Model 2700 Multimeter/
Data Acquisition System
Service Manual
Contains Servicing Information
WARRANTY
Keithley Instruments, Inc. warrants this product to be free from defects in material and workmanship for a
period of 1 year from date of shipment.
Keithley Instruments, Inc. warrants the following items for 90 days from the date of shipment: probes, cables,
rechargeable batteries, diskettes, and documentation.
During the warranty period, we will, at our option, either repair or replace any product that proves to be defective.
To exercise this warranty, write or call your local Keithley representative, or contact Keithley headquarters in
Cleveland, Ohio. You will be given prompt assistance and return instructions. Send the product, transportation
prepaid, to the indicated service facility. Repairs will be made and the product returned, transportation prepaid.
Repaired or replaced products are warranted for the balance of the original warranty period, or at least 90 days.
LIMITATION OF WARRANTY
This warranty does not apply to defects resulting from product modification without Keithley’s express written
consent, or misuse of any product or part. This warranty also does not apply to fuses, software, non-rechargeable batteries, damage from battery leakage, or problems arising from normal wear or failure to follow instructions.
THIS WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE.
THE REMEDIES PROVIDED HEREIN ARE BUYER’S SOLE AND EXCLUSIVE REMEDIES.
NEITHER KEITHLEY INSTRUMENTS, INC. NOR ANY OF ITS EMPLOYEES SHALL BE LIABLE FOR
ANY DIRECT, INDIRECT, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF
THE USE OF ITS INSTRUMENTS AND SOFTWARE EVEN IF KEITHLEY INSTRUMENTS, INC., HAS
BEEN ADVISED IN ADVANCE OF THE POSSIBILITY OF SUCH DAMAGES. SUCH EXCLUDED DAMAGES SHALL INCLUDE, BUT ARE NOT LIMITED TO: COSTS OF REMOVAL AND INSTALLATION,
LOSSES SUSTAINED AS THE RESULT OF INJURY TO ANY PERSON, OR DAMAGE TO PROPERTY.
Keithley Instruments, Inc.
BELGIUM: Keithley Instruments B.V.
CHINA: Keithley Instruments China
FRANCE: Keithley Instruments Sarl
GERMANY: Keithley Instruments GmbH
GREAT BRITAIN: Keithley Instruments Ltd
INDIA: Keithley Instruments GmbH
ITALY: Keithley Instruments s.r.l.
NETHERLANDS: Keithley Instruments B.V.
SWITZERLAND: Keithley Instruments SA
TAIWAN: Keithley Instruments Taiwan
• 28775 Aurora Road • Cleveland, OH 44139 • 440-248-0400 • Fax: 440-248-6168 • http://www.keithley.com
Bergensesteenweg 709 • B-1600 Sint-Pieters-Leeuw • 02/363 00 40 • Fax: 02/363 00 64
Yuan Chen Xin Building, Room 705 • 12 Yumin Road, Dewai, Madian • Beijing 100029 • 8610-62022886 • Fax: 8610-62022892
B.P. 60 • 3, allée des Garays • 91122 Palaiseau Cédex • 01 64 53 20 20 • Fax: 01 60 11 77 26
Landsberger Strasse 65 • D-82110 Germering • 089/84 93 07-40 • Fax: 089/84 93 07-34
The Minster • 58 Portman Road • Reading, Berkshire RG30 1EA • 0118-9 57 56 66 • Fax: 0118-9 59 64 69
Flat 2B, WILOCRISSA • 14, Rest House Crescent • Bangalore 560 001 • 91-80-509-1320/21 • Fax: 91-80-509-1322
Viale S. Gimignano, 38 • 20146 Milano • 02/48 30 30 08 • Fax: 02/48 30 22 74
Postbus 559 • 4200 AN Gorinchem • 0183-635333 • Fax: 0183-630821
Kriesbachstrasse 4 • 8600 Dübendorf • 01-821 94 44 • Fax: 01-820 30 81
1 Fl. 85 Po Ai Street • Hsinchu, Taiwan, R.O.C. • 886-3572-9077• Fax: 886-3572-9031
10/99
Model 2700 Multimeter/Data Aquisition System
Service Manual
©1999, Keithley Instruments, Inc.
All rights reserved.
Cleveland, Ohio, U.S.A.
Second Printing, February 2000
Document Number: 2700-902-01 Rev. B
Manual Print History
The print history shown below lists the printing dates of all Revisions and Addenda created
for this manual. The Revision Level letter increases alphabetically as the manual undergoes
subsequent updates. Addenda, which are released between Revisions, contain important
change information that the user should incorporate immediately into the manual. Addenda
are numbered sequentially. When a new Revision is created, all Addenda associated with the
previous Revision of the manual are incorporated into the new Revision of the manual. Each
new Revision includes a revised copy of this print history page.
Revision A (Document Number 2700-902-01)...........................................................November 1999
Revision B (Document Number 2700-902-01) ............................................................. February 2000
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.
Safety Precautions
The following safety precautions should be observed before using this product and any associated instrumentation. Although some instruments and accessories would normally be used with non-hazardous
voltages, there are situations where hazardous conditions may be present.
This product is intended for use by qualified personnel who recognize shock hazards and are familiar
with the safety precautions required to avoid possible injury. Read the operating information carefully
before using the product.
The types of product users are:
Responsible body
ensuring that the equipment is operated within its specifications and operating limits, and for ensuring
that operators are adequately trained.
Operators
and proper use of the instrument. They must be protected from electric shock and contact with hazardous
live circuits.
Maintenance personnel
setting the line voltage or replacing consumable materials. Maintenance procedures are described in the
manual. The procedures explicitly state if the operator may perform them. Otherwise, they should be
performed only by service personnel.
Service personnel
ucts. Only properly trained service personnel may perform installation and service procedures.
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.
practice is to expect that hazardous voltage is present in any unknown circuit before measuring.
Users of this product must be protected from electric shock at all times. The responsible body must ensure that users are prevented access and/or insulated from every connection point. In some cases, connections must be exposed to potential human contact. Product users 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,
As described in the International Electrotechnical Commission (IEC) Standard IEC 664, digital multimeter measuring circuits (e.g., Keithley Models 175A, 199, 2000, 2001, 2002, and 2010) are Installation
Category II. All other instruments’ signal terminals are Installation Category I and must not be connected to mains.
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, make sure the line cord is connected to a properly grounded power receptacle. Inspect the connecting cables, test leads, and jumpers for possible wear, cracks, or breaks before each use.
For maximum safety, do not touch the product, test cables, or any other instruments while power is applied to the circuit under test. ALWAYS 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.
is the individual or group responsible for the use and maintenance of equipment, for
use the product for its intended function. They must be trained in electrical safety procedures
are trained to work on live circuits, and perform safe installations and repairs of prod-
no conductive part of the circuit may be exposed.
perform routine procedures on the product to keep it operating, for example,
A good safety
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 its 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 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 indicates that the user should refer to the operating instructions located in
the manual.
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
WARNING
read the associated information very carefully before performing the indicated procedure.
heading in a manual explains dangers that might result in personal injury or death. Always
The
CAUTION
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.
heading in a manual explains hazards that could damage the instrument. Such damage may
Rev. 10/99
Table of Contents
1 Performance Verification
Introduction ................................................................................ 1-2
Verification test requirements ..................................................... 1-3
Environmental conditions ................................................... 1-3
Warm-up period .................................................................. 1-3
Line power .......................................................................... 1-3
Recommended test equipment ................................................... 1-4
Verification limits ....................................................................... 1-5
Example reading limit calculation ...................................... 1-5
Calculating resistance reading limits .................................. 1-5
Restoring factory defaults .......................................................... 1-5
Performing the verification test procedures ............................... 1-6
Verification test summary ................................................... 1-6
Test considerations .............................................................. 1-7
Model 2700 verification ............................................................. 1-8
Verifying DC voltage .......................................................... 1-8
Verifying AC voltage ........................................................... 1-9
Verifying DC current ......................................................... 1-11
Verifying AC current ......................................................... 1-12
Verifying resistance ........................................................... 1-13
Verifying temperature ....................................................... 1-15
Verifying frequency .......................................................... 1-17
Model 7700 verification ........................................................... 1-18
Verifying DC voltage ........................................................ 1-18
Verifying AC voltage ......................................................... 1-20
Verifying DC current ......................................................... 1-22
Verifying AC current ......................................................... 1-24
Verifying resistance ........................................................... 1-25
Verifying temperature ....................................................... 1-27
Verifying frequency .......................................................... 1-30
Verifying ratio and average ............................................... 1-30
2 Calibration
Introduction ................................................................................ 2-2
Environmental conditions ........................................................... 2-2
Warm-up period ................................................................... 2-2
Line power ........................................................................... 2-2
Calibration considerations .......................................................... 2-3
Calibration code .......................................................................... 2-4
Front panel calibration code ................................................ 2-4
Remote calibration code ...................................................... 2-4
Comprehensive calibration ......................................................... 2-5
Calibration cycle .................................................................. 2-5
Recommended equipment ................................................... 2-5
Aborting calibration ............................................................ 2-6
Front panel calibration ........................................................ 2-6
Remote calibration ............................................................ 2-13
Manufacturing calibration ........................................................ 2-18
Recommended test equipment .......................................... 2-18
Extender board preparation ............................................... 2-19
Unlocking manufacturing calibration ................................ 2-19
Measuring function generator signal amplitude ................ 2-19
Front panel manufacturing calibration .............................. 2-20
Remote manufacturing calibration .................................... 2-21
Model 7700 calibration ............................................................. 2-22
Recommended test equipment .......................................... 2-22
Extender board connections .............................................. 2-22
Model 7700 calibration ..................................................... 2-22
3 Routine Maintenance
Introduction ................................................................................ 3-2
Setting the line voltage and replacing the line fuse .................... 3-2
Replacing the front terminal AMPS fuse .................................... 3-4
Replacing plug-in module amps fuses ........................................ 3-5
Replacing Model 7700 amps fuses ...................................... 3-5
Replacing Model 7702 amps fuses ...................................... 3-6
Replacing non-volatile RAM battery ......................................... 3-8
4 Troubleshooting
Introduction ................................................................................ 4-2
Repair considerations ................................................................. 4-2
Power-on self-test ....................................................................... 4-2
Front panel tests ......................................................................... 4-3
KEY test .............................................................................. 4-3
DISP test ............................................................................. 4-3
Principles of operation ............................................................... 4-4
Power supply ....................................................................... 4-4
Display board ...................................................................... 4-6
Digital circuitry ................................................................... 4-7
Analog circuitry .................................................................. 4-8
Troubleshooting ....................................................................... 4-11
Display board checks ........................................................ 4-11
Power supply checks ......................................................... 4-11
Digital circuitry checks ..................................................... 4-12
Analog signal switching states .......................................... 4-13
No comm link error .................................................................. 4-18
5 Disassembly
Introduction ................................................................................ 5-2
Handling and cleaning ............................................................... 5-2
Handling PC boards ............................................................ 5-2
Solder repairs ...................................................................... 5-2
Static sensitive devices ........................................................ 5-3
Assembly drawings .................................................................... 5-3
Disassembly procedures ............................................................. 5-4
Case cover removal ............................................................. 5-4
Motherboard removal .......................................................... 5-4
Card cage removal .............................................................. 5-5
Front panel disassembly ...................................................... 5-6
Removing power components ............................................. 5-6
Instrument reassembly ............................................................... 5-7
Input terminal wire connections .......................................... 5-7
Power module wire connections ......................................... 5-7
6 Replaceable Parts
Introduction ................................................................................ 6-2
Parts lists .................................................................................... 6-2
Ordering information ................................................................. 6-2
Factory service ........................................................................... 6-2
Component layouts .................................................................... 6-2
A Specifications
Accuracy calculations .............................................................. A-12
Calculating DC characteristics accuracy .......................... A-12
Calculating AC characteristics accuracy .......................... A-12
Calculating dBm characteristics accuracy ........................ A-13
Calculating dB characteristics accuracy ........................... A-13
Additional derating factors ............................................... A-14
Optimizing measurement accuracy ......................................... A-14
DC voltage, DC current, and resistance: .......................... A-14
AC voltage and AC current: ............................................. A-14
Temperature: ..................................................................... A-14
Optimizing measurement speed .............................................. A-15
DC voltage, DC current, and resistance: .......................... A-15
AC voltage and AC current: ............................................. A-15
Temperature: ..................................................................... A-15
B Calibration Reference
Introduction ............................................................................... B-2
Command summary ................................................................... B-2
Miscellaneous calibration commands ........................................ B-4
:CODE ................................................................................ B-4
:COUNt? ............................................................................. B-4
:INIT ................................................................................... B-5
:LOCK ................................................................................ B-5
:LOCK? .............................................................................. B-6
:SAVE ................................................................................. B-6
:DATE ................................................................................. B-7
:NDUE ................................................................................ B-7
DC calibration commands ......................................................... B-8
:STEP1 ............................................................................... B-8
:STEP2 ............................................................................... B-9
:STEP3 ............................................................................... B-9
:STEP4 ............................................................................... B-9
:STEP5 ............................................................................. B-10
:STEP6 ............................................................................. B-10
:STEP7 ............................................................................. B-10
:STEP8 ............................................................................. B-11
:STEP9 ............................................................................. B-11
:STEP10 ........................................................................... B-11
:STEP11 ........................................................................... B-12
:STEP12 ........................................................................... B-12
AC calibration commands ....................................................... B-13
:AC:STEP<n> .................................................................. B-14
Manufacturing calibration commands ..................................... B-15
:AC:STEP<14|15> ........................................................... B-15
:DC:STEP0 ...................................................................... B-15
Model 7700 calibration commands ......................................... B-16
:CODE .............................................................................. B-17
:COUNt? .......................................................................... B-17
:DATE? ............................................................................. B-18
:INIT ................................................................................ B-18
:LOCK .............................................................................. B-19
:LOCK? ............................................................................ B-19
:RCOunt ........................................................................... B-19
:SAVE .............................................................................. B-20
:STEP0 ............................................................................. B-20
Remote error reporting ............................................................ B-21
Error summary ................................................................. B-21
Error queue ....................................................................... B-23
Status byte EAV (Error Available) bit .............................. B-23
Generating an SRQ on error ............................................ B-23
Detecting calibration step completion ..................................... B-23
Using the *OPC? query ................................................... B-23
Using the *OPC command ............................................... B-24
Generating an SRQ on calibration complete ................... B-24
C Calibration Program
Introduction ............................................................................... C-2
Computer hardware requirements ............................................. C-2
Software requirements .............................................................. C-2
Calibration equipment ............................................................... C-2
General program instructions .................................................... C-3
List of Illustrations
1 Performance Verification
Figure 1-1 Connections for Model 2700 DC volts verification ................1-8
Figure 1-2 Connections for Model 2700 AC volts verification .................1-9
Figure 1-3 Connections for Model 2700 DC current verification ...........1-11
Figure 1-4 Connections for Model 2700 AC current verification ...........1-12
Figure 1-5 Connections for Model 2700 resistance
verification (100Ω to 10MΩ ranges) ...............................1-13
Figure 1-6 Connections for Model 2700 resistance
verification (100MΩ range) .............................................1-14
Figure 1-7 Connections for Model 2700 frequency verification .............1-17
Figure 1-8 Connections for Model 7700 DC volts verification ..............1-18
Figure 1-9 Connections for Model 7700 AC volts verification ...............1-20
Figure 1-10 Connections for Model 7700 DC current verification ...........1-22
Figure 1-11 Connections for Model 7700 AC current verification ...........1-24
Figure 1-12 Connections for Model 7700 resistance
verification (100Ω to 10MΩ ranges) ...............................1-25
Figure 1-13 Connections for Model 7700 resistance
verification (100MΩ range) .............................................1-26
Figure 1-14 Connections for Model 7700 thermocouple
temperature verification ...................................................1-28
Figure 1-15 Connections for Model 7700 frequency verification .............1-30
Figure 1-16 Connections for Model 7700 ratio and
average verification ..........................................................1-31
2 Calibration
Figure 2-1 Low-thermal short connections ...............................................2-7
Figure 2-2 Connections for DC volts and ohms calibration .....................2-8
Figure 2-3 Connections for DC and AC amps calibration ......................2-10
Figure 2-4 Connections for AC volts calibration ....................................2-11
Figure 2-5 Function generator connections for
manufacturing calibration ................................................2-20
3 Routine Maintenance
Figure 3-1 Power module ..........................................................................3-3
Figure 3-2 Front terminal AMPS fuse ......................................................3-4
Figure 3-3 Model 7700 amps fuses ...........................................................3-5
Figure 3-4 Model 7702 amps fuses ...........................................................3-7
4 Troubleshooting
Figure 4-1 Power supply block diagram ................................................... 4-4
Figure 4-2 Digital circuitry block diagram ............................................... 4-6
Figure 4-3 Analog circuitry block diagram .............................................. 4-9
C Calibration Program
Figure C-1 Model 2700 calibration program ........................................... C-3
List of Tables
1 Performance Verification
Table 1-1 Recommended verification equipment ....................................1-4
Table 1-2 DCV reading limits .................................................................1-9
Table 1-3 ACV reading limits ...............................................................1-10
Table 1-4 DCI limits ..............................................................................1-11
Table 1-5 ACI limits ..............................................................................1-12
Table 1-6 Limits for resistance verification ...........................................1-14
Table 1-7 Thermocouple temperature verification reading limits .........1-16
Table 1-8 Four-wire RTD temperature verification reading limits ........1-17
Table 1-9 Plug-in module DCV reading limits .....................................1-19
Table 1-10 Plug-in module ACV reading limits ......................................1-21
Table 1-11 Plug-in module DCI limits ....................................................1-23
Table 1-12 Plug-in module ACI limits ....................................................1-24
Table 1-13 Limits for plug-in module resistance verification .................1-27
Table 1-14 Model 7700 thermocouple temperature verification
Table 1-15 Plug-in module four-wire RTD temperature
2 Calibration
Table 2-1 Recommended equipment for comprehensive calibration ......2-5
Table 2-2 Comprehensive calibration procedures ...................................2-7
Table 2-3 DC volts calibration summary .................................................2-9
Table 2-4 Ohms calibration summary .....................................................2-9
Table 2-5 DC current calibration summary ...........................................2-10
Table 2-6 AC voltage calibration summary ...........................................2-11
Table 2-7 AC current calibration summary ...........................................2-12
Table 2-8 DC voltage calibration programming steps ...........................2-15
Table 2-9 Resistance calibration programming steps ............................2-15
Table 2-10 DC current calibration programming steps ...........................2-16
Table 2-11 AC voltage calibration programming steps ...........................2-17
Table 2-12 AC current calibration programming steps ...........................2-17
Table 2-13 Recommended equipment for manufacturing calibration .....2-18
Table 2-14 Recommended equipment for Model 7700 calibration .........2-22
reading limits ...................................................................1-28
verification reading limits ................................................1-29
3 Routine Maintenance
Table 3-1 Power line fuse ........................................................................3-3
4 Troubleshooting
Table 4-1 Power supply components ...................................................... 4-5
Table 4-2 Display board checks ............................................................ 4-11
Table 4-3 Power supply checks ............................................................. 4-11
Table 4-4 Digital circuitry checks .........................................................4-12
Table 4-5 DCV signal switching ...........................................................4-13
Table 4-6 ACV and FREQ signal switching .........................................4-13
Table 4-7
Table 4-8
Table 4-9
Table 4-10 DCA signal switching ...........................................................4-15
Table 4-11 ACA signal switching ...........................................................4-15
Table 4-12 DCV signal multiplexing and gain .......................................4-16
Table 4-13 ACV and ACA signal multiplexing and gain ........................4-16
Table 4-14 DCA signal multiplexing and gain .......................................4-16
Table 4-15
Table 4-16
Table 4-17 Switching device locations ...................................................4-17
Ω
2 signal switching .............................................................. 4-14
Ω
4 signal switching .............................................................. 4-14
Ω2/Ω
4 reference switching ................................................... 4-14
Ω
2 signal multiplexing and gain ........................................... 4-17
Ω
4 signal multiplexing and gain ........................................... 4-17
5 Disassembly
Table 5-1 Input terminal wire colors ....................................................... 5-7
Table 5-2 Power module wire colors ......................................................5-7
6 Replaceable Parts
Table 6-1 Model 2700 motherboard parts list .........................................6-3
Table 6-2 Model 2700 display board parts list ........................................ 6-8
Table 6-3 Model 2700 connector board parts list ...................................6-9
Table 6-4 Model 2700 miscellaneous parts list ..................................... 6-10
Table 6-5 Model 7700 parts list ............................................................6-11
Table 6-6 Model 7702 parts list ............................................................6-12
Table 6-7 Model 7703 parts list ............................................................6-13
Table 6-8 Model 7705 parts list ............................................................6-14
B Calibration Reference
Table B-1 Remote calibration command summary ................................ B-2
Table B-2 DC calibration commands ..................................................... B-8
Table B-3 AC calibration commands .................................................... B-13
Table B-4 Model 7700 calibration commands ...................................... B-16
Table B-5 Calibration error summary ................................................... B-21
1
Performance Verification
1-2 Performance Verification
Introduction
Use the procedures in this section to verify that Model 2700 Multimeter/Data Acquisition
System accuracy is within the limits stated in the instrument’s one-year accuracy specifications.
You can perform these verification procedures:
• When you first receive the instrument to make sure that it was not damaged during shipment, and that the unit meets factory specifications.
• If the instrument’s accuracy is questionable.
• Following calibration.
WARNING
NOTE
There are three general verification procedures in this section:
•
Model 2700 verification
Model 2700 using the front panel terminals.
Model 7700 verification
•
made through the Model 7700 20-Channel Multiplexer. Note that the same general procedures can be used to verify measurement accuracy of other Model 2700 plug-in modules that have similar functions. For specific information about the individual modules,
refer to the appropriate appendices in the Model 2700 User’s Manual.
The information in this section is intended only for qualified service personnel. Do not attempt these procedures unless you are qualified to do so.
If the instrument is still under warranty and its performance is outside specified limits, contact your Keithley representative or the factory to determine the correct
course of action. If the unit is not under warranty, and it fails to meet specified limits,
refer to the calibration procedures in Section 2.
: Covers procedures to verify measurement accuracy of the
: Discusses procedures to verify accuracy of measurement
Verification test requirements
Be sure that you perform the verification tests:
• Under the proper environmental conditions.
• After the specified warm-up period.
• Using the correct line voltage.
• Using the proper calibration equipment.
• Using the specified reading limits.
Environmental conditions
Conduct your performance verification procedures in a test environment that has:
• An ambient temperature of 18° to 28°C (65° to 82°F).
• A relative humidity of less than 80% unless otherwise noted.
Warm-up period
Allow the Model 2700 to warm up for at least two hours before conducting the verification
procedures.
Performance Verification 1-3
If the instrument has been subjected to temperature extremes (those outside the ranges stated
above), allow additional time for the instrument’s internal temperature to stabilize. Typically,
allow one extra hour to stabilize a unit that is 10°C (18°F) outside the specified temperature
range.
Also, allow the test equipment to warm up for the minimum time specified by the
manufacturer.
Line power
The Model 2700 requires a line voltage of 100V/120V/220V/240V, ±10% and a line
frequency of 45Hz to 66Hz. Note that the line frequency is automatically sensed at power-up,
but the line voltage must be manually set to either 100V/120V or 220V/240V as described in
Section 3.
1-4 Performance Verification
Recommended test equipment
Table 1-1 summarizes recommended verification equipment. You can use alternate
equipment as long as that equipment has specifications at least as good as those listed in
Table 1-1. Keep in mind, however, that calibrator uncertainty will add to the uncertainty of each
measurement.
Table 1-1
Recommended verification equipment
Fluke 5700A Calibrator:
AC voltage
DC voltage
100mV:±14ppm
1.0V:±7ppm
10V:±5ppm
100V:±7ppm
1000V:±9ppm
Fluke 5725A Amplifier:
AC Voltage, 50kHz: 700V, ±375ppm
DC Current, 3A, ±500ppm
AC Current, 1kHz, 3A, ±457ppm
Keithley 3930A or 3940 Frequency Synthesizer:
1V RMS, 10V RMS, 1kHz, ±5ppm, steady state and burst modulation
General Radio 1433-T Precision Decade Resistance Box:
Ω
to 400Ω, ±0.02%
10
Miscellaneous Equipment:
Double banana plug to double banana plug shielded cables (2)
BNC to double banana plug shielded cable
NOTE: The Fluke 5725A amplifier is necessary only if you wish to verify the 750V AC range at 50kHz and 3A AC and DC current
ranges at 3A. Verification at 220V, 50kHz, and 2.2A on the current ranges using only the 5700A calibrator is adequate for
most applications.
(1kHz, 50kHz) DC current
100mV:±200ppm
1.0V:±82ppm
10V:±82ppm
100V:±90ppm
700V:±85ppm
10mA:±60ppm
100mA:±70ppm
1A:±110ppm
2.2A:±94ppm
AC current
(1kHZ) Resistance
1A:±690ppm
2.2A:±682ppm
100
Ω
1k
Ω
10k
Ω
100k
1M
Ω
10M
100M
:±17ppm
:±12ppm
:±11ppm
Ω
:±13ppm
:±18ppm
Ω
:±37ppm
Ω
:±120ppm
Verification limits
The verification limits stated in this section have been calculated using only the Model 2700
one-year accuracy specifications, and they do not include test equipment uncertainty. If a particular measurement falls slightly outside the allowable range, recalculate new limits based on
both Model 2700 specifications and pertinent calibration equipment specifications.
Example reading limit calculation
The following is an example of how reading limits have been calculated. Assume you are
testing the 10V DC range using a 10V input value. Using the Model 2700 one-year accuracy
specification for 10V DC of ± (30ppm of reading + 5ppm of range), the calculated limits are:
Performance Verification 1-5
Reading limits = 10V ± [(10V
Reading limits = 10V ± (0.0003 + 0.00005)
Reading limits = 10V ± 0.00035V
Reading limits = 9.99965V to 10.00035V
Calculating resistance reading limits
Resistance reading limits must be recalculated based on the actual calibration resistance values supplied by the equipment manufacturer. Calculations are performed in the same manner as
shown in the preceding example, except, of course, that you should use the actual calibration
resistance values instead of the nominal values when performing your calculations.
For example, assume that you are testing the 10k
tion resistance value. Using Model 2700 one-year 10k
ing + 6ppm of range), the calculated reading limits are:
Reading limits = 10.03k
Reading limits = 10.02894k
Ω
± [(10.03kΩ × 100ppm) + (10kΩ × 6ppm)]
Ω
Restoring factory defaults
Before performing the verification procedures, restore the instrument to its factory defaults
as follows:
×
30ppm) + (10V × 5ppm)]
Ω
range using an actual 10.03kΩ calibra-
Ω
to 10.03106k
Ω
range accuracy of ± (100ppm of read-
1. Press
2. Using either range key, select FACT, then restore the factory default conditions by
SHIFT
and then
RESTORE: FACT.
pressing
ENTER
.
SETUP
. The instrument will display the following prompt:
1-6 Performance Verification
Performing the verification test procedures
Verification test summary
Verification tests can be performed either through the Model 2700 front panel terminals or
through plug-in modules. This section contains the following procedures:
•
Model 2700 verification
front panel terminals.
Model 7700 verification
•
available plug-in modules with the same functions as the Model 7700 20-Channel
Multiplexer Card.
Model 2700 tests
Model 2700 verification test procedures include:
• DC volts
• AC volts
• DC current
• AC current
• Resistance
• Temperature
• Frequency
: Use this procedure to test Model 2700 accuracy through the
: Use this procedure to test accuracy through any of the
Model 7700 tests
Model 7700 verification test procedures include:
• DC volts
• AC volts
• DC current
• AC current
• Resistance
• Temperature
• Frequency
• Ratio and average
Test considerations
When performing the verification procedures:
• Be sure to restore factory defaults as outlined above.
• Make sure that the equipment is properly warmed up and connected to the correct input
terminals. Also make sure that the INPUTS switch is in the correct position.
• Do not use autoranging for any verification tests because autorange hysteresis may
cause the Model 2700 to be on an incorrect range. For each test signal, you must manually set the correct range for the Model 2700 using the range keys.
• Make sure the calibrator is in operate before you verify each measurement.
• Always let the source signal settle before taking a reading.
Performance Verification 1-7
WARNING
Observe the following safety precautions when performing these tests:
•
Some of the procedures in this section may expose you to dangerous
voltages. Use standard safety precautions when such dangerous voltages are encountered to avoid personal injury or death caused by electric shock.
•
For the front panel terminals only, the maximum common-mode voltage (voltage between INPUT LO and chassis ground) is 500V peak.
Exceeding this value may cause a breakdown in insulation, creating a
shock hazard.
•
For the plug-in modules, the maximum common-mode voltage (voltage between any plug-in module terminal and chassis ground) is 300V
DC or 300V RMS. Exceeding this value may cause a breakdown in
insulation, creating a shock hazard.
•
When using the front panel terminals simultaneously with plug-in
modules, all cable insulation voltage ratings must equal or exceed the
maximum voltage applied to either the front panel terminals or the
plug-in module terminals.
1-8 Performance Verification
Model 2700 verification
Perform these tests to verify accuracy using the Model 2700 front panel terminals.
Verifying DC voltage
Check DC voltage accuracy by applying accurate voltages from the DC voltage calibrator to
the Model 2700 INPUT jacks and verifying that the displayed readings fall within specified
limits.
CAUTION
Do not exceed 1000V peak between front terminals INPUT HI and
INPUT LO because instrument damage may occur.
Follow these steps to verify DC voltage accuracy:
1. Connect the Model 2700 HI and LO INPUT jacks to the DC voltage calibrator as
shown in Figure 1-1. Make sure the INPUTS switch is set to the FRONT position.
NOTE
Use shielded, low-thermal connections when testing the 100mV and 1V ranges to
avoid errors caused by noise or thermal effects. Connect the shield to the calibrator’s output LO terminal.
Figure 1-1
Connections for Model 2700 DC volts verification
Model 2700
LOCAL
POWER
Integra Series
Model 2700 Multimeter / Data Acquisition System
CONT
LIMITS ON/OFFDELAY
RECALL
STEP SCAN
CH AVG
OCOMP
PERIOD SENSOR
Ω2 Ω4
TYPE
TEST
DIGITS RATE
MONITOR
LSYNC
FREQ
TEMP
CH-OFF CARD
RELFILTER
RS-232
GPIB
EXIT ENTER
ACI
RATIO
MATH
OUTPUT
SHIFT
DCV
ACV
DCI
HOLD
TRIG
EX TRIG
STORE
SAVE SETUP
CONFIG HALT
CLOSE
OPEN
RANGE
RANGE
SENSE
INPUT
Ω 4 WIRE
HI
350V
1000V
!
PEAK
PEAK
LO
500V
PEAK
INPUTS
F
R
AUTO
FRONT/REAR
3A 250V
AMPS
Input HI
Output HI
Input
LO
Output
LO
Calibrator (Output DC Voltage)
Note: Use shielded, low-thermal cables
for 100mV and 1V ranges.
2. Select the DC volts function by pressing the
DCV
key, and set the Model 2700 to the
100mV range.
3. Set the calibrator output to 0.00000mV DC, and allow the reading to settle.
4. Enable the Model 2700 REL mode. Leave REL enabled for the remainder of the DC
volts verification tests.
5. Source positive and negative and full-scale voltages for each of the ranges listed in
Table 1-2. For each voltage setting, be sure that the reading is within stated limits.
Table 1-2
DCV reading limits
Range Applied DC voltage* Reading limits (1 year, 18° to 28°C)
100mV
1V
10V
100V
1000V
*Source positive and negative values for each range.
100.0000mV
1.000000V
10.00000V
100.0000V
1000.000V
Verifying AC voltage
Check AC voltage accuracy by applying accurate AC voltages at specific frequencies from
the AC voltage calibrator to the Model 2700 inputs and verifying that the displayed readings
fall within specified ranges.
Performance Verification 1-9
99.9935 to 100.0065mV
0.999963 to 1.000037V
9.99965 to 10.00035V
99.9946 to 100.0054V
999.931 to 1000.069V
CAUTION
Do not exceed 1000V peak between front terminals INPUT HI and
INPUT LO, or 8
Follow these steps to verify AC voltage accuracy:
1. Connect the Model 2700 HI and LO INPUT jacks to the AC voltage calibrator as shown
in Figure 1-2. Be sure the INPUTS switch is in the FRONT position.
Figure 1-2
Connections for Model 2700 AC volts verification
Note: Amplifier required only
for 700V, 50kHz output.
Model 2700
POWER
Integra Series
Model 2700 Multimeter / Data Acquisition System
CONT
CH AVG
RECALL
OCOMP
PERIOD SENSOR
Ω2 Ω4
TYPE
TEST
DIGITS RATE
MONITOR
LSYNC
FREQ
TEMP
CH-OFF CARD
RELFILTER
RS-232
GPIB
EXIT ENTER
ACI
RATIO
MATH
OUTPUT
SHIFT
DCV
ACV
DCI
HOLD
EX TRIG
SAVE SETUP
OPEN
TRIG
CLOSE
LIMITS ON/OFFDELAY
STORE
CONFIG HALT
STEP SCAN
LOCAL
RANGE
RANGE
SENSE
INPUT
Ω 4 WIRE
HI
350V
1000V
!
PEAK
PEAK
LO
500V
PEAK
INPUTS
F
R
AUTO
FRONT/REAR
3A 250V
AMPS
Shielded cable
×
107 V•Hz input, because instrument damage may occur.
Amplifier (Connect to calibrator)
Input HI
Output HI
Input
LO
Output
LO
Calibrator (Output AC Voltage)
1-10 Performance Verification
2. Select the AC volts function by pressing the
ACV
key.
3. Set the Model 2700 for the 100mV range; make sure that REL is disabled.
4. Source 1kHz and 50kHz AC voltages for each of the ranges summarized in Table 1-3,
and make sure that the respective Model 2700 readings fall within stated limits.
Table 1-3
ACV reading limits
ACV
range
100mV
1V
10V
100V
750V
* If the 5725A amplifier is not available, change the 700V @ 50kHz step to 220V @ 50kHz. Reading
limits for 220V @ 50kHz = 219.36 to 220.64V.
Applied AC
voltage
100.0000mV
1.000000V
10.00000V
100.0000V
700.000V*
1kHz reading limits
(1 year, 18°C to 28°C)
99.910 to 100.090mV
0.99910 to 1.00090V
9.9910 to 10.0090V
99.910 to 100.090V
699.36 to 700.64V
50kHz reading limits
(1 year, 18°C to 28°C)
99.830 to 100.170mV
0.99830 to 1.00170V
9.98300 to 10.0170V
99.830 to 100.170V
698.79 to 701.21V
Verifying DC current
Check DC current accuracy by applying accurate DC currents from the DC current calibrator to the AMPS input of the Model 2700 and verifying that the displayed readings fall within
specified limits.
Follow these steps to verify DC current accuracy:
1. Connect the Model 2700 AMPS and INPUT LO jacks to the calibrator as shown in
Figure 1-3. Be sure the INPUTS switch is in the FRONT position.
Figure 1-3
Connections for Model 2700 DC current verification
Model 2700
POWER
Integra Series
Model 2700 Multimeter / Data Acquisition System
CONT
RECALL
CH AVG
OCOMP
PERIOD SENSOR
Ω2 Ω4
TYPE
TEST
DIGITS RATE
MONITOR
FREQ
TEMP
CH-OFF CARD
RELFILTER
LSYNC
RS-232
GPIB
EXIT ENTER
ACI
RATIO
MATH
OUTPUT
SHIFT
DCV
ACV
DCI
HOLD
EX TRIG
SAVE SETUP
OPEN
TRIG
CLOSE
LIMITS ON/OFFDELAY
STORE
CONFIG HALT
STEP SCAN
LOCAL
RANGE
RANGE
SENSE
INPUT
Ω 4 WIRE
HI
350V
1000V
!
PEAK
PEAK
LO
500V
PEAK
INPUTS
F
R
AUTO
FRONT/REAR
3A 250V
AMPS
Input
LO
Output HI
Amps
Output
LO
Performance Verification 1-11
Calibrator (Output DC Current)
Note: Be sure calibrator is set for
normal current output.
2. Select the DC current measurement function by pressing the
DCI
key.
3. Set the Model 2700 for the 20mA range.
4. Source positive and negative full-scale currents for each of the ranges listed in
Table 1-4, and verify that the readings for each range are within stated limits.
Table 1-4
DCI limits
DCI range Applied DC current* Reading limits (1 year, 18°C to 28°C)
20mA
100mA
1A
3A
20.0000mA
100.0000mA
1.000000A
3.000000A**
* Source positive and negative currents with values shown.
** If the Fluke 5725 amplifier is not available, apply 2.2A from calibrator. Reading limits for 2.2A
input are: 2.197240 to 2.202760A.
19.89960 to 20.01040mA
99.9100 to 100.0900mA
0.999160 to 1.000840A
2.99628 to 3.00372A
1-12 Performance Verification
Verifying AC current
Check AC current accuracy by applying accurate AC voltage current at specific frequencies
from the AC current calibrator to the Model 2700 input, and verifying that the displayed readings fall within specified limits. Follow these steps to verify AC current:
1. Connect the Model 2700 AMPS and INPUT LO jacks to the calibrator as shown in
Figure 1-4. Be sure the INPUTS switch is in the FRONT position.
Figure 1-4
Connections for Model 2700 AC current verification
Model 2700
POWER
Integra Series
Model 2700 Multimeter / Data Acquisition System
CONT
CH AVG
RECALL
OCOMP
PERIOD SENSOR
Ω2 Ω4
TYPE
TEST
DIGITS RATE
MONITOR
FREQ
TEMP
CH-OFF CARD
RELFILTER
RS-232
LSYNC
GPIB
EXIT ENTER
ACI
RATIO
MATH
OUTPUT
SHIFT
DCV
ACV
DCI
HOLD
EX TRIG
SAVE SETUP
OPEN
TRIG
CLOSE
LIMITS ON/OFFDELAY
STORE
CONFIG HALT
STEP SCAN
LOCAL
RANGE
RANGE
SENSE
INPUT
Ω 4 WIRE
HI
350V
1000V
!
PEAK
PEAK
LO
500V
PEAK
INPUTS
F
R
AUTO
FRONT/REAR
3A 250V
AMPS
Output HI
Input
LO
Output
LO
Calibrator (Output AC Current)
Amps
2. Select the AC current function by pressing the ACI key.
3. Set the Model 2700 for the 1A range.
4. Source 1A and 3A, 1kHz full-scale AC currents as summarized in Table 1-5, and verify
that the readings are within stated limits.
Table 1-5
ACI limits
ACV range Applied AC voltage Reading limits @ 1kHz (1 year, 18°C to 28°C)
1A
3A
* If the Fluke 5725A amplifier is not available, apply 2.2A from the calibrator. Reading limits for 2.2A are
2.1949 to 2.2051A.
1.000000A
3.00000A*
0.99860 to 1.00140A
2.9937 to 3.0063A
Verifying resistance
Check resistance by connecting accurate resistance values to the Model 2700 and verifying
that its resistance readings are within the specified limits.
CAUTION Do not apply more than 1000V peak between front terminals INPUT HI
and LO or more than 350V peak between SENSE HI and LO, or instrument damage could occur.
Follow these steps to verify resistance accuracy:
1. Using shielded, Teflon-insulated or equivalent cables in a 4-wire configuration, connect
the Model 2700 INPUT and SENSE jacks to the calibrator as shown in Figure 1-5. Be
sure the INPUTS switch is in the FRONT position.
Figure 1-5
Connections for Model 2700 resistance verification (100Ω to 10MΩ ranges)
Performance Verification 1-13
LOCAL
POWER
Sense HI
Sense HI
Resistance Calibrator
Model 2700
Integra Series
SENSE
INPUT
Ω 4 WIRE
HI
350V
!
RANGE
RANGE
PEAK
LO
INPUTS
F
R
AUTO
FRONT/REAR
3A 250V
AMPS
Model 2700 Multimeter / Data Acquisition System
CONT
CH AVG
RECALL
OCOMP
PERIOD SENSOR
Ω2 Ω4
TYPE
TEST
DIGITS RATE
MONITOR
LSYNC
FREQ
TEMP
CH-OFF CARD
RELFILTER
RS-232
GPIB
EXIT ENTER
ACI
RATIO
MATH
OUTPUT
SHIFT
DCV
ACV
DCI
HOLD
LIMITS ON/OFFDELAY
TRIG
EX TRIG
STORE
SAVE SETUP
CONFIG HALT
CLOSE
OPEN
STEP SCAN
Input
HI
1000V
PEAK
500V
PEAK
Input
LO
Output
HI
Output
LO
Sense LO
Sense LO
Note: Use shielded low-thermal cables to
minimize noise. Enable or disable
calibrator external sense as indicated
in procedure.
2. Set the calibrator for 4-wire resistance with external sense on.
3. Select the Model 2700 4-wire resistance function by pressing the Ω4 key, then choose
the SLOW integration rate with the RATE key.
4. Set the Model 2700 for the 100Ω range, and make sure the FILTER is on. Enable
OCOMP (offset-compensated ohms) for 100Ω range verification. (Press SHIFT then
OCOMP.)
5. Recalculate reading limits based on actual calibrator resistance values.
1-14 Performance Verification
6. Source the nominal full-scale resistance values for the 100Ω-10MΩ ranges summarized
in Table 1-6, and verify that the readings are within calculated limits.
7. Connect the Model 2700 INPUT and SENSE jacks to the calibrator as shown in
Figure 1-6.
8. Disable external sense on the calibrator.
9. Set the Model 2700 for the 100MΩ range.
10. Source a nominal 100MΩ resistance value, and verify that the reading is within calculated limits for the 100MΩ range.
Figure 1-6
Connections for Model 2700 resistance verification (100MΩ range)
Model 2700
Model 2700 Multimeter / Data Acquisition System
CONT
CH AVG
RECALL
OCOMP
PERIOD SENSOR
Ω2 Ω4
TYPE
TEST
DIGITS RATE
MONITOR
LSYNC
FREQ
TEMP
CH-OFF CARD
RELFILTER
RS-232
GPIB
EXIT ENTER
ACI
POWER
RATIO
MATH
OUTPUT
SHIFT
DCV
ACV
DCI
HOLD
EX TRIG
SAVE SETUP
OPEN
CLOSE
LIMITS ON/OFFDELAY
TRIG
STORE
CONFIG HALT
STEP SCAN
LOCAL
Sense LO
Table 1-6
Limits for resistance verification
Nominal
Ω Range
100Ω∗
1kΩ
10kΩ
100kΩ
1MΩ
10MΩ
100MΩ
resistance
100Ω
1kΩ
10kΩ
100kΩ
1MΩ
10MΩ
100MΩ
Integra Series
RANGE
AUTO
RANGE
Sense HI
SENSE
Ω 4 WIRE
HI
350V
!
PEAK
LO
INPUTS
F
R
FRONT/REAR
INPUT
3A 250V
AMPS
Input
HI
1000V
PEAK
500V
PEAK
Input
LO
Output
HI
Output
LO
Calibrator (Output 2-wire Resistance)
Note: Use shielded cables to minimize noise.
Disable calibrator external sense mode.
Nominal reading limits
(1 year, 18°C to 28°C) Recalculated limits**
99.9884 to 100.0116Ω
0.999894 to 1.000106kΩ
9.99894 to 10.00106kΩ
99.9890 to 100.0110kΩ
0.999890 to 1.000110MΩ
9.99590 to 10.00410MΩ
99.7970 to 100.2030MΩ
__________ to __________ Ω
__________ to __________ kΩ
__________ to __________ kΩ
__________ to __________ kΩ
__________ to __________ MΩ
__________ to __________ MΩ
__________ to __________ MΩ
* Enable O COMP (offset-compensated ohms) when testing 100Ω range.
** Calculate limits based on actual calibration resistance values and Model 2700 one-year resistance accuracy specifications. See
Verification limits.
Loading...