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 Keithle y representative, or contact Keithle y headquarters in Cleveland, Ohio. Y ou 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.
LIMIT A TION OF W ARRANTY
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.
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 2001-SCAN-901-01)..................................................................... April 1992
Addendum A (Document Number 2001-SCAN-901-02)................................................................. May 1992
Revision B (Document Number 2001-SCAN-901-01) .......................................................................June 1992
Addendum B (Document Number 2001-SCAN-901-02)........................................................... October 1995
Revision C (Document Number 2001-SCAN-901-01).......................................................................June 1998
All Keithley product names are trademarks or registered trademarks of Keithley Instruments, Inc.
Other brand and product 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 is the individual or group responsible for the use
and maintenance of equipment, 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, for example, 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 are trained to work on live circuits, and perform
safe installations and repairs of products. 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. A good safety practice is to expect
that hazardous voltage is present in any unknown circuit bef ore
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, no conductive part of the circuit may be
exposed.
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)
measuring circuits 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.
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.
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 heading in a manual explains dangers that might
result in personal injury or death. Alw ays read the associated infor mation very carefully before performing the indicated procedure.
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 the 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.
The CAUTION heading in a manual explains hazards that could
damage the instrument. Such damage may invalidate the warranty.
SCANNER OPTION 2001-SCAN
GENERAL
10 Channels: 8 channels of 2-pole relay input.
CAPABILITIES
a. Multiplex one of ten 2-pole or one of five 4-pole signals into DMM and/or
any combination of 2 or 4-pole signals, or
b. Two channel, high speed multiplexing into the DMM, or
c. High speed ratio or delta measurements.
FUNCTIONS (can be mixed from channel to channel)
Relay Channels:YesYes*Yes
Solid State Channels:Yes——
*On 2 channels, using user-supplied
RELAY INPUTS
Maximum Signal Level:
DC Signals: 110V DC, 1A switched, 30VA maximum (resistive load).
AC Signals: 125V AC rms or 175V AC peak, 100kHz maximum, 1A switched,
62.5VA maximum (resistive load).
Contact Life: >10
switching.
Contact Resistance: <1
Actuation Time: 2.5ms maximum on/off.
2 channels of 2-pole solid state input.
All channels configurable to 4-pole.
Ω
DCV, ACV, 4-Wire
,2-Wire
4-Wire RTD, FrequencyDCI, ACI2-Wire RTD
1
⁄4W shunt resistor.
5
operations at maximum signal level; >108 operations cold
Ω
at end of contact life.
Ω
SOLID STATE INPUTS
Ω
Resistance: <275
(including 200Ω series resistor).
Maximum Signal Level: 110V DC, 175V peak AC, 50mA, 100kHz maximum.
µ
Actuation Time: 150
s maximum on, 100µs maximum off.
ALL INPUTS
±
Contact Potential: <
500nV typical per contact, 1µV max.
±
500nV typical per contact pair, 1µV max.
<
Operating Speed: See Operating Speed section for complete speed specifications.
Connector Type: Screw terminal, #22 AWG wire size.
Isolation Between Any Two Terminals: >10
Isolation Between Any Terminal and Earth: >10
9
Ω
, <75pF.
9
Ω
, <150pF.
Common Mode Voltage: 350V peak between any terminal and earth.
Maximum Voltage Between Any Two Terminals: 200V peak.
Maximum Voltage Between Any Terminal and Model 200 1 Input LO: 200V peak.
ENVIRONMENTAL: Meets all Model 2001 environmental specifications.
DIMENSIONS, WEIGHT: 21mm high × 72mm wide × 221mm deep (0.83 in. ×
1.7 Unpacking and inspection ............................................................................................................................... 1-2
1.7.1Inspection for damage..............................................................................................................................1-2
1.8 Repacking for shipment ...................................................................................................................................1-2
3.2 Signal limitations ...............................................................................................................................................3-2
3.2.1Relay input signal limitations..................................................................................................................3-2
3.2.2Solid-state input signal limitations .........................................................................................................3-2
3.3.2Scanner option bus query.........................................................................................................................3-2
3.4 Front panel scanner controls............................................................................................................................3-2
3.4.1Open and close channels (CHAN)..........................................................................................................3-3
3.4.4Using SCAN to configure scan parameters...........................................................................................3-6
3.4.5Using EXIT to stop scanning....................................................................................................................3-7
3.5 IEEE-488 bus scanner commands....................................................................................................................3-7
3.6 Closing and opening channels.........................................................................................................................3-9
3.7.2IEEE-488 bus scanning............................................................................................................................3-10
3.8 Ratio and delta .................................................................................................................................................3-11
3.8.1Ratio and delta computation..................................................................................................................3-11
3.8.2Ratio and delta measurement functions...............................................................................................3-11
3.8.4Ratio and delta triggering ......................................................................................................................3-11
3.9 RTD temperature measurements ..................................................................................................................3-14
3.10 Using the scanner with the buffer.................................................................................................................3-15
4.4 Special handling of static-sensitive devices...................................................................................................4-9
4.5 Principles of operation....................................................................................................................................4-10
4.5.2Relay control ............................................................................................................................................ 4-10
5.2 Parts lists............................................................................................................................................................. 5-1
5.3 Ordering information ....................................................................................................................................... 5-1
5.4 Factory service ................................................................................................................................................... 5-1
5.5 Component layouts and schematic diagrams...............................................................................................5-1
iii
List of Illustrations
2Card Connections and Installation
Figure 2-1 Model 2001-SCAN simplified schematic ............................................................................................ 2-2
Figure 2-4 Routing wires through cable clamp..................................................................................................... 2-6
Figure 2-5 Connections for voltage scanning........................................................................................................ 2-7
Figure 2-6 Typical connections for 2-wire resistance scanning .......................................................................... 2-8
Figure 2-7 Typical connections for 4-wire resistance scanning .......................................................................... 2-9
Figure 2-8 Current shunt locations....................................................................................................................... 2-10
Figure 2-9 Current connections............................................................................................................................. 2-12
Figure 2-10 Typical connections for high-speed switching................................................................................. 2-13
Figure 3-8 Voltage attenuation by path isolation resistance............................................................................. 3-21
Figure 3-9 Power line ground loops ..................................................................................................................... 3-22
This section contains general information about the
Model 2001-SCAN scanner card option for the Model
2001 Multimeter. The Model 2001-SCAN provides 10
channels, including eight channels of 2-pole relay
switching, and two channels of 2-pole solid-state
switching. All channels can be conÞgured for 4-pole
operation.
Section 1 is arranged in the following manner:
1.2 Features
1.3 Warranty information
1.4 Manual addenda
1.5 Safety symbols and terms
1.6 SpeciÞcations
1.7 Unpacking and inspection
¥Eight channels of 2-pole relay input.
¥Two channels of 2-pole solid-state switching.
¥All channels conÞgurable for 4-pole operation.
¥Multiplex one of ten 2-pole, or one of Þve 4-pole
channels into the Model 2001 Multimeter.
¥Two-channel, high-speed multiplexing into Model
2001 Multimeter.
¥High-speed ratio and delta measurements.
1.3Warranty information
Warranty information is located on the inside front
cover of this instruction manual. Should your Model
2001-SCAN require warranty service, contact the
Keithley representative or authorized repair facility in
your area for further information. When returning the
scanner card for repair, be sure to Þll out and include
the service form at the back of this manual in order to
provide the repair facility with the necessary
information.
1.8 Repacking for shipment
1.2Features
The Model 2001-SCAN is scanner card designed to be
installed in the Model 2001 Multimeter. Key features
include:
1.4Manual addenda
Any improvements or changes concerning the scanner
card or manual will be explained in an addendum
included with the card. Addenda are provided in a
page replacement format. Simply replace the obsolete
pages with the new pages.
1-1
General Information
1.5Safety symbols and terms
The following symbols and terms may be found on an
instrument or used in this manual.
The symbol on an instrument indicates that the
user should refer to the operating instructions located
in the instruction manual.
The symbol on an instrument shows that high voltage may be present on the terminal(s). Use standard
safety precautions to avoid personal contact with these
voltages.
The WARNING heading used in this manual explains
dangers that might result in personal injury or death.
Always read the associated information very carefully
before performing the indicated procedure.
The CAUTION heading used in this manual explains
hazards that could damage the scanner card. Such
damage may invalidate the warranty.
!
and store it in the original packing carton. After
removing the card from its anti-static bag, inspect
it for any obvious signs of physical damage. Report
any such damage to the shipping agent
immediately.
1.7.3 Shipment contents
The following items are included with every Model
2001-SCAN order:
¥Model 2001-SCAN Scanner Card
¥Model 2001-SCAN Instruction Manual
¥CA-109 test lead set for output connections (two
red, two black)
¥Additional accessories as ordered
1.7.4 Instruction manual
1.6Specifications
Model 2001-SCAN speciÞcations are found at the front
of this manual. These speciÞcations are exclusive of the
Model 2001 Multimeter speciÞcations.
1.7Unpacking and inspection
1.7.1 Inspection for damage
The Model 2001-SCAN is packaged in a re-sealable,
anti-static bag to protect it from damage due to static
discharge and from contamination that could degrade
its performance. Before removing the card from the
bag, observe the precautions below on handling.
1.7.2 Handling precautions
¥Always grasp the card by the side edges and cov-
ers. Do not touch the board surfaces or components.
The Model 2001-SCAN Instruction Manual is threehole drilled so that it can be added to the three-ring
binder of the Model 2001 Multimeter Instruction Manual. After removing the plastic wrapping, place the
manual in the binder following the Model 2001 Instruction Manual.
If an additional Model 2001-SCAN Instruction Manual
is required, order the manual package, Keithley part
number 2001-SCAN-901-00. The manual package
includes an instruction manual and any pertinent
addenda.
1.8Repacking for shipment
Should it become necessary to return the Model 2001SCAN for repair, carefully pack the unit in its original
packing carton or the equivalent, and include the following information:
¥Advise as to the warranty status of the scanner
card.
¥Write ATTENTION REPAIR DEPARTMENT on
the shipping label.
¥When the card is not installed in a Model 2001
Multimeter, keep the card in the anti-static bag,
1-2
¥Fill out and include the service form located at the
back of this manual.
2
Card Connections and Installation
2.1Introduction
WARNING
The procedures in this section are intended only for qualiÞed service personnel. Do not perform these
procedures unless you are qualiÞed
to do so. Failure to recognize and observe normal safety precautions
could result in personal injury or
death.
This section includes information on making connections to the Model 2001-SCAN and on installing the
card in the Model 2001 Multimeter. This section is
arranged as follows:
2.2 Handling precautions: Explains precautions that
must be followed to prevent contamination to the
scanner card assembly. Contamination could
degrade the performance of the scanner card.
2.3 Connections: Covers the basics for connecting
external circuitry to the scanner card.
2.4 Typical connection schemes: Provides some
typical connection schemes for 2-pole and 4-pole
operation, and summarizes information on
installing current shunts and high-speed
multiplexing.
2.5 Card installation and removal: Summarizes the
procedure to install the scanner card in the Model
2001 Multimeter, outlines scanner card output
connections, and describes how to remove the
card.
2.2Handling precautions
To maintain high impedance isolation between channels, care should be taken when handling the scanner
card to avoid contamination from such foreign materials as body oils. Such contamination can substantially
lower leakage resistances, degrading card performance. To avoid possible contamination, always grasp
the scanner card by the side edges or covers. Do not
touch board surfaces, components, or areas adjacent to
electrical contacts.
Dirt build-up over a period of time is another possible
source of contamination. To avoid this problem, operate the multimeter and scanner card in a clean environment. If the card becomes contaminated, it should be
thoroughly cleaned as explained in paragraph 4.2.
2-1
Card Connections and Installation
2.3Connections
This paragraph provides the information necessary to
connect your external test circuitry to the scanner card.
WARNING
The following connection information is intended to be used by qualiÞed service personnel. Failure to
recognize and observe standard safety precautions could result in personal injury or death.
NOTE
All connecting wires or leads must be
connected to the card before it is installed in the Model 2001 Multimeter.
User-installed
current shunt
2.3.1 Card configuration
Figure 2-1 shows a simpliÞed schematic diagram of the
Model 2001-SCAN. The scanner card has ten input
channels and two outputs. Channels 1-4 and 6-9 are
switched by relays, while channels 5 and 10 are solidstate inputs. Channels 1 and 6 can be modiÞed for
current measurements by installing on-card shunt
resistors.
4-pole paired channels are as follows:
¥Channels 1 and 6
¥Channels 2 and 7
¥Channels 3 and 8
¥Channels 4 and 9
¥Channels 5 and 10
Channel 1
Channel 2-4
Channel 5
(Solid State)
User-installed
current shunt
Channel 6
Channel 7-9
Channel 10
(Solid State)
HI
LO
HI
LO
HI
LO
HI
LO
HI
OUT A (To Model 2001
input jacks)
LO
HI
OUT B (To Model 2001
sense jacks)
LO
2-Pole4-Pole
Figure 2-1
Model 2001-SCAN simplified schematic
2-2
Card Connections and Installation
2.3.2 Card connectors
Figure 2-2 shows the input/output connectors for the
card. Card connections include:
¥CH 1-10 (channels 1-10): HI and LO input termi-
nals are provided for each of the 10 channels on the
card.
NOTE
Channels 5 and 10 use solid-state
switching, while channels 1-4 and 6-9
use relay switching.
¥OUT A: HI and LO output connections for all ten
channels in the 2-pole mode or channels 1-5 in the
4-pole mode.
¥OUT B: HI and LO output connections for channels
6-10 in the 4-pole mode.
WARNING
Make sure all power is off and any
stored energy in external circuitry is
discharged before connecting or disconnecting wires.
CAUTION
Mechanical shock may open or close
latching relays on the scanner card.
Before enabling any external sources,
open all relays by inserting the
Model 2001-SCAN into the Model
2001 and turning on the power.
1. Open the plastic shield to gain access to the
connectors.
2. Strip approximately 5/16Ó of insulation from the
end of each wire, then twist the strands together.
NOTE
In order to gain access to the connections, Þrst open the
plastic shield by pressing in on the locking tab. Swing
the shield away from the circuit board.
2.3.3 Wiring procedure
Perform the following procedure to wire circuitry to
the screw terminals on the scanner card.
#22 AWG stranded wire is recommended for scanner card connections.
3. Loosen the screw terminal, then insert the wire
into the access hole.
4. While holding the wire in place, tighten the connector screw securely.
5. Repeat steps 1 through 3 for each wire to be connected.
6. Dress input wires through the cable clamp, as discussed in paragraph 2.3.5.
2-3
Card Connections and Installation
H L
CH 1
Channels 1-5, OUT AChannels 6-10, OUT B
H L
H L
H L
H L
CH 2
CH 3
CH 4
CH 5
H L
OUT A
H L
CH 6
H L
CH 7
H L
CH 8
H L
CH 9
H L
CH 10
H L
OUT B
Locking Tab
Plastic Shield
Figure 2-2
Card connectors
2.3.4 Output connections
Use the supplied test leads for scanner output connections. Connect red leads to the output (OUT A and
OUT B) HI terminals, and connect black leads to the
output LO terminals. See Figure 2-3 for details. Dress
output test leads through the cable clamp, as described
in paragraph 2.3.5. After all wires are connected and secure, close the plastic shield, and secure it with the
locking tab.
NOTE
If you intend to use the scanner card
only in the 2-pole mode, it is not necessary to connect output leads to both
OUT A and OUT B. Use only OUT A
for the 2-pole mode.
After the scanner card is installed, the output leads
must be connected to the multimeter rear panel input
jacks. See paragraph 2.5.2 for details.
2.3.5 Dressing leads
After wires are connected to the terminal blocks, they
should be dressed through the cable clamp as shown in
Figure 2-4. To do so, unlatch the clip that holds the
cable clamp together, then route all wires ßat against
the lower half of the clamp. Clamp the wires down,
then secure the clamp with the metal clip unlatched
earlier.
2-4
Card Connections and Installation
H L
CH 1
H L
CH 2
H L
CH 3
H L
CH 4
Red
H L
CH 5
H L
OUT A
HI
To 2001
Input
LO
Red
Black
H L
H L
H L
H L
H L
H L
CH 6
CH 7
CH 8
CH 9
CH 10
OUT B
Note: OUT B connections not required
for 2-pole operation. Plastic shield
not shown.
HI
LO
To 2001
Sense
Black
Figure 2-3
Output Connections
2-5
Card Connections and Installation
H L
CH 1
H L
CH 2
H L
CH 3
Metal Clip
H L
H L
CH 4
CH 5
H L
OUT A
H L
CH 6
H L
CH 7
H L
CH 8
H L
CH 9
H
CH 10
LHL
OUT B
Cable Clamp
Note : Plastic shield not shown.
Figure 2-4
Routing wires through cable clamp
2.4Typical connecting schemes
The following paragraphs discuss typical connections
for the scanner card.
2.4.1 Voltage connections
Figure 2-5 shows typical connections for voltage
measurements. Note that all channels are used in the 2pole mode, and that up to 10 voltage sources can be
switched with this conÞguration. This basic
conÞguration can be used for the following types of
measurements:
¥DCV
¥ACV
¥Frequency (voltage only)
All channels (1-10) can be used with this conÞguration.
2-6
Card Connections and Installation
CH 1
CH 2
CH 3
CH 4
CH 5
OUT A
CH 6
CH 7
CH 8
CH 9
CH 10
OUT B
H
L
H
L
H
L
H
L
H
L
H
L
HI
LO
To 2001
Input
HI
V
LO
HI
V
LO
HI
V
LO
HI
V
LO
HI
V
LO
Voltages
Under Test
H
L
H
L
H
L
H
L
H
L
H
L
HI
V
LO
HI
V
LO
HI
V
LO
HI
V
LO
HI
V
LO
2001-SCAN Card
Figure 2-5
Connections for voltage scanning
2-7
Card Connections and Installation
2.4.2 Resistance connections
2-Pole connections
(<275
Ω
) internal resistance of solid-
state channels.
Figure 2-6 shows typical 2-pole resistor test connections. The 2-pole resistance conÞguration can be used
to test up to eight DUTs.
NOTE
Channels 5 and 10 should not be used
to switch 2-wire resistance measurements because of the relatively high
H
CH 1
L
H
CH 2
L
H
CH 3
L
H
CH 4
L
H
CH 5
L
H
OUT A
L
4-Pole connections
Typical 4-pole resistance connections are shown in Figure 2-7. This general conÞguration can be used with all
channels to scan:
¥4-wire resistance measurements.
¥4-wire RTD temperature measurements.
Resistors
Under Test
HI
To 2001
LO
Input
H
CH 6
L
H
CH 7
L
H
CH 8
L
H
CH 9
L
H
CH 10
L
H
OUT B
L
2001-SCAN Card
Figure 2-6
Typical connections for 2-wire resistance scanning
2-8
Resistors
Under Test
CH 1
CH 2
CH 3
CH 4
CH 5
OUT A
CH 6
CH 7
CH 8
CH 9
CH 10
OUT B
Card Connections and Installation
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
LO
To 2001 Sense
HI
Resistors
Under Test
2001-SCAN Card
Figure 2-7
Typical connections for 4-wire resistance scanning
LO
HI
To 2001 Input
2-9
Card Connections and Installation
2.4.3 Current measurements
Current shunts can be installed on the circuit board to
allow indirect AC and DC current measurements to be
made through channels 1 and 6 only. The following
paragraphs discuss installing current shunts and the
basic methods used to determine currents.
CAUTION
Board mounted current shunt resistors can be installed only for chan-
R145 (Channel 1 shunt)R146 (Channel 6 shunt)
H L
H L
H L
H L
H L
H L
CH 1
CH 2
CH 3
CH 4
CH 5
OUT A
nels 1 and 6. A channel that has been
modiÞed with a current shunt resistor should not be used for voltage or
resistance measurements.
Current shunt locations
Figure 2-8 shows the locations for the user-installable
current shunts. Location R145 is for channel 1 and R146
is for channel 6.
H L
H L
H L
H L
H L
H L
CH 6
CH 7
CH 8
CH 9
CH 10
OUT B
Figure 2-8
Current shunt locations
2-10
I
V
R
--- -=
Card Connections and Installation
Recommended current shunt values
Hole spacing on the circuit board is intended for 1/4W
resistors. The resistance value will depend on the current you intend to measure; 1k
optimum for many applications. A 1k
allow you to switch currents up to 15mA without
exceeding the power rating of the resistor.
For larger currents, decrease the shunt value. Conversely, the shunt value can be increased for smaller
currents.
Ω
resistors should be
Ω
resistor will
Board cleaning
CAUTION
Failure to observe the following precautions may result in degraded card
performance.
Current measurements
Even with the current shunts installed, you cannot
make direct current measurements with the scanner
card. Instead, you must close the channel to be measured, and measure the voltage across the shunt. The
current can then be calculated as follows:
Where:I = current being determined
V = voltage measured by Model 2001
R = shunt resistance value
Instead of manually calculating current, set up a Model
2001 mx + b math calculation function. (Here, m = 1/R
and b = 0.). The Model 2001 will then display the actual
current value. Refer to the Model 2001 OperatorÕs
Manual for details on using math functions.
When soldering resistors, be sure not to touch areas not
associated with resistor installation or spread ßux
around to other areas of the circuit board. Use solder
with an OA (organic activated) ßux. The circuit board
should be thoroughly cleaned with pure water after
soldering to remove all contaminants. After cleaning
with water, swab the area with pure methanol, then allow the board to dry for several hours in a 50¡C environment before use.
Current connections
Figure 2-9 shows typical connections for measuring
currents using the Model 2001-SCAN with current
shunts installed. As noted previously, only channels 1
and 6 have current shunts installed, and this conÞguration can be used to scan the following:
¥DC current
¥AC current
2-11
Card Connections and Installation
CH 1
CH 2
CH 3
CH 4
CH 5
OUT A
CH 6
CH 7
CH 8
CH 9
CH 10
OUT B
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
H
L
Note: Current shunts must be
installed for channels
1 and 6.
AC or DC
A
To 2001
Input
AC or DC
A
Current
Current
Figure 2-9
Current connections
2-12
2001-SCAN Card
Card Connections and Installation
2.4.4 High-speed multiplexer and ratio/delta
connections
If you intend to use the high-speed multiplexer or
ratio/delta features of the Model 2001, you must connect the two input sources to channels d 10. These two
channels use solid-state switching and are the only
H
CH 1
L
H
CH 2
L
H
CH 3
L
H
CH 4
L
H
CH 5
L
H
OUT A
L
channels that can be used for high-speed switching.
Output signals should be taken from OUT A.
Figure 2-10 shows connections for high-speed switching. Note that only 2-pole switching is available for this
operating mode.
V
H
CH 6
L
H
CH 7
L
H
CH 8
L
H
CH 9
L
H
CH 10
OUT B
L
H
L
2001-SCAN Card
Figure 2-10
Typical connections for high-speed switching
To 2001
Input
Note: Only Channels 5 and 10
can be used for high-speed
switching.
V
2-13
Card Connections and Installation
2.5Card installation and removal
This paragraph explains how to install and remove the
Model 2001-SCAN card assembly from the Model 2001
Multimeter.
WARNING
Installation or removal of the Model
2001-SCAN should be performed
only by qualiÞed service personnel.
Failure to recognize and observe
standard safety precautions could
result in personal injury or death.
CAUTION
To prevent contamination to the
scanner card that could degrade performance, handle the card assembly
only by the card edges and covers.
NOTE
Wiring connections must made before
installing the scanner card. See paragraph 2.4 for wiring details.
2.5.1 Scanner Card Installation
Perform the following steps and refer to Figure 2-11 to
install the card assembly in the Model 2001
Multimeter:
WARNING
Turn off power to all instrumentation
(including the Model 2001 Multimeter) and disconnect all line cords.
Make sure all power is removed and
any stored energy in external circuitry is discharged.
1. Remove the cover plate from the SCANNER slot
on the rear panel of the Model 2001 Multimeter. To
do so, pry out the two fasteners, then remove the
cover plate.
2. Slide the card edges into the guide rails inside the
multimeter (solder side up).
3. With the ejector arms in the unlocked position,
carefully push the card all the way forward until
the arms engage the ejector clips. Push both arms
inward to lock the card into the multimeter.
4. After installation, connect the output leads to the
multimeter as discussed below.
2-14
Unlock card
Ejector Arms (2)
Card Connections and Installation
Figure 2-11
Card installation
Lock card
2-15
Card Connections and Installation
2.5.2 Output connections to multimeter
After installation, connect the scanner card output
leads to the Model 2001 rear panel jacks as follows:
¥For 2-pole operation, connect OUT A HI (red) to
INPUT HI, and connect OUT A LO (black) to
INPUT LO. See Figure 2-12.
¥For 4-pole operation, connect OUT A HI (red) to
INPUT HI, and connect OUT A LO (black) to
INPUT LO. Also connect OUT B HI (red) to SENSE
HI, and connect OUT B LO (black) to SENSE LO.
See Figure 2-13.
NOTE
Be sure to select the rear inputs with
the Model 2001 front panel INPUTS
switch when using the scanner.
Input HI
2.5.3 Scanner card removal
Follow the steps below to remove the scanner card
from the multimeter:
WARNING
Turn off power to all instrumentation
(including the Model 2001 Multimeter) and disconnect all line cords.
Make sure all power is removed and
any stored energy in external circuitry is discharged.
1. Unlock the card by pulling the latches outward.
2. Carefully slide the card out of the multimeter.
3. If the multimeter is to be operated without the
scanner card installed, install the cover plate over
the SCANNER slot.
Out A
HI (Red)
Figure 2-12
2-pole output connections
Input LO
Out A
LO (Black)
2-16
Sense HI
Out A
HI (Red)
Out B
HI (Red)
Input HI
Sense LO
Input LO
Card Connections and Installation
Figure 2-13
4-pole output connections
Out B
LO (Black)
Out A
LO (Black)
2-17
3
Operation
3.1Introduction
This section contains detailed information on front
panel and IEEE-488 bus operation of the Model 2001SCAN. The information in this section is organized as
follows:
3.2 Signal limitations: Summarizes the maximum
signals that can be applied to the Model 2001SCAN.
3.3 Scanner card detection: Discusses how the scan-
ner card is detected and how to determine whether or not the card is installed with a bus command.
3.4 Front panel scanner controls: Gives an overview
of the Model 2001 Multimeter front panel controls
used to control the scanner card.
3.5 IEEE-488 bus scanner commands: Summarizes
bus commands necessary to control the scanner
card.
3.6 Opening and closing channels: Covers the basic
methods for closing and opening channels.
3.7 Scanning channels: Details how to conÞgure scan
parameters and how to perform scanning.
3.8 Ratio and delta: Describes how to conÞgure the
instrument for ratio and delta operation.
3.9 RTD temperature measurements: Provides
detailed information on using RTD probes when
scanning.
3.10 Using the buffer with the scanner: Provides
detailed instructions for using the Model 2001
internal data buffer to store readings taken using
the scanner.
ber of measurement considerations that should be
taken into account when using the scanner.
NOTE
Before using the Model 2001-SCAN
scanner card, you should be thoroughly familiar with the operation of
the Model 2001 Multimeter. See the
Model 2001 OperatorÕs Manual for
details.
3-1
Operation
3.2Signal limitations
CAUTION
To prevent damage to the Model
2001-SCAN, do not exceed the maximum signal level speciÞcations of
the card.
3.2.1Relay input signal limitations
Channels 1-4 and 6-9 are the relay inputs. To prevent
over-heating or damage to the relays, never exceed the
following maximum signal levels for these channels:
DC signals: 110V DC, 1A switched, 30VA (resistive
load).
AC signals: 125V rms or 175V AC peak, 1A switched,
62.5VA (resistive load).
3.2.2Solid-state input signal limitations
Channels 5 and 10 are solid-state inputs. To prevent
damage, never exceed the following maximum signal
levels for these channels:
If the card is not present at power-on, scanner bus commands or queries will generate a ÒMissing hardware
errorÓ, and front panel operations pertaining to the
scanner will inform you that no scanner is present.
3.3.2Scanner option bus query
*OPT? is an IEEE 488.2 common query which will
allow you determine whether or not the Model 2001SCAN card is installed. The response to this query has
two Þelds. The Þrst Þeld identiÞes the presence or
absence of expansion memory, and the second Þeld
indicates whether or not the scanner is present as
follows:
¥0: Scanner not installed.
¥2001-SCAN: Scanner installed.
Refer to paragraph 4.9 of the Model 2001 OperatorÕs
manual for more details on using the *OPT? query.
Maximum signal level: 110V DC, 175V peak AC, 50mA.
3.3Scanner card detection
3.3.1Power-up detection
The scanner card is detected only at power-on. If the
card is plugged into the Model 2001 after the power is
turned on, the card will not be recognized as being
present by the Model 2001.
CAUTION
Plugging in the scanner card with
power turned on may result in damage to both the Model 2001-SCAN
and the Model 2001 Multimeter.
3.4Front panel scanner controls
The following paragraphs give an overview of the various Model 2001 Multimeter controls used with the
scanner. Figure 3-1 shows the front panel of the Model
2001. Controls that affect Model 2001-SCAN operation
include:
¥CHAN: Allows you to open and close channels
directly.
¥CONFIG-CHAN: DeÞnes the measurement func-
tions for each scanner channel.
¥CONFIG-SCAN: Selects internal/external scan
list, and controls ratio/delta operation.
¥SCAN: Enters scan conÞguration menu.
¥ and : Manually scans through channels.
3-2
Operation
ERR REM TALK LSTN SRQ REAR REL FILT MATH 4W AUTOARM TRIG SMPL
PREV
DISPLAY
NEXT
POWER
DCVACVDCIACIΩ2Ω4
REL TRIG
INFO LOCALEXIT ENTER
CHAN
• Close channel
• Open channel
CONFIG-CHAN
• Define internal channel functions
• Define external channel functions
• Define alternate function
STORE RECALL
CHAN SCAN
FILTER MATH
CONFIG MENU
SCAN
• Scan configuration
CONFIG-SCAN
• Select internal scan list
• Select external scan list
• Enable ratio/delta
2001 MULTIMETER
FREQTEMP
SENSE
Ω 4 WIRE
HI
RANGE
AUTO
RANGE
350V
PEAK
FR
!
LO
INPUTS
FRONT/REAR
CAL
• Manually scan channels
EXIT
• Disable scanning
INPUT
2A 250V
AMPS
1100V
PEAK
500V
PEAK
Figure 3-1
Model 2001 front panel scanner controls
3.4.1Open and close channels (CHAN)
The CHAN key allows you directly:
¥Open any closed channel(s) immediately.
¥Close a speciÞc channel (or channel pair for 4-wire
functions).
Pressing CHAN will display the following menu
choices:
CHANNEL SELECTION
CLOSE-CHANNELOPEN-ALL-CHANNELS
OPEN-ALL-CHANNELS
Selecting OPEN-ALL-CHANNELS will immediately
open any closed scanner card channel(s).
CLOSE-CHANNELS
Selecting CLOSE-CHANNEL will display the following message prompting you to select the channel to
close:
ENTER CHAN#00 (1-10)
The Þeld entry after ÒENTER CHAN#Ó indicates the
channel to close. Ò00Ó will be displayed if all channels
3-3
Operation
are open. (Pressing ENTER with Ò00Ó displayed will
display a message that no channel has been closed.) To
close a channel, simply use the cursor and range keys
to select the number of the channel to close, then press
ENTER. The number of the closed channel will be displayed on the front panel along with normal readings.
Selecting a different channel from the one that is presently closed will cause the closed channel to open and
allow a settling time before closing the selected channel. Note that you cannot select channel 00 to open
channels; instead you must use the OPEN-ALLCHANNELS selection in the menu.
Channel relays will be closed according to the presently selected function. If a 2-wire function is used, only
the relay for that one channel will be closed. If a 4-wire
function is selected, both the selected channel relay and
the matching relay pair will close. For example, closing
channel 2 will also close the channel 7 relay. Fixed 4pole relay pairs are:
¥1 and 6
¥2 and 7
¥3 and 8
¥4 and 8
INTERNAL-CHANS
The INTERNAL-CHANS selection allows you to set
the measuring function for each of the Model 2001SCAN channels. When this selection is made, the following submenu will be displayed:
SET INTERNAL CHANS
1=DCV2=DCV3=DCV4=DCV5=DCV
6=DCV7=DCV8=DCV9=DCV10=DCV
With this menu displayed, use the cursor keys to select
the channel, and use the up arrow and down arrow
(range) keys to select the desired measuring function
for each channel:
DCV: DC volts
ACV: AC volts
Ω
2W: 2-wire ohms
Ω
4W: 4-wire ohms
FRQ: frequency
TMP: temperature
ALT: alternate function (see below)
¥5 and 10.
3.4.2Configure channels (CONFIG-CHAN)
CONFIG-CHAN allows you to:
¥Select measurement functions for internal (Model
2001-SCAN) channels.
¥Select measurement functions for channels in an
external scanner used with the Model 2001.
¥DeÞne an alternate measurement function which
can then be assigned to speciÞc channels.
Pressing CONFIG then CHAN will display the following menu:
CONFIGURE CHANNELS
INTERNAL-CHANSEXTERNAL-INPUTS
SAVE-ALT-FCNRESTORE-ALT-FCN
--- : None
Ω
4W function: The
channels 1-5. If selected, ÒPRDÓ (paired) will be shown
on the corresponding paired channel 6-10. Once
is selected on channels 1 to 5, changing the assignment
to a different function will de-assign the paired channel
and change the function to Ò---Ó (none).
TMP function: Similarly, the TMP selection is valid
only for channels 1-5 if the temperature sensor is a 4wire RTD type. If a 2-wire RTD type is used, channels
6-10 could be assigned to the TMP function, but if the
sensor type is later change to 4- wire RTD, any channel
from 6-10 will then be set to Ò---Ó (none).
No function (---): Selecting none (---) effectively removes that channel from the scan list. When scanning,
the instrument will skip any channels that have no
function deÞned.
Ω
4W function is valid only for
Ω
4W
3-4
Operation
EXTERNAL-INPUTS
This menu item allows you to select measurement
functions for an external scanner used with the Model
2001 Multimeter. When the EXTERNAL-INPUTS
menu item is selected, the instrument will prompt you
to enter the number of channels being used:
# EXTERNAL INPUTS=00
Use the cursor and range keys to select the number of
channels (1-80), then press ENTER. Once the number
of inputs is selected, you will be prompted for channel
functions:
SET CHAN FUNCTIONS
DEFAULTCHOOSE-FUNCTIONS
Brießy, these menu items allow you to select the
following:
DEFAULT:
measurement function to all external channels.
This selection assigns the presently selected
You can also use the ALT function to store an existing
main function but with a different set of operating
parameters. For example, you could set up a speciÞc
set of operating parameters for the straight DCV function and a second DCV setup as the ALT function. This
arrangement allows you to specify changes in virtually
any measurement parameter from channel to channel
even if the measurement functions are the same.
SAVE-ALT:
all its conÞgured settings as the ALT function.
RESTORE-ALT:
the ALT function and all associated settings as if a normal function change were taking place.
Stores the presently selected function and
Restores the function that was saved as
3.4.3Scan configuration (CONFIG-SCAN)
CONFIG-SCAN allows you to conÞgure the following
scanner aspects:
¥Select the internal or external channel list for
scanning.
CHOOSE-FUNCTION:
deÞne functions for each channel through the following prompt:
This menu choice allows you to
SELECT CHAN= 01 (DCV)
Here, the parameter in parenthesis deÞnes the presently selected function: DCV, ACV, ACI, DCI,
FRQ, TMP, ALT, JN1...JN5. As with other menu choices,
use the range and cursor keys to select channels and
functions. Note that current functions (DCI, ACI) are
allowed for external, but not internal scan list.
Ω
2W,
Ω
4W,
SAVE-ALT-FCN/STORE-ALT-FCN
An ALT (alternate) function is one that cannot be
directly accessed with one of the eight function keys.
For example, assume that you select the ACV peak
function using CONFIG-ACV. You can then use SAVEALT to assign peak ACV to the ALT function. Whenever the ALT function is encountered in the scan list,
the instrument will switch to the ACV peak function
for that channel even if the instrument is measuring a
different type of ACV (RMS for example).
¥Enable ratio and delta operation.
Pressing CONFIG-SCAN will display the following
menu:
SCAN OPERATION
INTERNALEXTERNALRATIODELTA
These choices select the action the instrument will take
when it is triggered.
INTERNAL
This selection enables scanning with the internal
Model 2001- SCAN scanner card. When this selection is
chosen, the Model 2001 will change to the function
speciÞed for the Þrst channel and then close the channel and take a reading. When the next trigger is
received, the instrument will open the present channel,
change to the speciÞed measuring function for the next
channel, and then close the relay and take a reading.
The process repeats until all channels in the list are
scanned.
3-5
Operation
EXTERNAL
This menu selection enables scanning with an external
scanner card located in a switching mainframe. This
selection operates in a manner similar to the INTERNAL except that the internal scanner card is not used.
When this menu item is selected, the instrument will
immediately change to the selected measuring function for the Þrst channel. When the multimeter is triggered, it will take a measurement and then change to
the measurement function for the next channel. This
process repeats until all channels in the scan list are
scanned.
RATIO/DELTA
Either of these two selections will conÞgure the Model
2001 to measure the two speciÞed channels and then
compute the ratio or difference (delta) between them.
When RATIO or DELTA is selected, and the instrument
is appropriately triggered, the measure relay will be
closed. A reading will be taken, then the reference relay
will be closed, and a second reading will be taken. The
reference relay will then be opened, and the ratio or
delta computation will be performed and displayed
using the two measured values.
Again, use the cursor keys to select the channel to be
used as the ratio reference channel.
The FUNCTION menu appears as follows:
SET RATIO FUNCTION
DCV
Ω
2
Ω
4
Use the cursor keys to select the desired function: DCvolts, ohms (2-wire), or 4-wire ohms.
Selections for DELTA measure and reference channels,
and function are essentially the same except, of course,
that you would select DELTA under the SCAN OPERATION menu.
Solid-state switching considerations
The solid-state relays on the scanner card are used for
switching only under the following circumstances:
¥Scan operation is set to USE INTERNAL LIST, and,
RATIO/DELTA channel selection
To select channels for RATIO and DELTA, select
RATIO or DELTA as appropriate.
Selecting RATIO will display the following menu and
allow you to set the measure or reference channel:
CONFIGURE RATIO
MEASUREREFERENCEFUNCTION
Selecting MEASURE will display the following:
RATIO MEASURE CHAN
CH12345678910
Use the cursor keys to select the measure channel.
Similarly, selecting REFERENCE will display:
¥Only internal channels 5 and 10 are selected, and,
¥The measurement functions for channels 5 and 10
are the same.
Under any other circumstances, latching relays will be
used for signal switching. (Solid state relays and
mechanical relays for channels 5 and 10 are in series.)
3.4.4Using SCAN to configure scan
parameters
Once the internal or external scan list is enabled, you
use the SCAN key to conÞgure scan count, scan interval, and enable buffer storage. The steps below outline
the basic procedure for using the SCAN key to conÞgure internal scanner operation.
1. From normal display, press CONFIG-SCAN. The
instrument will display the following:
RATIO REFERENCE CHAN
CH12345678910
3-6
SCAN OPERATION
INTERNALEXTERNALRATIODELTA
Operation
2. Select INTERNAL, then press ENTER.
3. Press SCAN. The unit will display the following
message:
SCAN COUNT = 00010
4. Using the range and cursor keys, select the number
of scan sequences, then press ENTER. The instrument will display the following:
USE SCAN TIMER?
YESNO
5. If you do not wish to use the scan timer (interval
between scans), select NO, then press ENTER, and
go on to step 7. If you wish to use and program the
interval between scans, select YES, then press
ENTER. The instrument will display the following:
INTRVL = 000002.500
6. Using the range and cursor keys, select the desired
interval between scan sequences, then press ENTER.
7. The instrument will then prompt you as to whether or not you wish to store data in the buffer as follows:
Press ENTER to begin
0010 scans of 10 channels
11. The instrument will then scan using selected scanning parameters. If you elected to store data in
memory, the instrument will display the reading
number on the bottom line of the display as readings are stored.
12. After readings are stored, the following will be displayed:
SCAN COMPLETE
RECALL-DATASCAN-AGAINEXIT
13. Select the desired operation, then pressENTER.
3.4.5Using EXIT to stop scanning
To temporarily halt triggering of ratio/delta measurements, simply press the EXIT key. You can then press
SCAN to restart the process.
To disable scanning, press the EXIT key.
DATA TO MEMORY?
NOYES
8. To store scanned data in the buffer, select YES; otherwise choose NO, then press ENTER.
9. If you elected to store data in memory, the instrument will prompt you as follows:
00100 RDGS TO BUFFER
Press ENTER to continue.
NOTE
Use CONFIG-STORE to program the
number of readings to store.
10. Press ENTER to begin scanning at the following
prompt:
3.4.6Manual scanning
The and keys can be used to manually scan
through channels. In order to use this feature, Þrst close
a channel using the CHAN key. Use to increment
channels, or use to decrement channels.
3.5IEEE-488 bus scanner commands
Table 3-1 summarizes commands that control scanner
operations over the IEEE-488 bus. For more detailed information on these and other bus commands, refer to
Section 4 of the Model 2001 Multimeter OperatorÕs
Manual.
:FUNCtion <function>
:LSELect INTernal | EXTernal | RATio |
DELTa | NONE
[:SENSe[1]]
:ALTernate[1]
: S AVe
:RECall
Route subsystem.
Close channels.
Return all closed channels.
Open channels.
Open any closed channels.
Scanning commands.
Program internal scan list.
Program channel functions.
Program external scan list.
Program ratio mode.
Select reference channel.
Select measurement channel
Select ratio function
Program delta mode.
Select reference channel.
Select measurement channel.
Select delta function.
Select scan list.
Sense subsystem
Program alternate function.
Save alternate function.
Recall alternate function.
The INT or EXT <function> parameter is one of the following:
VOLTage: DC
VOLTage:AC
TEMPerature
FREQuency
RESistance
FRESistance
RJUNctionX
NONE
ALTernate[1]
DC volts
AC volts
Temperature
Frequency
2-wire resistance
4-wire resistance
Reference junction (X=1 to 5)
No function (skips listed channel during scan.)
Alternate function
The RATio or DELTa <function> parameter is one of
the following:
VOLTage:DC
RESistance
FRESistance
NOTES:
1.The :ROUT:SCAN:LSEL command is coupled to the :ROUT:SCAN:INT command. When the :ROUT:SCAN:INT command is executed,
the :ROUT:SCAN:LSEL parameter will be set to INTernal.
2.Upper-case letters indicate short form of commands.
3.Brackets indicate optional command and should not be used when sending commands to instrument.
DC volts
2-wire resistance
4-wire resistance
3-8
Operation
3.6Closing and opening channels
Individual scanner card channels are closed and
opened using the CHAN key. The following paragraphs discuss closing and opening channels from the
front panel as well as with bus commands.
3.6.1Closing channels
Front panel
Use the front panel CHAN key to close speciÞc channels as follows:
14. From normal display, press the CHAN key. The
instrument will display the following menu:
CHANNEL SELECTION
CLOSE-CHANNELOPEN-ALL-CHANNELS
3.6.2Opening channels
Front panel
Use the front panel CHAN key to open any closed
channels as follows:
1. Press the CHAN key. The instrument will display
the following menu:
CHANNEL SELECTION
CLOSE-CHANNELOPEN-ALL-CHANNELS
2. Select OPEN-ALL-CHANNELS, then press
ENTER. The closed channel will open
immediately.
IEEE-488 bus
Use the :ROUT:OPEN command to open the closed
channel. For example, the following command would
be used to open channel 3:
OUTPUT 716; Ò:rout:open (@3)Ó
15. Select CLOSE-CHANNEL, then press ENTER. The
Model 2001 will display the following prompt:
ENTER CHANNEL# 00 (1-10)
16. Use the cursor and range keys to select the channel
you wish to close (1-10), then press ENTER. Any
previously closed channel will open, and the
selected channel will close.
NOTE
Once a channel is closed, use the or
key to manually scan through
channels. Also, you can use the NEXT
display to view three successive channels simultaneously.
IEEE-488 bus
Use the :ROUT:CLOSE command to close the desired
channel. For example, assume you wish to close channel 3. The following command would be used:
(You can also use :ROUT:OPEN:ALL or :ROUT:OPEN
ALL to open channels.)
3.7Scanning channels
Scanner channels are scanned by conÞguring scan
channels and programming the Model 2001 to perform
a scan. The following paragraphs outline step-by-step
procedures for performing basic scanning from the
front panel and over the IEEE-488 bus.
3.7.1Front panel scanning
Step 1: Configure channels
Use CONFIG-CHAN to select the measurement functions for each of the scanner channels as follows:
1. Press CONFIG-CHAN. The instrument will display the following menu:
CONFIGURE CHANNELS
INTERNAL-CHANSEXTERNAL-INPUTS
OUTPUT 716; Ò:rout:close (@3)Ó
2. Select INTERNAL-CHANS, then press ENTER.
The multimeter will display the following menu:
3-9
Operation
SET INTERNAL CHANS
1=DCV2=DCV3=DCV4=DCV5=DCV
3. Using the cursor keys, select the desired channel
(press the right cursor key to display channels 6
through 10).
4. Using the range keys, select the desired measure-
ment function: DCV, ACV, Ω2W, Ω4W, FRQ, TMP,
ALT, --- (None)
5. Repeat steps 3 and 4 for each of the channels you
wish to scan. NOTE: Select --- (none) to omit a
channel from the scan list.
6. After selecting all measurement functions, press
ENTER.
7. Press EXIT to return to normal display.
Step 2: Configure and start scan
ConÞgure the scan as follows:
1. Press CONFIG-SCAN. The Model 2001 will display the following:
SCAN OPERATION
INTERNALEXTERNALRATIODELTA
2. Select INTERNAL, then press ENTER.
3. Press SCAN, and follow the prompts to conÞgure
scanning. See paragraph 3.4.4 for details.
3.7.2IEEE-488 bus scanning
Step 1: Program channel functions
Use :ROUT:SCAN:INT:FUNC to program functions for
the selected channels. For example, assume that you
want to measure DC volts on channel 1, AC volts on
channel 3, and 2-wire resistance on channel 5. The commands to do so are as follows:
OUTPUT 716; Ò:rout:scan:int:func (@1),Õvolt:dcÕÓ
OUTPUT 716; Ò:rout:scan:int:func (@3),Õvolt:acÕÓ
OUTPUT 716; Ò:rout:scan:int:func (@5),ÕresÕÓ
If, on the other hand, you wish to use the same function
(DCV, for example) on all three channels, a single command would sufÞce:
Use the :ROUT:SCAN:INT command to program a
scan list (channels you wish to scan). For example, assume that you wish to scan channels 1, 3, and 5. This
scan list would be programmed as follows:
OUTPUT 716; Ò:rout:scan:int (@ 1,3,5)Ó
Scanning will begin immediately when this command
is sent.
To disable scanning, send the :ROUT:SCAN:LSEL
NONE command:
OUTPUT 716; Ò:rout:scan:lsel noneÓ
NOTE
The :ABORT command will abort the
present scan in progress and reset the
channel list to the beginning. Depending on various trigger layer parameters, :ABORT may also stop the
scanning process.
3.8.2Ratio and delta measurement
functions
The following measurement functions are available in
the ratio and delta modes:
¥DC volts
¥2-wire ohms
¥4-wire ohms
3.8.3Solid-state switching
Channels 5 and 10 on the scanner card have solid-state
inputs. Solid state switching is used only if all of the
following conditions are satisÞed:
¥Channels 5 and 10 are deÞned as the measurement
and reference channels.
¥The internal scan list is enabled.
¥Both channels 5 and 10 use the same measurement
function.
3.8Ratio and delta
The Model 2001 can display the difference (DELTA) or
quotient (RATIO) between the signal on any two scanner channels. The following paragraphs discuss ratio
and delta calculations and also give step-by-step procedures for using ratio and delta.
3.8.1Ratio and delta computation
During conÞguration, one channel is deÞned as the reference channel, and a second channel is deÞned as the
measurement channel. Ratio and delta are computed
from signals measured on these channels as follows:
Ratio
DeltaMeasurement Reference–=
Measurement
------------------------------------=
Reference
3.8.4Ratio and delta triggering
When the instrument is Þrst placed in the ratio or delta
mode, it will close the scanner reference channel and
then wait for a trigger. When the reading is triggered,
the unit will make a measurement on the reference
channel, switch to the measurement channel, and then
take a second measurement. After measuring the measurement channel, the unit will compute and display
the ratio or delta value, and switch back to the reference channel to wait for the next trigger.
3.8.5Ratio operation
Ratio display formatting
All ratio measurements are displayed using 4-½ digit
scientiÞc notation format. This format allows the widest possible dynamic range, although at the expense of
some small loss in resolution. Note that no sufÞxes
such as mV are used since ratio readings. The function
(for example VDC) is displayed only to indicate the
selected measurement function.
3-11
Operation
Because of the scientiÞc notation format, the
ADVANCED Þlter cannot be used with the ratio mode.
The advanced Þlter uses a noise-tolerance window that
is expressed in terms of display counts, which do not
apply to scientiÞc notation display. An appropriate
warning message will be displayed if you attempt to
enable the ratio mode and advanced Þlter
simultaneously.
Front panel ratio operation
Step 1: Connect inputs
Input signals must be connected to the two channels
you intend to deÞne as measurement and reference
channels.
Step 2: Define measurement channel
1. From normal display, press CONFIG-SCAN. The
instrument will display the following:
SCAN OPERATION
INTERNALEXTERNALRATIODELTA
2. Select RATIO, then press ENTER. The Model 2001
will display the following:
CONFIGURE RATIO
MEASUREREFERENCEFUNCTION
3. Select MEASURE, then press ENTER. The instrument will display the following:
RATIO MEASURE CHAN
CH12345678910
4. Using the cursor keys, select the channel you wish
to deÞne as the measure channel, then press
ENTER.
Step 3: Define reference channel
Step 4: Select measurement function
1. From the CONFIGURE RATIO menu, select
FUNCTION, then press ENTER. The instrument
will display the following:
SET RATIO FUNCTION
DCVΩ 2Ω4
Note that only DC volts, and 2- and 4-wire ohms
functions are available for ratio mode.
2. Use the cursor keys to select the desired function,
then press ENTER.
3. Press EXIT to return to normal display.
Step 5: Display ratio readings
Once the reference channel, measurement channel, and
ratio function have been deÞned, press SCAN to halt
triggers. Then press SCAN to start ratio measurements.
The instrument will automatically display ratio readings computed from signals applied to the reference
and measurement channels. If you have a selected trigger mode that requires a separate trigger for each reading, you will, of course, have to trigger the instrument
to obtain each ratio reading (refer to the Model 2001
OperatorÕs Manual for details on triggering).
Canceling the ratio mode
Press SCAN to temporarily halt the ratio mode. To disable scanning, press EXIT.
IEEE-488 bus ratio operation
Step 1: Connect inputs
Input signals must be connected to the two channels
you intend to deÞne as measurement and reference
channels.
1. From the CONFIGURE RATIO menu, select REFERENCE, then press ENTER. The Model 2001 will
display the following message:
RATIO REFERENCE CHAN
CH12345678910
2. Using the cursor keys, select the channel to be deÞned as the reference channel, then press ENTER.
3-12
Step 2: Define measurement channel
Use the :ROUT:SCAN:RAT:MCH command to deÞne
the measurement channel. For example, assume you
wish to deÞne channel 10 as the measurement channel.
The following command would be used:
OUTPUT 716; Ò:rout:scan:rat:mch (@10)Ó
Operation
Step 3: Define reference channel
Use :ROUT:SCAN:RAT:RCH to deÞne the reference
channel. The following command would be used to
deÞne channel 5 as the reference channel:
OUTPUT 716; Ò:rout:scan:rat:rch (@5)Ó
Step 4: Select measurement function
Send the :ROUT:SCAN:RAT:FUNC command to select
the ratio measurement function. For example, to select
DCV, send the following:
OUTPUT 716; Ò:rout:scan:rat:func Ôvolt:dcÕÓ
Step 5: Enable ratio mode
Send the :ROUT:SCAN:LSEL RAT command to enable
the ratio mode:
OUTPUT 716; Ò:rout:scan:lsel ratÓ
Step 2: Define measurement channel
1. From normal display, press CONFIG-SCAN. The
instrument will display the following:
SCAN OPERATION
INTERNALEXTERNALRATIODELTA
2. Select DELTA, then press ENTER. The Model 2001
will display the following:
CONFIGURE DELTA
MEASUREREFERENCEFUNCTION
3. Select MEASURE, then press ENTER. The instrument will display the following:
DELTA MEASURE CHAN
CH12345678910
4. Using the cursor keys, select the channel you wish
to deÞne as the measure channel, then press
ENTER.
Step 6: Request ratio readings
Once the reference channel, measurement channel, and
ratio function have been deÞned, use the DATA? query
to request readings. The following code fragment demonstrates the process:
To cancel the ratio mode, send the :ROUT:SCAN:LSEL
NONE command as follows:
OUTPUT 716; Ò:rout:scan:lsel noneÓ
3.8.6Delta operation
Front panel delta operation
Step 1: Connect inputs
Step 3: Define reference channel
1. From the CONFIGURE DELTA menu, select REFERENCE, then press ENTER. The Model 2001 will
display the following message:
DELTA REFERENCE CHAN
CH12345678910
2. Using the cursor keys, select the channel to be deÞned as the reference channel, then press ENTER.
Step 4: Select measurement function
1. From the CONFIGURE DELTA menu, select
FUNCTION, then press ENTER. The instrument
will display the following:
SET DELTA FUNCTION
DCVΩ 2Ω4
Note that only DC volts, and 2- and 4-wire ohms
functions are available for delta mode.
Input signals must be connected to the two channels
you intend to deÞne as measurement and reference
channels.
2. Use the cursor keys to select the desired function,
then press ENTER.
3. Press EXIT to return to normal display.
3-13
Operation
Step 5: Display delta readings
Once the reference channel, measurement channel, and
delta function have been deÞned, press SCAN to halt
triggers. Then press SCAN to start delta measurements. The instrument will automatically display delta
readings computed from signals applied to the reference and measurement channels. If you have selected a
trigger mode that requires a separate trigger for each
reading, you will, of course, have to trigger the instrument to obtain each delta reading (refer to the Model
2001 OperatorÕs Manual for details on triggering).
Canceling the delta mode
Press SCAN to temporarily halt delta readings. To disable scanning, press EXIT.
IEEE-488 bus delta operation
Step 1: Connect inputs
Input signals must be connected to the two channels
you intend to deÞne as measurement and reference
channels.
Step 5: Enable delta mode
Send :ROUT:SCAN:LSEL DELT to enable the delta
mode:
OUTPUT 716; Ò:rout:scan:lsel deltÓ
Step 6: Request delta readings
Once the reference channel, measurement channel, and
delta function have been deÞned, use the DATA? query
to request readings. The following code fragment demonstrates the process:
100OUTPUT 716; Ò:data?Ó
110ENTER 716; A$
120PRINT A$
Canceling the delta mode
To cancel the delta mode, send the :ROUT:SCAN:LSEL
NONE command as follows:
OUTPUT 716; Ò:rout:scan:lsel noneÓ
Step 2: Define measurement channel
Use the :ROUT:SCAN:DELT:MCH command to deÞne
the measurement channel. For example, assume you
wish to deÞne channel 10 as the measurement channel.
The following command would be used:
OUTPUT 716; Ò:rout:scan:delt:mch (@10)Ó
Step 3: Define reference channel
Use :ROUT:SCAN:DELT:RCH to deÞne the reference
channel. The following command would be used to deÞne channel 5 as the reference channel:
OUTPUT 716; Ò:rout:scan:delt:rch (@5)Ó
Step 4: Select measurement function
Send the :ROUT:SCAN:DELT:FUNC command to
select the delta measurement function. For example, to
select DCV, send the following:
3.9RTD temperature measurements
The following paragraphs outline the procedures for
making temperature measurements from the front
panel using the scanner. For more detailed information
on temperature measurements in general, refer to the
Model 2001 OperatorÕs Manual.
Step 1: Connect RTD probes
Connect RTD probes to the scanner using the basic
resistance connections outlined in Section 2. For 4-wire
probes, pair the connections as follows:
¥Channels 1 and 6: probe #1
¥Channels 2 and 7: probe #2
¥Channels 3 and 8: probe #3
¥Channels 4 and 9: probe #4
OUTPUT 716; Ò:rout:scan:delt:func Ôvolt:dcÕÓ
3-14
¥Channels 5 and 10: probe #5
Operation
Step 2: Select sensor type and units
1. From normal display, press CONFIG-TEMP. The
instrument will display the following:
CONFIG TEMPERATURE
SENSORUNITSSPEEDFILTERRESLN
2. Select SENSOR, then press ENTER. The following
will be displayed:
TEMP SENSOR TYPE
RTD4-WIRE-RTDTHERMOCOUPLE
3. Select RTD or 4-WIRE-RTD as appropriate for the
sensor type you are using, then press ENTER. The
instrument will display the following:
SET RTD TYPE
PT385PT3916USER-RTD
4. Select the RTD type from among the displayed
types, then press ENTER.
5. Press EXIT to return to the CONFIG TEMPERATURE menu.
6. Select UNITS, then press ENTER. The unit will display the following selections:
SET TEMP UNITS
DEG-CDEG-FK
3. Use the cursor and range keys to select channels
and functions. Set the function type to TMP for all
channels connected to RTD probes. Select --- (none)
for channels without probes connected.
4. Press ENTER to return to normal display.
Step 4: Configure scan and scan channels
1. From normal display, press CONFIG-SCAN. The
instrument will display the following:
SCAN OPERATION
INTERNALEXTERNALRATIODELTA
2. Select INTERNAL, then press ENTER.
3. Press SCAN, then follow the prompts. See paragraph 3.4.4.
3.10 Using the scanner with the buffer
The Model 2001 internal buffer can be used to store
readings taken while using the scanner. The following
paragraphs outline the steps necessary for fundamental data storage of scanner readings.
7. Choose the type of temperature units you desire to
use: ¡F, ¡C, or K, then press ENTER.
8. Before exiting the temperature conÞguration
menu, select speed, Þlter, and resolution operating
modes, if desired.
9. Press EXIT to return to normal display.
Step 3: Configure channels
1. Press CONFIG-CHAN. The instrument will display the following:
CONFIGURE CHANNELS
INTERNAL-CHANSEXTERNAL-INPUTS
2. Select INTERNAL-CHANS. The Model 2001 will
display the following:
SET INTERNAL CHANNELS
1=DCV2=DCV3=DCV4=DCV5=DCV
Step 1: Configure channels
1. Press CONFIG-CHAN. The instrument will display the following:
CONFIGURE CHANNELS
INTERNAL-CHANSEXTERNAL-INPUTS
2. Select INTERNAL-CHANS. The Model 2001 will
display the following:
SET INTERNAL CHANNELS
1=DCV2=DCV3=DCV4=DCV5=DCV
3. Use the cursor and range keys to select channels
and functions, then press ENTER when you have
set all functions.
4. Press EXIT to return to normal display.
3-15
Operation
Step 2: Configure buffer
1. Press CONFIG-STORE. The unit will display the
following:
CONFIG DATA STORE
BURST-MODEDATA GROUPCONTROL
CLEAR-ALLCOUNTFEED
2. Select COUNT, then press ENTER. The instrument
will display the following:
SET BUFFER SIZE
ENTER-COUNTUSE-TRIGGER-MODEL
3. Select ENTER-COUNT and press ENTER to view
the following:
BUFFER SIZE = 00010
4. Using the cursor and range keys, select the number
of readings to store. Usually, this number will be
the same as the number of channels you are scanning. For example, if you are using all 10 scanner
channels, select 10 readings.
5. Press ENTER to complete programming data storage; then EXIT to return to normal display.
Step 3: Configure scan, perform scan, and recall
readings
1. From normal display, press CONFIG-SCAN. The
instrument will display the following:
using 4-wire measurements. Such tests use the Model
2001 Ω2 and Ω4 resistance functions.
2-wire resistance tests
Figure 3-2 shows a typical test setup for making 2-wire
resistance measurements. The Model 2001-SCAN card
provides the switching function, while the resistance
measurements are made by a Model 2001 Multimeter.
Since only 2-pole switching is required for this
application, one Model 2001-SCAN card can be used to
switch up to 8 resistors. Note, however, that the 275Ω
on resistance of channels 5 and 10 may affect the
measurement accuracy of 2-wire resistance
measurements made using these channels. Generally,
channels 5 and 10 should not be used for 2-wire
resistance measurements.
Measurement accuracy can be optimized by minimizing residual resistance: make connecting wires as short
as possible and limit the number of connectors to minimize path resistance. Another technique is to short one
of the scanner channel inputs, close the shorted channel, and then enable the multimeter REL feature to null
out path resistance. Leave REL enabled for the entire
test.
SCAN OPERATION
INTERNALEXTERNALRATIODELTA
2. Select INTERNAL, then press ENTER.
3. Press SCAN, then follow the prompts. See paragraph 3.4.4.
3.11 Typical applications
3.11.1 Resistor testing
The Model 2001-SCAN can be used to test up to 8 resistors using 2-wire measurements, or up to Þve resistors
3-16
4-wire resistance tests
More precise measurements over a wider range of
system and DUT conditions can be obtained by using
the 4-wire measurement scheme shown in Figure 3-3.
Here, separate sense leads from the Model 2001
Multimeter are routed through the scanner to the
resistor under test. The extra set of sense leads
minimizes the effects of voltage drops across the test
leads, greatly reducing measurement errors with lower
DUT resistances. Note, however, that an extra two
poles of switching are required for each resistor tested.
For this reason, only Þve resistors can be tested using
this conÞguration.
Operation
HI LO
Model 2001
Rear Panel
2001-SCAN
Out A
A. Test Configuration
Ω
2001
Multimeter
2001-SCANDUT
B. Simplified Equivalent Circuit
2001-SCAN
1
1
8
8
DUTs
(10)
Model 2001
Rear Panel
Out A
HI
Sense
HI
LO
Sense
LO
Out B
A. Test Configuration
1
5
6
10
DUTs
(5)
1
5
R
HI
Sense HI
Ω
Sense LO
LO
R
Figure 3-2
2-wire resistance test connections
2001
B. Simplified Equivalent Circuit
2001-SCAN
Figure 3-3
4-wire resistance test connections
DUT
3-17
Operation
Combining 2-pole and 4-pole switching
The Model 2001-SCAN can combine 2- and 4-pole
switching in various combinations. For example, you
might require 4-pole switching for only two resistors,
while the remaining resistors could be tested using
conventional 2-pole switching.
2001-SCAN
Out A
HI
LO
InputHIInput
LO
Figure 3-4 shows a test conÞguration using mixed 2pole and 4-pole switching. Four-pole switching is used
only for device 1 (connected to channels 1 and 6) and
device 2 (connected to channels 2 and 7). Four more
resistors are tested using 2-pole switching.
CH 1
4-Pole
Connections
CH 2
CH 3
Sense
HI
Sense
LO
Model 2001
Rear Panel
Out B
HI
LO
CH 4
CH 5
CH 6
CH 7
CH 8
CH 9
CH 10
2-Pole
Connections
Figure 3-4
Combining 2-pole and 4-pole switching
3-18
DUT's (8)
Operation
Measurement functions for each scanner channel are
deÞned using the INTERNAL-CHANS menu available
by pressing CONFIG-CHAN (see paragraph 3.4).
Measurement functions for this test would be set up as
follows:
Channels 1 and 2: Ω4W
Channels 3, 4 and 8, 9: Ω2W
Note that functions cannot be deÞned for channels 6
and 7 with this application because these channels are
paired with channels 1 and 2 for 4-pole switching.
3.11.2 High-speed multiplexing
Channels 5 and 10 use solid-state switching and can be
used for high-speed multiplexing, as shown in Figure
3-5. In order to use high-speed multiplexing, the scanner card must be operated as follows:
¥The two inputs must be connected to channels 5
and 10.
HI LO
Model 2001
Rear Panel
2001-SCAN
Out A
A. Test Configuration
V
2001
2001-SCANDUT
B. Simplified Equivalent Circuit
V
CH 5
V
CH 10
DUTs
V
¥The Model 2001 must be set to use the internal scan
list.
¥Both channels 5 and 10 must be set for the same
function.
Some typical uses for high-speed multiplexing include:
¥Rapidly switching between two similar signals for
comparison.
¥Automatic ratio and delta computations using the
built-in ratio or delta modes.
Figure 3-5
Connections for high-speed multiplexing
3.11.3 Current measurements
Although the Model 2001-SCAN is not intended for
direct current measurements, on-card shunt resistors
can be installed for channels 1 and 6 to allow for indirect current measurements. Figure 3-6 shows the typical conÞguration for current measurements. Refer to
Section 2 for speciÞc information on recommended
shunt resistors and their installation.
3-19
Operation
The current through each shunt resistor can be calculated as follows:
V
I
--- -=
R
Where:I = current being determined
V = voltage measured by Model 2001
R = shunt resistance value
Instead of manually calculating current, set up a Model
2001 mx + b math calculation function. (Here, m = 1/R
and b = 0.). The Model 2001 will then display the actual
current value. Refer to the Model 2001 OperatorÕs
Manual for details on using math functions.
User-installed
Shunts
A
A
DUTs
(2)
Model 2001
Rear Panel
2001-SCAN
CH 1
Out A
HI
LO
CH 6
A. Test Configuration
3.12 Measurement considerations
Many measurements made with the Model 2001SCAN are subject to various effects that can seriously
affect low-level measurement accuracy. The following
paragraphs discuss these effects and ways to minimize
them.
3.12.1 Path isolation
The path isolation is simply the equivalent impedance
between any two test paths in a measurement system.
Ideally, the path isolation should be inÞnite, but the
actual resistance and distributed capacitance of cables
and connectors results in less than inÞnite path isolation values for these devices.
Path isolation resistance forms a signal path that is in
parallel with the equivalent resistance of the DUT, as
shown in Figure 3-7. For low-to-medium device resistance values, path isolation resistance is seldom a consideration; however, it can seriously degrade
measurement accuracy when testing high-impedance
devices. The voltage measured across such a device, for
example, can be substantially attenuated by the voltage divider action of the device source resistance and
path isolation resistance, as shown in Figure 3-8. Also,
leakage currents can be generated through these resistances by voltage sources in the system.
User-installed
V
2001
B. Simplified Equivalent Circuit
2001-SCANDUT
Figure 3-6
Connections for current measurements
3-20
Shunt
R
A
R
DUT
R
PATH
E
DUT
DUT
= Source Resistance of DUT
R
DUT
E
= Source EMF of DUT
DUT
= Path Isolation Resistance
PATH
R
= Input Resistance of Model 2001
IN
Scanner
Card
R
IN
Model 2001
V
Figure 3-7
Path isolation resistance
Operation
R
DUT
E
OUT
E
DUT
DUT
R
R
PATH
R
PATH
PATH
E
DUT
E
OUT
R
Figure 3-8
Voltage attenuation by path isolation resistance
3.12.2 Channel resistance
The on resistance of channels 5 and 10 (the solid-state
channels) is speciÞed as <275Ω. For this reason, you
should not use channels 5 and 10 for low-to-medium
resistance measurements (<100kΩ). For example, measuring a 1kΩ resistor using channel 5 or channel 10 will
result in an error of more than 25%.
produced by various signals such as the AC power line
voltage. Large inductors such as power transformers
can generate substantial magnetic Þelds, so care must
be taken to keep the switching and measuring circuits
a good distance away from these potential noise sources. At high current levels, even a single conductor can
generate signiÞcant Þelds. These effects can be minimized by using twisted pairs, which will cancel out
most of the resulting Þelds.
3.12.4 Electromagnetic interference (EMI)
The electromagnetic interference characteristics of the
Models 2001/2002 Multimeters comply with the electromagnetic compatibility (EMC) requirements of the
European Union (EU) directives as denoted by the CE
mark. However, it is still possible for sensitive measurements to be affected by external sources. In these
instances, special precautions may be required in the
test setup.
Sources of the EMI include:
¥Radio and TV broadcast transmitters.
¥Communications transmitters, including cellular
phones and handheld radios.
3.12.3 Magnetic fields
When a conductor cuts through magnetic lines of force,
a very small current is generated. This phenomenon
will frequently cause unwanted signals to occur in the
test leads of a scanning system. If the conductor has
sufÞcient length, even weak magnetic Þelds like those
of the earth can create sufÞcient signals to affect lowlevel measurements. Two ways to reduce these effects
are: (1) reduce the lengths of the test leads, and (2) minimize the exposed circuit area. In extreme cases, magnetic shielding may be required. Special metal with
high permeability at low ßux densities (such as mu
metal) is effective at reducing these effects.
Even when the conductor is stationary, magneticallyinduced signals may still be a problem. Fields can be
¥Devices incorporating microprocessors and high-
speed digital circuits.
¥Impulse sources as in the case of arcing in high-
voltage environments.
The instrument, measurement leads, and other cables
should be kept as far away as possible from any EMI
sources. Shielding measurement leads and the
multimeter may reduce EMI to acceptable levels. In
extreme cases, a specially constructed screen room may
be required to sufÞciently attenuate troublesome
signals.
Many instruments incorporate internal Þltering that
may help reduce EMI effects. In some cases, additional
external Þltering may be required. Keep in mind, however, that Þltering may have detrimental effects on the
measurement.
3-21
Operation
3.12.5 Ground loops
When two or more instruments are connected together,
care must be taken to avoid unwanted signals caused
by ground loops. Ground loops usually occur when
sensitive instrumentation is connected to other
instrumentation with more than one signal return path
such as power line ground. As shown in Figure 3-9, the
resulting ground loop causes current to ßow through
the instrument LO signal leads and then back through
power line ground. This circulating current develops a
small but undesirable voltage between the LO
terminals of the two instruments. This voltage will be
added to the source voltage, affecting the accuracy of
the measurement.
Signal Leads
Instrument 1Instrument 2Instrument 3
Ground Loop
Current
Power Line Ground
Figure 3-9
Power line ground loops
Instrument 1Instrument 2Instrument 3
Power Line Ground
Figure 3-10
Eliminating ground loops
3.12.6 Keeping connectors clean
As is the case with any high-resistance device, the
integrity of connectors can be compromised if they are
not handled properly. If connector insulation becomes
contaminated, the insulation resistance will be substantially reduced, affecting high-impedance measurement paths. Oils and salts from the skin can
contaminate connector insulators, reducing their resistance. Also, contaminants present in the air can be
deposited on the insulator surface. To avoid these
problems, never touch the connector insulating material. In addition, the scanner card should be used only
in clean, dry environments to avoid contamination.
Figure 3-10 shows how to connect several instruments
together to eliminate this type of ground loop problem.
Here, only one instrument is connected to power line
ground. Ground loops are not normally a problem
with instruments having isolated LO terminals. However, all instruments in the test setup may not be
designed in this manner. When in doubt, consult the
manual for all instrumentation in the test setup.
3-22
If the connector insulators should become contaminated, either by inadvertent touching, or from airborne deposits, they can be cleaned with a cotton swab
dipped in clean methanol. After thoroughly cleaning,
they should be allowed to dry for several hours in a
low-humidity environment before use, or they can be
dried more quickly using dry nitrogen.
4
Service Information
WARNING
The information in this section is
intended only for qualiÞed service
personnel. Some of the procedures
may expose you to hazardous voltages that could result in personal
injury or death. Do not attempt to
perform these procedures unless you
are qualiÞed to do so.
4.1Introduction
This section contains information necessary to service
the Model 2001-SCAN scanner card and is arranged as
follows:
4.2 Handling and cleaning precautions: Discusses
handling precautions and methods to clean the
card should it become contaminated.
4.3 Performance veriÞcation: Covers the procedures
necessary to determine if the scanner card meets
stated speciÞcations.
4.4 Special handling of static-sensitive devices: Re-
views precautions necessary when handling static-sensitive devices.
4.5 Principles of operation: Brießy discusses circuit
operation.
4.6 Troubleshooting: Presents some troubleshooting
tips for the Model 2001-SCAN including relay
replacement precautions.
4.2Handling and cleaning precautions
Because of the high-impedance areas on the Model
2001-SCAN, care should be taken when handling or
servicing the card to prevent possible contamination.
The following precautions should be observed when
servicing the card.
4.2.1Handling precautions
¥Handle the card only by the edges and shields.
¥Do not touch any board surfaces or components
not associated with the repair.
¥Do not touch areas adjacent to electrical contacts.
¥When servicing the card, wear clean cotton gloves.
¥Do not store or operate the card in an environment
where dust could settle on the circuit board.
¥Use dry nitrogen gas to clean dust off the board if
necessary.
4-1
Service Information
4.2.2Soldering precautions
Should it become necessary to use solder on the circuit
board, observe the following precautions:
¥Use an OA-based (organic activated) ßux, and take
care not to spread the ßux to other areas of the circuit board.
¥Remove the ßux from the work areas when the
repair has been completed. Use pure water along
with clean cotton swabs or a clean, soft brush to
remove the ßux.
¥Once the ßux has been removed, swab only the
repaired area with methanol, then blow dry the
board with dry nitrogen gas.
¥After cleaning, the card should be allowed to dry
in a 50¡C low-humidity environment for several
hours before use.
4.3Performance verification
The following paragraphs discuss performance veriÞcation procedures for the Model 2001-SCAN, including
path resistance, contact potential, and isolation.
touch connector insulators, board
surfaces, or components.
NOTE
Failure of any performance veriÞcation test may indicate that the scanner
card is contaminated. See paragraph
4.2 for information on cleaning the
card.
4.3.1Environmental conditions
All veriÞcation measurements should be made at an
ambient temperature between 18¡ and 28¡C, and at a
relative humidity of less than 70%.
4.3.2Recommended equipment
Table 4-1 summarizes the equipment necessary for performance veriÞcation, along with an application for
each item.
CAUTION
Contamination will degrade the performance of the card. To avoid contamination, always grasp the card by
the side edges and covers. Do not
Table 4-1
Recommended verification equipment
DescriptionModel/partSpeciÞcationsApplication
Multimeter Keithley Model 2001 20
Electrometer with voltage
source
Sensitive Digital VoltmeterKeithley Model 1823mV; 60ppmContact potential
Triax cable (unterminated)Keithley Model 7025--Path isolation
Low-thermal cableKeithley Model 1484--Contact potential
#22AWG solid copper wire---- Path resistance
#22AWG Teßon-insulated
stranded wire
Keithley Model 61710pA, 100pA; 1.6%.
----Path isolation
4.3.3Scanner card connections
Jumper wires or connecting cables can simply be hardwired directly to the screw terminals of the Model
2001-SCAN. Detailed connection information is provided in Section 2.
Ω
; 72ppm Control card, measure path
resistance
Path isolation
100V source; 0.2%
4-2
.
Service Information
4.3.4Path resistance tests
Perform the following steps to verify that the path
resistance of each channel is with speciÞed values.
1. Connect the HI and LO terminals of all 10 channel
inputs together to make one common terminal
using #22AWG solid copper jumper wires (see Figure 4-1).
NOTE
Make sure that all jumper wires are
clean and free of oxides.
2. Connect the output cables to OUT A HI and LO, as
shown in Figure 4-1.
3. With the power off, install the scanner card in the
Model 2001 Multimeter.
4. Turn on the Model 2001, and allow it to warm up
for one hour before proceeding.
5. Select the
Model 2001.
6. Temporarily connect a second set of output leads,
identical in length and type to the leads connected
to the scanner card output, to the Model 2001 rear
panel HI and LO INPUT jacks. Be sure to select the
rear panel terminals with the front panel INPUT
switch.
7. Short the free ends of the temporary leads together,
and allow the reading to settle. Enable the Model
2001 REL mode after settling, and leave REL
enabled for the remainder of the path resistance
tests.
8. Disconnect the temporary leads from the multimeter, and connect the output leads from the scanner
card to the rear panel HI and LO INPUT jacks (see
Figure 4-1).
Ω
2W function and the 20
Ω
range on the
9. Close channel 1 as follows;
A. From normal display, press CHAN. The instru-
ment will display the following:
CHANNEL SELECTION
CLOSE-CHANNELOPEN-ALL-CHANNELS
B. Select CLOSE-CHANNEL, then press ENTER.
The Model 2001 will display the following:
ENTER CHAN#01 (1-10)
C. Using the range and cursor keys, select channel
01, then press ENTER.
D. Press EXIT to return to normal display.
10. Note the resistance reading on the Model 2001.
Verify that the reading is <2
11. Repeat steps 9 and 10 for channels 2-9. Verify that
the path resistance for each channel is as follows:
¥Channels 1-4, 6-9: <2
¥Channels 5 and 10: <550
NOTE
Change to the 2k
when measuring channels 5 and 10.
Always use the lowest possible range
for best accuracy.
12. After completing the tests, turn off the Model 2001
power, remove the scanner card, and remove all
jumper wires (leave HI and LO shorted for each
channel if you intend to perform contact potential
tests).
Ω
.
Ω
.
Ω
Ω
resistance range
4-3
Service Information
Jumper HI and LO
of all 10 Channels
Channel 1
Channel 2-4
Channel 5
HI
LO
HI
LO
4-Pole
2-Pole
HI
LO
HI
LO
OUT A
OUT B
InputHIInput
LO
Model 2001
Rear Panel
Channel 6
Channel 7-9
Channel 10
HI
LO
HI
LO
Model 2001-SCAN
Figure 4-1
Connections for path resistance checks
4.3.5Contact potential tests
These tests check the EMF (contact potential) generated by each relay contact pair (HI and LO) for each
channel. The tests use a sensitive digital voltmeter
(Model 182) to measure the contact potential.
3. With the power off, install the scanner card in the
Model 2001 Multimeter.
4. Turn on the Model 2001 and the Model 182 Sensitive Digital Voltmeter. Allow the Model 182 to
warm up for two hours before measurement.
5. Select the 3mV range on the Model 182.
Perform the following procedure to check contact potential of each channel.
1. Connect 1Ó #22AWG copper jumper wires
between the HI and LO terminals of each channel
input (see Figure 4-2).
2. Connect the Model 182 to OUT A HI and LO using
the low-thermal cable (see Figure 4-2).
4-4
6. Select the DCV function on the Model 2001.
7. Using the CHAN key, close channel 1 (see paragraph 4.3.4 for procedure).
8. Verify that the Model 182 reading is <1µV.
9. Repeat steps 7 and 8 for all 10 channels.
10. After completing all measurements, turn off the
Model 2001 power, remove the scanner card, and
disconnect all jumpers and test leads.
Service Information
Model 1484
Low Thermal Cable
(Unterminated)
KEITHLEY
182 SENSITIVE DIGITAL VOLTMETER
TRG
SRQ
REM
TALK
LSTN
Connect bare copper jumpers between
HI and LO of each channel
HI
Channel 1
LO
Channel 2-4
HI
Channel 5
LO
4-Pole
Channel 6
HI
LO
Channel 7-9
Channel 10
HI
LO
2-Pole
Model 182
HI
OUT A
LO
HI
OUT B
LO
Model 2001-SCAN
Figure 4-2
Connections for contact potential tests
4-5
Service Information
4.3.6Isolation tests
These tests check the leakage resistance (isolation)
between all HI and LO terminals and from HI and LO
terminals to chassis ground. In general, the test is performed by applying a voltage (100V) across the terminals and then measuring the leakage current. The
isolation resistance is then calculated as R = V/I. In the
following procedure, the Model 617 functions as a voltage source and as an ammeter. In the V/I function, the
Model 617 internally calculates the resistance from the
known voltage and current levels, and displays the
resistance value.
Perform the following steps to check isolation:
1. Connect a 4Ó length of Teßon-insulated #22AWG
stranded wire to every HI and LO terminal on the
scanner card (both inputs and outputs). Mark the
free end of each wire so you can identify wires
when the scanner card is installed.
2. With the power off, install the scanner card in the
multimeter.
3. Turn on the Model 2001 power.
4. Turn on the Model 617, and allow the unit to warm
up for two hours for rated accuracy.
5. Select the Model 617 2pA range, and enable zero
check and zero correct in that order. Leave zero
correct enabled for the entire procedure.
WARNING
The following steps use high voltage
(100V). Be sure to remove power
from the circuit before making connection changes.
6. Set the Model 617 voltage source for +100V, and
select the 200nA current range. Make sure the voltage source is still in standby.
7. Place the Model 617 in the V/I measurement function by pressing SHIFT OHMS.
8. With the Model 617 in standby, connect the electrometer to OUT A HI and LO terminals of the
scanner card, as shown in Figure 4-3.
9. Close channel 1 using the CHAN key (see paragraph 4.3.4 for details).
10. On the Model 617, disable zero check, and press
OPERATE to source 100V.
11. After allowing the reading on the Model 617 to settle, verify that the reading is >1G
Ω
(10
9
Ω
). This
measurement represents the isolation resistance
between the HI and LO terminals of channel 1.
12. Place the Model 617 in standby, and enable zero
check.
13. Repeat steps 9 through 12 for channels 2 through
10. Be sure that the channel under test is closed.
14. With the Model 617 voltage source in standby, connect the electrometer to the HI terminals of scanner
card channels 1 and 2, as shown in Figure 4-4.
15. Close channel 1 using the CHAN key.
16. On the Model 617, disable zero check, and press
OPERATE to source 100V.
17. After allowing the reading on the Model 617 to settle, verify that the reading is >1G
Ω
(10
9
Ω
). This
measurement represents the isolation resistance
between the HI terminals of channels 1 and 2.
18. Place the Model 617 in standby, and enable zero
check.
19. Repeat steps 14 through 18 to measure isolation
resistance between the channel 1 HI terminal and
channels 3 through 10 HI terminals. Be sure that
the electrometer is connected to the HI terminals of
the two channels being tested, and that channel 1 is
closed.
20. Repeat steps 14 through 19 for the LO terminals of
channels 1 through 10. Be sure the electrometer is
connected to the LO terminals of the two channels
being tested, and that channel 1 is closed.
21. With the electrometer voltage source in standby,
connect the electrometer to channel 1 HI and chassis ground, as shown in Figure 4-5.
22. Program the Model 2001 to close channel 1.
23. On the Model 617, disable zero check, and press
OPERATE to source +100V.
24. After allowing the reading on the Model 617 to settle, verify that it is >1G
Ω
(10
9
Ω
).
25. Put the electrometer in standby, and enable zero
check.
26. Repeat steps 21 through 25 for channels 2 through
10. One electrometer lead should be connected to
the HI terminal of the channel being testing, and
the other lead should be connected to chassis
ground.
27. Repeat steps 21 through 26 for channels 1 through
10 LO terminals. One electrometer lead should be
connected to the LO terminal of the channel being
tested, and the other lead should be connected to
chassis ground. In addition, channel 1 should be
closed.
4-6
V-Source LO
V-Source HI
Source V and
Measure V/I
Banana to Banana Cable
Ground Link
Removed
INPUT
Com
Model 617
Unterminated to
Banana Cable
Model 7025
Unterminated
Triax Cable
HI
(Red)
Channel 1
Channel 2-4
Channel 5
HI
LO
HI
LO
4-Pole
Service Information
HI
OUT A
LO
HI
OUT B
LO
2-Pole
Figure 4-3
Connections for same-channel isolation tests
Channel 6
Channel 7-9
Channel 10
HI
LO
HI
LO
Model 2001-SCAN
4-7
Service Information
Banana to Banana Cable
Ground Link
Removed
V-Source LO
V-Source HI
Source V and
Measure V/I
INPUT
Model 617
Com
Unterminated to
Banana Cable
Model 7025
Unterminated
Triax Cable
HI
(Red)
Channel 1
Channel 2-4
Channel 5
HI
LO
2-Pole
HI
LO
HI
LO
OUT A
OUT B
HI
LO
4-Pole
Figure 4-4
Connections for channel-to-channel isolation tests
Channel 6
Channel 7-9
Channel 10
HI
LO
HI
LO
Model 2001-SCAN
4-8
V-Source LO
V-Source HI
Source V and
Measure V/I
Banana to Banana Cable
Ground Link
Removed
INPUT
Com
Model 617
Unterminated to
Banana Cable
Model 2001
Chassis Ground
Model 7025
Unterminated
Triax Cable
HI
(Red)
Channel 1
Channel 2-4
Channel 5
HI
LO
HI
LO
4-Pole
Service Information
HI
OUT A
LO
HI
OUT B
LO
2-Pole
Channel 6
Channel 7-9
Channel 10
Figure 4-5
Connections for HI and LO terminal to chassis ground isolation tests
4.4Special handling of static-sensitive
devices
CMOS and other high-impedance devices are subject
to possible static discharge damage because of the
high-impedance levels involved. When handling such
devices, use the precautions listed below.
dissipate static build-up. Typically, these devices
will be received in anti-static containers made of
plastic or foam. Keep these parts in their original
containers until ready for installation or use.
2. Remove the devices from their protective containers only at a properly grounded workstation. Also,
ground yourself with an appropriate wrist strap
while working with these devices.
HI
LO
HI
LO
Model 2001-SCAN
NOTE
In order to prevent damage, assume
that all parts are static-sensitive.
1. Such devices should be transported and handled
only in containers specially designed to prevent or
3. Handle the devices only by the body; do not touch
the pins or terminals.
4. Any printed circuit board into which the device is
to be inserted must Þrst be grounded to the bench
or table.
5. Use only anti-static type de-soldering tools and
grounded-tip soldering irons.
4-9
Service Information
4.5Principles of operation
The following paragraphs discuss the basic operating
principles for the Model 2001-SCAN, and can be used
as an aid in troubleshooting the card. The schematic
drawing of the card is shown on drawing number
2001-176, located at the end of Section 5.
4.5.1Block diagram
Figure 4-6 shows a simpliÞed block diagram of the
Model 2001-SCAN. Key elements include the relay
drivers and relays, as well as the solid-state switches,
and the power-up reset circuit. These various elements
are discussed in the following paragraphs.
To 2001
Multimeter
Clock
Data
Strobe
+5V
Relay
Drivers
U101-U103
Power-on
Reset
U104
Enable
Relays,
Solid-state
Switches
K101-K111
U105, U106
User Connections
4.5.3Switching circuits
Relays K101 through K106 and K108 to K111 perform
input switching, while K107 conÞgures the card for 2pole or 4-pole operation. U105 and U106 are the solidstate switching elements used for channels 5 and 10.
Note that relay switching is also incorporated into
channels 5 and 10 along with the solid-state switches.
K110 switches channel 5, and K111 switches channel
10. Solid-state switching is only used when the internal
scan listed is selected, when only channels 5 and 10 are
in the internal scan list, and if the same function is used
for both channels 5 and 10. Otherwise, the latching relays K110 and K111 are used to switch channels 5 and
10.
4.5.4Power-on safeguard
A power-on safeguard circuit, made up of U104 and
associated components, ensures that relays do not
change state on power-up and power-down. This circuit disables all relay actuation during power-up and
power-down periods by holding the OE (output enable
lines) high during these periods.
Figure 4-6
Block diagram
4.5.2Relay control
Card relays are controlled by serial data transmitted
via the relay DATA line. A total of three bytes are shifted in serial fashion into latches located in the card relay
driver ICs. The serial data is clocked in by the CLOCK
line. As data overßows one register, it is fed out the QÕS
line of the register down the chain.
Once all three bytes have shifted into the card, the
STROBE line is set high to latch the relay information
into the Q outputs of the relay drivers, and the appropriate relays are energized (assuming the driver outputs are enabled, as discussed below). Note that a relay
driver output goes low to energize the corresponding
relay.
4.6Troubleshooting
4.6.1Troubleshooting equipment
Table 4-2 summarizes recommended equipment for
troubleshooting the Model 2001-SCAN.
Table 4-2
Recommended troubleshooting equipment
Manufacturer
Description
MultimeterKeithley 2001DCV checks
OscilloscopeTEK 2243View logic wave-
and modelApplication
forms
4-10
Service Information
4.6.2Troubleshooting access
In order to gain access to the scanner card circuit board
to measure voltages under actual operating conditions,
perform the following steps:
1. Turn off the Model 2001 power, and disconnect the
line cord and all other equipment.
2. If wires are connected to the scanner card, remove
the scanner card from the multimeter.
3. Remove the Model 2001 cover as follows:
A. Remove the handle by rotating it to align the
arrows on the handle mounting ears. Pull out
and remove the handle.
B. Remove the screws that secure the handle
mounting ears, then remove the ears.
C. Remove the screws that attach the rear bezel to
the case, then remove the bezel.
D. Remove the bottom screw that grounds the
case to the chassis.
WARNING
Be sure to install and tighten the
grounding screw after replacing the
cover.
E. Remove the cover by pulling it off towards the
rear.
4. Disconnect any wires connected to the scanner
card terminal blocks.
5. Install the scanner card in the multimeter.
6. Connect the line cord, and turn on the power to
measure voltages (see following paragraph).
4.6.3Troubleshooting procedure
Table 4-3 summarizes scanner card troubleshooting
steps. Refer to the schematic diagram and component
layout drawings at the end of Section 5 for component
locations.
WARNING
Lethal voltages are present within
the Model 2001. Some of the procedures may expose you to hazardous
voltages. Observe standard safety
precautions for dealing with live circuits. Failure to do so could result in
personal injury or death.
CAUTION
Observe the following precautions
when troubleshooting or repairing
the switch card:
To avoid contamination, which could
degrade card performance, always
handle the card only by the side edges and covers. Do not touch edge connectors, board surfaces, or
components on the card. Also, do not
touch areas adjacent to electrical contacts on connectors.
Use care when removing relays from
the PC board to avoid pulling traces
away from the circuit board. Before
attempting to remove a relay, use an
appropriate de-soldering tool, such
as a solder sucker, to clear each
mounting hole completely free of
solder. Each relay pin must be free to
move in its mounting hole before removal. Also, make certain that no
burrs are present on the ends of the
relay pins.
4-11
Service Information
Table 4-3
Troubleshooting procedure
StepItem/componentRequired conditionComments
1Digital ground P1034, pin 1,
3, 5
All voltages referenced to
digital ground.
2P1034, pin 9 +5VDCCard power supply volt-
age.
3U101, pin 2 CLOCK pulsesSerial clock pulses.
4U101, pin 3 DATA pulsesSerial data pulses.
5U101, pin 7 STOBE pulseEnd of relay update
sequence.
6U101-U103, pins 10-18 Low when relay state is changed.
Relay driver outputs.
High when relay is not changing
state.
4-12
5
Replaceable Parts
5.1Introduction
This section contains replacement parts information,
schematic diagram, and component layout drawing
for the Model 2001-SCAN.
5.2Parts list
A parts list for the scanner card is included in a table
integrated with schematic diagram and component
layout drawing for the board. Parts are listed alphabetically in order of circuit designation.
5.3Ordering information
To place an order, or to obtain information concerning
replacement parts, contact your Keithley representative or the factory (see inside front cover for addresses).
When ordering parts, be sure to include the following
information:
¥Card model number (2001-SCAN)
¥Card serial number
¥Part description
5.4Factory service
If the card is to be returned to Keithley Instruments for
repair, perform the following:
¥Call the Instruments Division Repair Department
at 1-800-552-1115 for a Return Material Authorization (RMA) number.
¥Complete the service form at the back of this man-
ual and include it with the card.
¥Carefully pack the card in the original packing
carton.
¥Write ATTENTION REPAIR DEPT and the RMA
number on the shipping label.
NOTE: It is not necessary to return the Model 2001
Multimeter with the card.
5.5Component layout and schematic
diagrams
A component layout drawing and schematic diagram
are included on the following pages integrated with
the parts list for the Model 2001-SCAN.
¥Circuit description, if applicable
¥Keithley part number
5-1
IEEE-488 Reference
Model 2001-SCAN, parts list
Circuit
Desig.Description
CARD EJECTOR
SHIELD, SCANNER BOTTOM
STRAIN RELIEF, BOTTOM
SHIELD, SCANNER TOP
SLEEVED BANANA PLUG TEST LEAD
Open and close channels (CHAN) 3-3
Opening channels 3-9
Operation 3-1
Ordering information 5-1
Output connections 2-4
Output connections to multimeter 2-16
i-1
P
Parts list 5-1
Path isolation 3-20
Path resistance tests 4-3
Performance verification 4-2
Power-on safeguard 4-10
Power-up detection 3-2
Principles of operation 4-10
R
Ratio and delta 3-11
Ratio and delta computation 3-11
Ratio and delta measurement functions
3-11
Ratio and delta triggering 3-11
Ratio operation 3-11
RATIO/DELTA channel selection 3-6
Recommended current shunt values 2-11
Recommended equipment 4-2
Relay control 4-10
Relay input signal limitations 3-2
Repacking for shipment 1-2
Replaceable parts 5-1
Resistance connections 2-8
Resistor testing 3-16
RTD temperature measurements 3-14
S
Safety symbols and terms 1-2
Scan configuration (CONFIG-SCAN) 3-5
Scanner card connections 4-2
Scanner card detection 3-2
Scanner card installation 2-14
Scanner card removal 2-16
Scanner option bus query 3-2
Scanning channels 3-9
Service information 4-1
Shipment contents 1-2
Signal limitations 3-2
Soldering precautions 4-2
Solid-state input signal limitations 3-2
Solid-state switching 3-11
Solid-state switching considerations 3-6
Special handling of static-sensitive devices