7
#
Screen element
Description
1
Minimize indicator
You can swipe down to minimize the swipe screens.
2
Swipe screen indicator
Each circle represents one swipe screen. As you swipe right or left, a different
circle changes color, indicating where you are in the screen sequence. Select a
circle to go to a swipe screen without swiping.
3
Calculations shortcut
Select to open the CALCULATIONS SETTINGS menu.
4
Settings shortcut
Select to open the MEASURE SETTINGS menu for the selected function.
5
Restore indicator
Indicates that you can swipe up to display the swipe screen.
6
Graph shortcut
Select to open the Graph screen.
SOURCE swipe screen
The SOURCE swipe screen shows the present value of the source and the set values for source,
source range, and source limit. You can change the set values from the front panel by selecting the
buttons on this screen.
Figure 5: SOURCE swipe screen
Source function indicators on the right side of the screen signify settings that affect the displayed
source value.
MEAS: Source readback is on and the value shown is the measured value of the source.
PROG: Source readback is off and the value shown is the programmed source value. If the
output is off, the displayed source value is replaced with Output Off.
The icon on the right side of the swipe screen heading bar is a shortcut to the full SOURCE
SETTINGS menu.
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2-8 2461-900-01 Rev. A / November 2015
SETTINGS swipe screen
The SETTINGS swipe screen gives you front-panel access to some instrument settings. It shows you
the present settings and allows you to change, enable, or disable them quickly.
Figure 6: SETTINGS swipe screen
To disable or enable a setting, select the box next to the setting so that it shows an X (disabled) or a
check mark (enabled).
The icons on the right side of the swipe screen heading bar are shortcuts to the CALCULATIONS
SETTINGS and MEASURE SETTINGS menus.
For descriptions of the settings, use the navigation control to select the button, then press the HELP
key.
STATISTICS swipe screen
The STATISTICS swipe screen contains information about the readings in the active reading buffer.
When the reading buffer is configured to fill continuously and overwrite old data with new data, the
buffer statistics include the data that was overwritten. To get statistics that do not include data that
has been overwritten, define a large buffer size that will accommodate the number of readings you
will make. You can use the Clear Active Buffer button on this screen to clear the data from the
active reading buffer.
Figure 7: Model 2461 STATISTICS swipe screen
USER swipe screen
You can program custom text that appears on the USER swipe screen. For example, you can
program the Model 2461 to show that a test is in process. Refer to the Model 2461 Reference Manual, "Customizing a message for the USER swipe screen"
Figure 8: USER swipe screen
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2461-900-01 Rev. A / November 2015 2-9
GRAPH swipe screen
The GRAPH swipe screen shows a graphical representation of the readings in the presently selected
reading buffer.
Figure 9: GRAPH swipe screen
To view the graph in the full screen and to access graph settings, select the graph icon on the right
side of the swipe screen header. You can also open the full-function Graph screen by pressing the
MENU key and selecting Graph under Views.
For more information about graphing measurements, see "Graphing" in the Model 2461 Reference Manual.
Menu overview
To access the main menu, press the MENU key on the Model 2461 front panel. The figure below
shows the organization of the main menu.
Figure 10: Model 2461 main menu
The main menu includes submenus that are labeled in green across the top of the display. Touching
an icon in a submenu opens an interactive screen.
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2-10 2461-900-01 Rev. A / November 2015
Store measurements on a USB flash drive
If there is measurement data in the buffer, you can copy it from the Model 2461 to a USB flash drive.
The information is saved in the .csv file format.
To store measurement data:
1. Insert a flash drive into the front-panel USB port.
2. Press the MENU key.
3. In the Measure column, select Reading Buffers.
4. Select the buffer that you want to save.
5. Select Save to USB.
6. Enter a name for the new file.
7. Select the OK button on the displayed keyboard.
8. Select Yes to confirm saving the file.
9. Select OK to close the dialog box.
Saving screen captures to a USB flash drive
You can save the content of the front-panel display to a graphic file. The instrument saves these
graphic files, also known as screen captures, to the USB flash drive in the .png file format.
To save the screen capture:
1. Insert a USB flash drive in the USB port on the front panel of the instrument.
2. Navigate to the screen you want to capture.
3. Press the HOME and ENTER keys. The instrument displays "Saving screen capture."
LAN communications................................................................ 3-4
USB communications ............................................................... 3-6
Using the web interface .......................................................... 3-10
Determining the command set you will use ............................ 3-12
Section 3
Using a remote interface
Remote communications interfaces
You can choose from one of several communication interfaces to send commands to and receive
responses from the Model 2461.
You can control the Model 2461 from only one communications interface at a time. The first interface
on which it receives a message takes control of the instrument. If another interface sends a message,
that interface can take control of the instrument. You may need to enter a password to change the
interface, depending on the access mode.
The Model 2461 automatically detects the type of communications interface (LAN, GPIB, or USB)
when you connect to the respective port on the rear panel of the instrument. In most cases, you do
not need to configure anything on the instrument. In addition, you do not need to reboot if you change
the type of interface that is connected.
Supported remote interfaces
The Model 2461 supports the following remote interfaces:
GPIB: IEEE-488 instrumentation general purpose interface bus
Ethernet: Local area network ethernet communications
USB: Type B USB port
TSP-Link: A high-speed trigger synchronization and communications bus that test system
builders can use to connect multiple instruments in a master-and-subordinate configuration
For details about TSP-Link, see "TSP-Link System Expansion Interface" in the Model 2461 Reference Manual.
Section 3: Using a remote interface Model 2461 Interactive SourceMeter® Instrument User's Manual
3-2 2461-900-01 Rev. A / November 2015
GPIB communications
The Model 2461 GPIB interface is IEEE Std 488.1 compliant and supports IEEE Std 488.2 common
commands and status model topology.
You can have up to 15 devices connected to a GPIB interface, including the controller. The maximum
cable length is the lesser of either:
The number of devices multiplied by 2 m (6.5 ft)
20 m (65.6 ft)
Install the GPIB driver software
You may see erratic bus operation if you ignore these limits.
Check the documentation for your GPIB controller for information about where to acquire drivers.
Keithley Instruments also recommends that you check the website of the GPIB controller for the latest
version of drivers or software.
It is important that you install the drivers before you connect the hardware. This prevents associating
the incorrect driver to the hardware.
Install the GPIB cards in your computer
Refer to the documentation from the GPIB controller vendor for information about installing the GPIB
controllers.
Connect GPIB cables to your instrument
To connect an instrument to the GPIB interface, use a cable equipped with standard GPIB
connectors, as shown below.
Figure 11: GPIB connector
Model 2461 Interactive SourceMeter® Instrument User's Manual Section 3: Using a remote interface
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To allow many parallel connections to one instrument, stack the connectors. Each connector has two
screws to ensure that connections remain secure. The figure below shows a typical connection
diagram for a test system with multiple instruments.
To avoid possible mechanical damage, stack no more than three connectors on any one instrument.
To minimize interference caused by electromagnetic radiation, use only shielded GPIB cables.
Contact Keithley Instruments for shielded cables.
Figure 12: Model 2461 IEEE-488 connections
Set the GPIB address
The default GPIB address is 18. You can set the address to any address from 1 to 30 if it is unique in
the system. This address cannot conflict with an address that is assigned to another instrument or to
the GPIB controller.
GPIB controllers are usually set to 0 or 21. To be safe, do not configure any instrument to have an
address of 21. To change the controller address, see the documentation for the controller.
The instrument saves the address in nonvolatile memory. It does not change when you send a reset
command or when you turn the power off and then on again.
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To set the GPIB address from the front panel:
1. Press the MENU key.
2. Under System, select Communication. The SYSTEM COMMUNICATIONS window opens.
3. Select the GPIB tab.
4. Next to Address, select the number. The GPIB Address dialog box is displayed.
5. Enter the address.
6. Select OK.
LAN communications
You can communicate with the instrument using a local area network (LAN).
When you connect using a LAN, you can use a web browser to access the internal web page of the
instrument and change some of the instrument settings. For more information, see Using the web
interface (on page 3-10).
The Model 2461 is an LXI version 1.4 Core 2011 compliant instrument that supports TCP/IP and
complies with IEEE Std 802.3 (ethernet LAN). There is one LAN port (located on the rear panel of the
instrument) that supports full connectivity on a 10 Mbps or 100 Mbps network. The Model 2461
automatically detects the speed.
The Model 2461 also supports Multicast DNS (mDNS) and DNS Service Discovery (DNS-SD), which
are useful on a LAN with no central administration.
Contact your network administrator to confirm your specific network requirements before setting up a
LAN connection.
If you have problems setting up the LAN, refer to LAN troubleshooting suggestions (on page 3-10).
Set up LAN communications on the instrument
This section describes how to set up manual or automatic LAN communications on the instrument.
Set up automatic LAN configuration
If you are connecting to a LAN that has a DHCP server or if you have a direct connection between the
instrument and a host computer, you can use automatic IP address selection.
If you select Auto, the instrument attempts to get an IP address from a DHCP server. If this fails, it
reverts to an IP address in the range of 169.254.1.0 through 169.254.254.255.
Both the host computer and the instrument should be set to use automatic LAN configuration.
Though it is possible to have one set to manual configuration, it is more complicated to set up.
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To set up automatic IP address selection using the front panel:
1. Press the MENU key.
2. Under System, select Communication.
3. Select the LAN tab.
4. For TCP/IP Mode, select Auto.
5. Select Apply Settings to save your settings.
Set up manual LAN configuration
If necessary, you can set the IP address on the instrument manually.
You can also enable or disable the DNS settings and assign a host name to the DNS server.
Contact your corporate information technology (IT) department to secure a valid IP address for the
instrument when placing the instrument on a corporate network.
The instrument IP address has leading zeros, but the computer IP address cannot.
To set up manual IP address selection on the instrument:
1. Press the MENU key.
2. Under System, select Communication.
3. Select the LAN tab.
4. For TCP/IP Mode, select Manual.
5. For IP Address, enter the LAN IP address. You can touch the number you want to change.
6. For Gateway, enter the gateway address.
7. For Subnet, enter the subnet mask.
8. Select Apply Settings to save your settings.
Set up LAN communications on the computer
This section describes how to set up the LAN communications on your computer.
Do not change your IP address without consulting your system administrator. If you enter an
incorrect IP address, it can prevent your computer from connecting to your corporate network or it
may cause interference with another networked computer.
Record all network configurations before modifying any existing network configuration information on
the network interface card. Once the network configuration settings are updated, the previous
information is lost. This may cause a problem reconnecting the host computer to a corporate
network, particularly if DHCP is disabled.
Be sure to return all settings to their original configuration before reconnecting the host computer to a
corporate network. Contact your system administrator for more information.
Wait for the LAN status indicator on the front panel to turn solid green
A solid green LAN status indicator confirms that the instrument was assigned an IP address. Note
that it may take several minutes for the computer and instrument to establish a connection.
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Install LXI Discovery Browser software on your computer
You can use the LXI Discovery Browser to identify the IP addresses of LXI-certified instruments.
Once identified, you can double-click the IP address in the LXI Discovery Browser to open the web
interface for the instrument.
Run the LXI Discovery Browser
To run the LXI Discovery Browser software:
1. From the Microsoft Windows Start menu, select Keithley Instruments.
2. Select LXI Discovery Browser.
3. Click LXI Discovery Browser. The Keithley LXI Discovery Browser window is displayed.
The LXI Discovery Browser displays the instruments that it finds on the network and their
associated IP addresses.
4. Double-click an IP address in the LXI Discovery Browser dialog box. The instrument web page for
that instrument opens.
For information about using the web page, refer to Using the web interface (on page 3-10).
USB communications
To use the rear-panel USB port, you must have the Virtual Instrument Software Architecture (VISA)
layer on the host computer. See "How to install the Keithley I/O Layer" in the Model 2461 Reference Manual for more information.
VISA contains a USB-class driver for the USB Test and Measurement Class (USBTMC) protocol that,
once installed, allows the Microsoft® Windows® operating system to recognize the instrument.
When you connect a USB device that implements the USBTMC or USBTMC-USB488 protocol to the
computer, the VISA driver automatically detects the device. Note that the VISA driver only
automatically recognizes USBTMC and USBTMC-USB488 devices. It does not recognize other USB
devices, such as printers, scanners, and storage devices.
In this section, "USB instruments" refers to devices that implement the USBTMC or
USBTMC-USB488 protocol.
Connect a computer to the Model 2461 using USB
To connect the Model 2461 to a computer using a USB connection, use Keithley Instruments
Model USB-B-1, which is shipped with the instrument.
Each Model 2461 needs its own USB cable to be connected to the computer.
To connect an instrument to a computer using USB:
1. Connect the Type A end of the cable to the computer.
2. Connect the Type B end of the cable to the instrument.
3. Turn on the instrument power. When the computer detects the new USB connection, the Found
New Hardware Wizard starts.
4. If the "Can Windows connect to Windows Update to search for software?" dialog box opens, click
No, and then click Next.
5. On the "USB Test and Measurement device" dialog box, click Next, and then click Finish.
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Communicate with the instrument
For the instrument to communicate with the USB device, you must use NI-VISATM. VISA requires a
resource string in the following format to connect to the correct USB instrument:
USB0::0x05e6::0x2461::[serial number]::INSTR
Where:
0x05e6: The Keithley vendor ID
0x2461: The instrument model number
[serial number]: The serial number of the instrument (the serial number is also on the rear
panel)
INSTR: Use the USBTMC protocol
To determine these parameters, you can run the Keithley Configuration Panel, which automatically
detects all instruments connected to the computer.
If you installed the Keithley I/O Layer, you can access the Keithley Configuration Panel through the
Microsoft® Windows® Start menu.
To use the Keithley Configuration Panel to determine the VISA resource string:
1. Click Start > All Programs > Keithley Instruments > Keithley Configuration Panel. The
Select Operation dialog box is displayed.
Figure 13: Select Operation dialog box
2. Select Add.
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3. Click Next. The Select Communication Bus dialog box is displayed.
Figure 14: Select Communication Bus dialog box
4. Select USB.
5. Click Next. The Select Instrument Driver dialog box is displayed.
Figure 15: Select Instrument Driver dialog box
6. Select Auto-detect Instrument Driver - Model.
7. Click Next. The Configure USB Instrument dialog box is displayed with the detected instrument
VISA resource string visible.
8. Click Next. The Name Virtual Instrument dialog box is displayed.
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Figure 16: Name Virtual Instrument dialog box
9. In the Virtual Instrument Name box, enter a name that you want to use to refer to the instrument.
10. Click Finish.
11. Click Cancel to close the Wizard.
12. Save the configuration. From the Keithley Configuration Panel, select File > Save.
Verify the instrument through the Keithley Communicator: