Keithley 6487 User manual

www.keithley.com
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Reference Manual
6487-901-01 Rev. B / March 2011
Model 6487 Picoammeter/Voltage Source
Model 6487 Picoammeter/Voltage Source

Model 6487
Picoammeter/Voltage Source
Reference Manual
© 2002-2011, Keithley Instruments, Inc.
Cleveland, Ohio, U.S.A.
All rights reserved.
Any unauthorized reproduction, photocopy, or use the information herein, in whole or in part,
without the prior written approval of Keithley Instruments, Inc. is strictly prohibited.
All Keithley Instruments product names are trademarks or registered trademarks of Keithley
Instruments, Inc. Other brand names are trademarks or registered trademarks of their respective
holders.
The Lua 5.0 software and associated documentation files are copyright © 1994-2008, Tecgraf,
PUC-Rio. Terms of license for the Lua software and associated documentation can be accessed at
the Lua licensing site (http://www.lua.org/license.html).
Keithley's standard terms and conditions of sale in effect at the time of acceptance of buyer's order
by Keithley shall apply to all purchase of goods and performance of services from Keithley, to the
exclusion of any additional or different terms and conditions, including any terms or conditions
which buyer may purport to apply under any buyer's request for quotation, purchase order or similar
document, or which buyer may offer in response to these terms. A copy of Keithley's current terms
can be accessed at http://www.keithley.com/company/termsandconditions (these "Terms"). To
obtain a printed copy of these Terms, please contact your local sales office or send an email to
[email protected]. Buyer's assent to these Terms, and only these Terms, shall be conclusively
presumed from buyer's acceptance of delivery of the products and/or services provided by Keithley.
Document number: 6487-901-01 Rev. B / March 2011

Safety Precautions
04/09
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 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 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. 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 user documentation.
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 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.
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 volts, 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. Whenconnecting sources to switching cards,
install protective devices to limit fault current and voltage to the card.
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.
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.
The instrument and accessories must be used in accordance with specifications and operating instructions, or the
safety of 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 safety earth 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 safety earth ground using the wire recommended in the user documentation.
The symbol on an instrument means caution, risk of danger. The user should 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 danger. User 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., 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.
!

Table of Contents
1 Getting Started
Introduction ................................................................................ 1-2
Overview of this manual ............................................................ 1-2
General information ................................................................... 1-3
Warranty information .......................................................... 1-3
Contact information ............................................................ 1-3
Safety symbols and terms ................................................... 1-3
Unpacking and Inspection .................................................. 1-3
Reference manual ............................................................... 1-4
Additional references .......................................................... 1-4
Power-up .................................................................................... 1-5
Line power connection ........................................................ 1-5
Line frequency .................................................................... 1-6
Power-up sequence ............................................................. 1-7
Front panel operation ................................................................. 1-8
Status and error messages .......................................................... 1-8
Default settings .......................................................................... 1-8
Front panel setup operation ................................................. 1-9
Remote setup operation ...................................................... 1-9
Menus ....................................................................................... 1-12
Main menus ....................................................................... 1-12
Configuration menus ......................................................... 1-13
SCPI programming .................................................................. 1-14
Optional command words ................................................. 1-14
Query commands .............................................................. 1-14
2 Measurement Concepts
and Connections
Connection fundamentals ........................................................... 2-2
Input connector ................................................................... 2-2
Voltage source output connectors ....................................... 2-2
Maximum input levels ........................................................ 2-3
Low-noise input cables ....................................................... 2-3
Voltage source test leads ..................................................... 2-4
Basic connections to DUT ......................................................... 2-4
Current measurement connections ...................................... 2-4
Ohms measurement connections ........................................ 2-5
Voltage source connections ................................................. 2-6
Voltages greater than 505V ................................................. 2-6
Noise and safety shields ...................................................... 2-8
Using a test fixture ..................................................................... 2-8

General purpose test fixture ................................................ 2-9
Model 8009 resistivity test fixture ..................................... 2-11
Floating measurements ...................................................... 2-12
Interlock .................................................................................... 2-13
Interlock connections ........................................................ 2-13
Interlock operation ............................................................ 2-14
Interlock programming ...................................................... 2-14
Analog output ........................................................................... 2-14
Measurement considerations .................................................... 2-16
3 Measurements and
Sourcing Voltage
Measurement overview ............................................................... 3-2
Current measurements ......................................................... 3-2
Voltage source ..................................................................... 3-2
Performance considerations ........................................................ 3-3
Warm-up period ................................................................... 3-3
Voltage offset correction ..................................................... 3-3
Autozero .............................................................................. 3-3
Zero check and zero correct ................................................ 3-4
Current measurements ................................................................ 3-7
Procedure ............................................................................. 3-7
Programming example ...................................................... 3-11
Ohms measurements ................................................................. 3-11
Overview ........................................................................... 3-11
Procedure ........................................................................... 3-12
SCPI programming — ohms measurements ..................... 3-14
Programming example — ohms measurements ................ 3-15
Voltage source operation .......................................................... 3-15
Voltage source edit keys .................................................... 3-15
Configuring the voltage source ......................................... 3-15
Sourcing voltage ................................................................ 3-16
Operate considerations ...................................................... 3-18
Compliance indication ....................................................... 3-18
Open interlock indication .................................................. 3-18
SCPI commands — voltage source ................................... 3-19
Programming example — voltage ..................................... 3-20
Alternating voltage ohms mode ................................................ 3-21
Overview ........................................................................... 3-21
Storing A-V ohms readings ............................................... 3-23
Recalling A-V ohms readings ........................................... 3-24
Operating considerations ................................................... 3-25
SCPI commands — A-V ohms ......................................... 3-28
Programming example — A-V ohms measurements ........ 3-31

4 Range, Units, Digits,
Rate, and Filters
Range, units, and digits .............................................................. 4-2
Range .................................................................................. 4-2
Units .................................................................................... 4-3
Digits ................................................................................... 4-4
SCPI programming — range and digits .............................. 4-4
Rate ............................................................................................ 4-6
SCPI programming — rate ................................................. 4-7
Damping ..................................................................................... 4-8
Filters ......................................................................................... 4-8
Median filter ........................................................................ 4-9
Median filter control ........................................................... 4-9
Digital filter ....................................................................... 4-10
SCPI programming — filters ............................................ 4-12
5 Relative, mX+b, m/X+b, and log
Relative ...................................................................................... 5-2
Setting and controlling relative ........................................... 5-2
SCPI programming — relative .......................................... 5-4
mX+b, m/X+b (reciprocal), and logarithmic ............................. 5-5
mX+b and m/X+b ............................................................... 5-5
Configuring and controlling mX+b and m/X+b ................. 5-5
Logarithmic ......................................................................... 5-6
SCPI programming — mX+b, m/X+b, and log .................. 5-7
6 Buffer and Sweeps
Buffer operations ........................................................................ 6-2
Store .................................................................................... 6-2
Recall .................................................................................. 6-2
Buffer timestamps ............................................................... 6-3
Buffer statistics ................................................................... 6-4
SCPI programming ............................................................. 6-4
Programming example ........................................................ 6-8
Voltage sweeps ........................................................................... 6-8
Overview ............................................................................. 6-8
Sweep operation ................................................................ 6-10
Recalling sweep data ........................................................ 6-10
Operating considerations .................................................. 6-10
Sweep example ................................................................. 6-11
SCPI programming — sweeps .......................................... 6-12
Programming example ...................................................... 6-15

7 Triggering
Trigger models ............................................................................ 7-2
Idle and initiate .................................................................... 7-4
Trigger model operation ...................................................... 7-5
Trigger model configuration — front panel ........................ 7-8
SCPI programming ................................................................... 7-10
Programming example ...................................................... 7-11
External triggering .................................................................... 7-12
Input trigger requirements ................................................. 7-12
Output trigger specifications ............................................. 7-13
External trigger example ................................................... 7-13
8 Limit Tests and Digital I/O
Limit testing ................................................................................ 8-2
Binning ....................................................................................... 8-5
Component handler interface .............................................. 8-7
Component handler types .................................................... 8-8
Digital output clear pattern ................................................ 8-10
Digital I/O port ......................................................................... 8-11
Sink mode — controlling external devices ....................... 8-12
Source mode — logic control ............................................ 8-14
Setting digital output lines ................................................. 8-14
SCPI programming — digital output pattern .................... 8-15
Front panel operation — limit tests .......................................... 8-16
Limit test configuration ..................................................... 8-16
Performing limit tests ........................................................ 8-17
SCPI programming — limit tests ............................................. 8-18
Programming example ...................................................... 8-21
9 Remote Operation
Selecting and configuring an interface ....................................... 9-2
Interfaces ............................................................................. 9-2
Languages ............................................................................ 9-2
Interface selection and configuration procedures ................ 9-3
GPIB operation and reference .................................................... 9-4
GPIB bus standards ............................................................. 9-4
GPIB bus connections ......................................................... 9-4
Primary address ................................................................... 9-6
General IEEE-488 bus commands ...................................... 9-7
Front panel GPIB operation ................................................ 9-9
Programming syntax ......................................................... 9-10
RS-232 interface reference ....................................................... 9-16
Sending and receiving data ................................................ 9-16

RS-232 settings ................................................................. 9-16
RS-232 connections .......................................................... 9-18
Error messages .................................................................. 9-19
10 Status Structure
Overview .................................................................................. 10-2
Clearing registers and queues ................................................... 10-4
Programming and reading registers ......................................... 10-5
Programming enable registers ........................................... 10-5
Reading registers ............................................................... 10-6
Status byte and service request (SRQ) ..................................... 10-7
Status byte register ............................................................ 10-7
Service request enable register .......................................... 10-8
Serial polling and SRQ ..................................................... 10-9
Status byte and service request commands ....................... 10-9
Status register sets .................................................................. 10-10
Register bit descriptions .................................................. 10-10
Queues .................................................................................... 10-17
Output queue ................................................................... 10-18
Error queue ..................................................................... 10-19
11 Common Commands
Common commands ................................................................ 11-2
12 SCPI Signal Oriented Measurement Commands
13 DISPlay, FORMat, and SYSTem
DISPlay subsystem .................................................................. 13-2
FORMat subsystem .................................................................. 13-4
SYSTem subsystem .................................................................. 13-9
14 SCPI Reference Tables
General notes ............................................................................ 14-2
15 Performance Verification
Introduction .............................................................................. 15-2
Verification test requirements .................................................. 15-2
Environmental conditions ................................................. 15-2
Warm-up period ................................................................ 15-3
Line power ........................................................................ 15-3
Recommended test equipment ................................................. 15-3
Verification limits ..................................................................... 15-5

Example reading limits calculation ................................... 15-5
Calibrator voltage calculations ................................................. 15-5
Performing the verification test procedures .............................. 15-6
Test considerations ............................................................ 15-6
Restoring factory defaults ................................................. 15-6
Offset voltage calibration ......................................................... 15-7
Current measurement accuracy ................................................ 15-7
20µA-20mA range accuracy .............................................. 15-7
2nA-2µA range accuracy ................................................... 15-8
Voltage source output accuracy .............................................. 15-10
16 Calibration
Introduction .............................................................................. 16-2
Environmental conditions ......................................................... 16-2
Temperature and relative humidity .................................... 16-2
Warm-up period ................................................................. 16-2
Line power ......................................................................... 16-2
Calibration considerations ........................................................ 16-3
Calibration cycle ....................................................................... 16-3
Recommended calibration equipment ...................................... 16-3
Calibration errors ...................................................................... 16-4
Calibration menu ...................................................................... 16-5
Aborting calibration .................................................................. 16-6
Current calculations .................................................................. 16-6
Calibration procedure ............................................................... 16-7
Preparing for calibration .................................................... 16-7
Offset voltage calibration .................................................. 16-7
Current calibration ............................................................. 16-8
Voltage source calibration ............................................... 16-12
Entering calibration dates and saving calibration ............ 16-13
Locking out calibration ................................................... 16-14
Calibration support ................................................................. 16-14
Changing the calibration code ......................................... 16-14
Resetting the calibration code ......................................... 16-15
Displaying calibration dates ............................................ 16-15
Displaying the calibration count ..................................... 16-15
17 Routine Maintenance
Introduction .............................................................................. 17-2
Setting line voltage and replacing line fuse .............................. 17-2
Front panel tests ........................................................................ 17-3
DISP test ............................................................................ 17-4
KEY test ............................................................................ 17-4

A Specifications
B Status and Error Messages
Eliminating common SCPI errors ............................................. B-7
-113, "Undefined header" .................................................. B-7
-410, "Query INTERRUPTED" ......................................... B-7
- 420, "Query UNTERMINATED" .................................... B-8
C DDC Emulation Commands
DDC language ........................................................................... C-2
Sweeps or A-V ohms in DDC mode ................................ C-10
Status words ..................................................................... C-11
Status byte format ............................................................ C-12
D IEEE-488 Bus Overview
Introduction ............................................................................... D-2
Bus description .......................................................................... D-3
Bus lines .................................................................................... D-4
Data lines ........................................................................... D-5
Bus management lines ....................................................... D-5
Handshake lines ................................................................. D-5
Bus commands .......................................................................... D-6
Uniline commands ............................................................. D-9
Universal multiline commands .......................................... D-9
Addressed multiline commands ....................................... D-10
Address commands .......................................................... D-10
Unaddress commands ...................................................... D-10
Common commands ........................................................ D-11
SCPI commands ............................................................... D-11
Command codes ............................................................... D-11
Typical command sequences ............................................ D-12
IEEE command groups .................................................... D-13
Interface function codes .......................................................... D-14
E IEEE-488 and SCPI
Conformance Information
Introduction ................................................................................ E-2
GPIB 488.1 Protocol .................................................................. E-3
Selecting the 488.1 protocol ....................................................... E-4
Protocol differences ................................................................... E-5
Message exchange protocol (MEP) .................................... E-5
Using SCPI-based programs ............................................... E-5
NRFD hold-off .................................................................... E-6

NDAC hold-off ................................................................... E-6
Trigger-on-talk ................................................................... E-7
Message available ............................................................... E-7
General operation notes ...................................................... E-7
SRQ when buffer fills with 200 readings ........................... E-8
F Remote Calibration
Introduction ............................................................................... F-2
Calibration commands ............................................................... F-2
Remote calibration overview ..................................................... F-3
G Applications Guide
Measurement considerations ..................................................... G-2
Leakage currents and guarding .......................................... G-2
Input bias current ................................................................ G-3
Voltage burden .................................................................... G-4
Noise and source impedance .............................................. G-5
Electrostatic interference and shielding ............................. G-7
Making connections ......................................................... G-10
Typical range change transients ....................................... G-12
Steps to minimize impact of range change transients ...... G-16
Zero check on / off response ............................................ G-17
Applications ............................................................................. G-18
Diode leakage current ....................................................... G-18
Capacitor leakage current ................................................. G-19
Measuring high resistance ................................................ G-19
Alternating voltage ohms measurement ........................... G-20
Cable insulation resistance ............................................... G-21
Surface insulation resistance (SIR) .................................. G-22
Photodiode characterization prior to dicing ..................... G-23
Focused ion beam applications ........................................ G-25
Using switching systems to measure multiple current sources G-26

1
Getting Started
•Introduction — Description of the Model 6487 Picoammeter.
•Overview of this manual — Provides content of this manual.
•General information — Covers general information that includes warranty infor-
mation, contact information, safety symbols and terms, and inspection.
•Power-up — Covers line power connection, line voltage setting, fuse replacement,
power line frequency, and the power-up sequence.
•Front panel operation — Shows the location of front panel controls, displays, and
indicators.
•Status and error messages — Status and error messages.
•Default settings — Covers the five instrument setup configurations available to the
user: three user defined, GPIB defaults, or factory defaults.
•Menus — Listing of the main and configuration menu items.
•SCPI programming — Explains how SCPI commands are presented in this
manual.

1-2 Getting Started Model 6487 Reference Manual
Introduction
The Model 6487 is a high resolution bus-programmable (RS-232 and IEEE-488)
picoammeter. The Model 6487 has the following current measurement ranges: 8 ranges,
from 20mA down to the 2nA range. The Model 6487 also has a built-in ±500V DC voltage
source and an ohms function that includes an alternating voltage mode for enhanced high
resistance measurement accuracy.
Overview of this manual
This manual describes how to connect, program, and maintain the Model 6487
Picoammeter. The sections of the manual are organized as follows:
–Section 1: Getting Started
–Section 2: Measurement Concepts and Connections
–Section 3: Measurements and Sourcing Voltage
–Section 4: Range, Units, Digits, Rate, and Filters
–Section 5: Relative, mX+b, m/X+b, and log
–Section 6: Buffer and Sweeps
–Section 7: Triggering
–Section 8: Limit Tests and Digital I/O
–Section 9: Remote Operation
–Section 10: Status Structure
–Section 11: Common Commands
–Section 12: SCPI Signal Oriented Measurement Commands
–Section 13: DISPlay, FORMat, and SYSTem
–Section 14: SCPI Reference Tables
–Section 15: Performance Verification
–Section 16: Calibration
–Section 17: Routine Maintenance
Appendices to this manual contain specifications and also provide additional information
on specific topics. The appendices are organized as follows:
–Appendix A: Specifications
–Appendix B: Status and Error Messages
–Appendix C: DDC Emulation Commands
–Appendix D: IEEE-488 Bus Overview
–Appendix E: IEEE-488 and SCPI Conformance Information
–Appendix F: Remote Calibration
–Appendix G: Applications Guide

Model 6487 Reference Manual Getting Started 1-3
General information
Warranty information
Warranty information is located at the front of this manual. Should your Model 6487
require warranty service, contact the Keithley representative or authorized repair facility in
your area for further information. When returning the instrument for repair, be sure to fill
out and include the service form at the back of this manual to provide the repair facility
with the necessary information.
Contact information
Worldwide phone numbers are listed at the front of this manual. If you have any questions,
please contact your local Keithley representative or call one of our Application Engineers
at 1-800-348-3735 (U.S. and Canada only).
Safety symbols and terms
The following symbols and terms may be found on the instrument or used in this manual:
The symbol on an instrument indicates that the user should refer to the operating
instructions located in the manual.
The symbol on the instrument shows that high voltage may be present on the termi-
nal(s). Use standard safety precautions to avoid personal contact with these voltages.
The symbol on an instrument shows that it can source or measure 1000 volts or more,
including the combined effect of normal and common mode voltages. Use standard safety
precautions to avoid personal contact with these voltages.
The WA R N I N G heading used in this manual explains dangers that might result in per-
sonal injury or death. Always read the associated information very carefully before per-
forming the indicated procedure.
The CAUTION heading used in this manual explains hazards that could damage the
instrument. Such damage may invalidate the warranty.
Unpacking and Inspection
Inspection for damage
The Model 6487 was carefully inspected electrically and mechanically before shipment.
After unpacking all items from the shipping carton, check for any obvious signs of physi-
cal damage that may have occurred during transit. (There may be a protective film over the
display lens, which can be removed.) Report any damage to the shipping agent immedi-
ately. Save the original packing carton for possible future shipment. Before removing the
Model 6487 from the bag, observe the following handling precautions.
!

1-4 Getting Started Model 6487 Reference Manual
Handling precautions
• Always grasp the Model 6487 by the covers.
• After removing the Model 6487 from its anti-static bag, inspect it for any obvious
signs of physical damage. Report any such damage to the shipping agent
immediately.
• When the Model 6487 is not installed and connected, keep the unit in its anti-static
bag and store it in the original packing carton.
Package content
The following items are included with every Model 6487 order:
• Model 6487 Picoammeter with line cord
• Protective triax Shield/Cap (CAP-31)
• 7078-TRX-3 Triax cable
• Model 8607 1kV Source banana cable set
• CS-459 4-Pin Female interlock connector
• Accessories as ordered
• Certificate of calibration
• Model 6487 User’s Manual (P/N 6487-900-00)
• Product information CD-ROM that contains PDFs of the User’s and Reference
Manuals
Reference manual
If a printed copy of the Model 6487 Reference Manual is required, order the manual pack-
age. The Keithley part number for the reference manual package is 6487-901-00. The
manual package includes an instruction manual and any pertinent addenda.
Additional references
While reading this document, you may find it helpful to consult the following documenta-
tion for reference:
Model 6487 User’s Manual — Supplied in printed form and as a PDF on the Product
Information CD-ROM included with your shipment, this manual contains basic operating
information for the user.
Low Level Measurements handbook — Keithley’s guide for effective low current, low
voltage, and high impedance measurements. Refer to www.keithley.com for more details.

Model 6487 Reference Manual Getting Started 1-5
Power-up
Line power connection
Follow the procedure below to connect the Model 6487 to line power and turn on the
instrument.
1. Check to see that the line voltage indicated in the window of the fuse holder assem-
bly (Figure 1-1) is correct for the operating voltage in your area. If not, refer to the
procedure in Section 17 for setting line voltage and fuse replacement.
`^rqflk Operating the instrument on an incorrect line voltage may cause dam-
age to the instrument, possibly voiding the warranty.
Figure 1-1
Rear panel
2. Before plugging in the power cord, make sure that the front panel power switch is
in the off (O) position.
3. Connect the female end of the supplied power cord to the AC receptacle on the rear
panel. Connect the other end of the power cord to a grounded AC outlet.
120
LINE RATING
50, 60Hz
50 VA MAX
INPUT
(CHANGE IEEE ADDRESS
WITH FRONT PANEL MENU)
IEEE-488
CAT I
TRIGGER LINK RS-232
MADE IN
U. S . A .
ANALOG OUT DIGITAL I/O
INTERLOCK
505V
MAX
V-SOURCE OUTPUT
505V PK TO CHASSIS
LO HI
!
!
FUSE LINE
400mAT
(SB)
100 VAC
120 VAC
200mAT
(SB)
220 VAC
240 VAC
505V PK
505V PK
505V PK
PowerModule

1-6 Getting Started Model 6487 Reference Manual
t^okfkd The power cord supplied with the Model 6487 contains a separate
ground wire for use with grounded outlets. When proper connections
are made, instrument chassis is connected to power line ground
through the ground wire in the power cord. Failure to use a grounded
outlet may result in personal injury or death due to electric shock.
4. Turn on the instrument by pressing the front panel power switch to the on (I)
position.
Line frequency
The Model 6487 operates at line frequencies of 50 or 60Hz. When auto detect is enabled
(factory default), line frequencies are automatically sensed and set accordingly, therefore
there are no switches to set. Use the :SYSTem:LFRequency? command (query) to read the
line frequency. The factory default setting is Auto-Detect enabled.
If the power line is noisy, auto detect may not be able to lock in on a frequency. If this
occurs, set the frequency manually. This may be accomplished using the front panel (see
the following procedure) or over the bus. Refer to Table 1-1 for commands.
Front panel procedure
1. Press MENU.
2. Scroll to the LFREQ: menu item using the and RANGE keys. The present set-
ting is displayed.
3. Press the cursor key.
4. Use the and RANGE keys to scroll to the desired menu item:
AUTOXX, 50, or 60
5. Press ENTER.
klqb In the setting of AUTOXX, XX is the currently detected frequency.
SCPI programming — line frequency
Tab le 1- 1
SCPI commands — line frequency
Command Description
SYSTem
:LFRequency <freq>
:AUTO <b>
:AUTO?
[:STATE]
[:STATE]?
:LFRequency?
SYSTem Subsystem:
Set power line frequency (in Hz) to 50 or 60.
Turn automatic frequency detection ON or OFF.
Read the present automatic detected line frequency
state (1 = on, 0 = off).
Read present line frequency setting.

Model 6487 Reference Manual Getting Started 1-7
Power-up sequence
The following power-up sequence occurs when the Model 6487 is turned on:
1. The Model 6487 performs self-tests on its EPROM and RAM with all digits and
annunciators turned on. If a failure is detected, the instrument momentarily dis-
plays an error message and the ERR annunciator turns on. Error messages are
listed in Appendix B.
klqb If a problem develops while the instrument is under warranty, return it to
Keithley Instruments Inc., for repair.
2. If the instrument passes the self-tests, the firmware revision levels are displayed.
For example:
6487 A01
3. After the firmware revision levels are displayed, the detected line frequency is
displayed.
For example:
FREQ: 60Hz
4. After the detected line frequency is displayed, information on the selected remote
interface is displayed:
a. GPIB — If the GPIB is the selected interface, the instrument will display the
selected language (SCPI, 488.1, or DDC) and primary address.
Examples:
SCPI ADDR: 22
DDC ADDR: 22
b. RS-232 — If RS-232 is the selected interface, the instrument will display the
baud rate setting. For example:
RS-232: 9600b
5. If the FACTory setup is selected as the power-on setup, the unit is placed in the
default reading mode after the communication information is displayed. If a setup
other than FACTory is selected, the configured setup will be displayed. For exam-
ple, if the USR1 setup (User Setup #1) is selected:
USING USR1
klqb To configure power-on set up:
1. Display PWR-ON: menu, press CONFIG and then SETUP.
2. Use and RANGE keys to scroll through the menu items.
3. Press ENTER to select or EXIT to quit without changing power-on setup.

1-8 Getting Started Model 6487 Reference Manual
Front panel operation
Figure 1-2 shows the front panel of the Model 6487. For a detailed description of the vari-
ous controls, displays, and indicators, see Section 1 of the Model 6487 User’s Manual.
Figure 1-2
Front panel
Status and error messages
Status and error messages are displayed momentarily. During operation and programming,
you will encounter a number of front panel messages. Typical messages are either of status
or error variety, as listed in Appendix B.
Messages, both status and error, are held in queues. For information on retrieving mes-
sages from queues, see Section 10.
Default settings
The Model 6487 can be restored to one of five setup configurations: factory default
(FACT), three user-saved (USR0, USR1, and USR2), and bus default (GPIB). As shipped
from the factory, the Model 6487 powers up to the factory default settings. Factory default
settings provide a general purpose setup for front panel operation, while the bus default
(GPIB) settings do the same for remote operation. Factory and GPIB default settings are
listed in Table 1-2.
The instrument will power up to whichever default setup was saved as the power-on setup.
klqb At the factory, the factory default setup is saved into the USR0, USR1, and USR2
setups.
6487 PICOAMMETER /VOLTAGE SOURCE
RANGE
AUTO
CONFIG/
LOCAL
MENU
POWER
RANGE
EXIT ENTER
LIMIT RATEDIGITS
STORE RECALL
I| Ω
MATH FILT ZCHK REL OPER
COMM DISPTRIG
AZERO DAMP
SAVE SETUP
V-SOURCE VOLTAGE
SOURCE
OPERATE