Keithley 2281S Series User manual

2281S Precision DC Supply and Battery Simulator
Quick Start Guide

Safety precautions
Observe the following safety precautions beforeusing this productandany associated
instrumentation.Although some instruments and accessories would normally beused with
nonhazardousvoltages, there aresituationswhere hazardous conditions may be present.
This productis intendedfor use by qualified personnel who recognize shock hazards andare
familiar with the safety precautions required toavoid possible injury.Readand follow all
installation, operation, and maintenance information carefullybefore using the product.
Refer to the user documentation for complete product specifications.
If the product is usedin a manner notspecified,theprotection providedby the product
w arrantymay be impaired.
The types of product users are:
Responsible body is the individual orgroupresponsible for useandmaintenance of
equipment,for ensuring that the equipment is operatedwithinits specifications and
operating limits, and for ensuring that operators areadequately trained.
Operators use the product for its intended function.Theymust be trained in electrical
safety proceduresand proper useof the instrument. They must beprotected from electric
shock and contact with hazardous live circuits.
Maintenance personnel perform routine procedures on the producttokeep it operating
properly, for example, setting the line voltage or replacing consumable materials.
Maintenance proceduresare described in the user documentation. The procedures explicitly
state if the operator may perform them. Otherwise,they should be performedonlyby
service personnel.
Service personnel are trained to workon live circuits, performsafe installations,and
repair products. Only properly trainedservice personnel mayperform installation andservice
procedures.
Keithley Instruments products are designedfor use with electrical signals thatare
measurement, control,anddata I/Oconnections, with low transientovervoltagesandmust
not be directly connectedto mains voltageor tovoltagesources withhigh transient
overvoltages. Measurement CategoryII (as referencedin IEC 60664)connections require
protection for high transientovervoltages often associated with local AC mains connections.
Certain Keithley measuring instruments maybe connectedto mains.These instruments will
be marked as categoryII or higher.
Unless explicitly allowed in the specifications, operating manual, and instrumentlabels, do
not connect any instrumentto mains.
Exercise extreme caution whena shockhazard is present.Lethal voltagemay be present on
cable connectorjacks or test fixtures. TheAmerican National Standards Institute (ANSI)
states thata shock hazard exists when voltage levelsgreater than 30 V RMS, 42.4 V peak,or
60 V DC are present.A good safety practice isto expectthat hazardous voltage is present in
any unknown circuitbeforemeasuring.
Operators of this product must be protectedfrom electric shock at all times. Theresponsible
body must ensurethat operators are prevented access and/or insulated from every
connection point. In some cases,connectionsmust be exposedto potential human contact.
Product operators inthesecircumstances must be trained toprotectthemselvesfrom the
risk of electricshock. If the circuit iscapable of operating ator above 1000 V, no conductive
part of the circuit may beexposed.

Do not connectswitching cards directly to unlimitedpower circuits. Theyare intendedto be
used with impedance-limitedsources. NEVER connect switching cardsdirectlyto AC
mains. Whenconnecting sources to switching cards, install protective devices to limitfault
current and voltage to the card.
Before operating aninstrument, ensurethat the line cord is connected toa
properly-grounded power receptacle. Inspect the connecting cables, test leads, and jumpers
for possible wear, cracks, or breaks before each use.
When installing equipment where access to themain power cord is restricted, such as rack
mounting, a separatemain inputpower disconnect device must be provided inclose
proximity totheequipmentandwithineasy reach oftheoperator.
For maximum safety, donottouch the product, test cables,or anyother instruments while
power is applied tothecircuit under test. ALWAYSremovepower from the entiretest
system and discharge any capacitors before:connecting or disconnecting cables or jumpers,
installing or removing switching cards,or making internal changes, suchas installing or
removing jumpers.
Do not touchany objectthat could provide a currentpath to the common sideof the circuit
under test or power line (earth) ground.Always make measurements with dry hands while
standing on a dry, insulated surface capable ofwithstanding thevoltagebeing measured.
For safety, instruments and accessories must beused inaccordance withtheoperating
instructions.Ifthe instruments or accessories areused ina manner not specified in the
operating instructions,the protection providedby the equipment may beimpaired.
Do not exceed the maximum signal levels of the instruments and accessories, as definedin
the specifications and operating information, and as shown on the instrumentor test fixture
panels, or switching card.
When fuses are used in aproduct, replace with the sametype andrating for continued
protection against fire hazard.
Chassis connections must only be used as shield connections for measuring circuits, NOT as
protective earth (safety ground)connections.
If you are using a test fixture,keep the lid closed whilepower isappliedto the device under
test. Safe operationrequiresthe use of a lid interlock.
If a screw is present, connect itto protectiveearth (safety ground) using thewire
recommendedin the user documentation.
This symbol on aninstrument means caution, risk of danger. The user should
refer to the operating instructions locatedin the user documentationin allcases
w here the symbol is markedon the instrument.
This symbol on aninstrument means caution, risk of electricshock. Use
standard safety precautions to avoid personal contactwith these voltages.
This symbol on aninstrument shows thatthesurface may be hot. Avoid
personal contactto preventburns.
This symbol indicates a connection terminal to the equipment frame.
If the mercury symbol is on aproduct, it indicates thatmercury is presentin the
display lamp. Please note thatthelamp must be properly disposed of according
to federal, state, andlocal laws.
WARNING
This heading in the userdocumentation explains dangers that might
result in personal injury or death. Always readtheassociated
information very carefully before performing the indicatedprocedure.
CAUTION
This heading in the userdocumentation explains hazards thatcould
damage the instrument. Such damage may invalidate the warranty.
Instrumentation and accessoriesshall not be connected to humans.
Before performing any maintenance,disconnectthe line cord and all testcables.

To maintain protectionfrom electric shock andfire, replacement components in mains
circuits —including thepower transformer,test leads, and inputjacks —must be purchased
from Keithley Instruments. Standard fuses with applicable national safety approvalsmaybe
used if the rating and type arethesame. Other components that are not safety-related may be
purchased from other suppliers as long asthey areequivalent totheoriginal component
(note that selectedparts should be purchased only through KeithleyInstruments tomaintain
accuracy and functionalityof the product). If youare unsure about the applicability of a
replacement component, call a Keithley Instruments office for information.
To clean an instrument, remove power fromthe instrument. Use a damp cloth or mild,
w ater-based cleaner. Cleantheexterior of the instrumentonly. Donotapply cleaner directly
to the instrument or allow liquids to enter or spill onthe instrument. Products that consist of
a circuit board withno caseor chassis (e.g., adata acquisitionboard for installation into a
computer) shouldnever requirecleaning if handled according toinstructions. If the board
becomes contaminatedandoperation isaffected, the board should be returned to the factory
for proper cleaning and servicing.
Safety precaution revision ofJanuary 2013.
Power and environmental specifications
For indoor use only.
Power supply
100 V AC/120 V AC/220 V AC/240 V AC, 50 Hz or 60
Hz
Operating altitude
Max imum 2000 m (6562 ft) abov e sea level
Operating
temperature
0 °C to 40 °C (32 °F to 104 °F), full accuracy to 80 %
relativ e humidity at up to 35 °C (95 °F), non-
condensing
Storage temperature
-20 °C to 70 °C (-4 °F to 158 °F), 5 % to 95 % relativ e
humidity atup to 40 °C (+104 °F) and 5 % to 60 % RH
abov e 40 °C (+104 °F) up to 70 °C (+158 °F)
Pollution degree
2
Carefully consider and configure the appropriate output-off
state, and source and compliance levels before connecting the
instrument to a device that can deliver energy. Failure to
consider the output-off state and source and limit levels may
result in damage to the instrument or to the device under test.

Introduction
Thank you for choosing a Keithley Instruments product. The
Model 2281S Precision DC Supply and Battery Simulator is a highly
sensitive, accurate, programmable power supply that sources stable
low-noise voltage, and monitors load currents over a wide dynamic
range from amperes to nanoamperes,. It can also test batteries and
generate battery models to simulate batteries.
The high-resolution 4.3 inch color display shows numerous
parameters that describe the state of the instrument to enable you to
get the most information from your measurements.
You can generate and edit battery models on the display. In addition,
the capacity and voltage changes are shown on the display during the
battery simulation.
Model
number
Description
2281S-20-6
Precision DC Supply and Battery Simulator, 20 V, 6 A
CD-ROM contents
The CD-ROM that is included with your instrument contains PDFs
of the Reference Manual, Quick Start Guide, and accessory manuals.
For additional support information, see
http://www.tek.com/keithley.

Unpack and inspect the instrument
1. Inspect the box for damage.
2. Open the top of the box.
3. Remove the bag that contains the documentation, standard
accessories, CD-ROM, and cable housing.
4. Remove the packaging insert.
5. Remove the 2281S from the box.
Do not lift the 2281S from the front bezel. Lifting the instrument
by the front bezel can cause instrument damage.
6. Inspect the instrument for any obvious signs of physical
damage. Report any damage to the shipping agent immediately.

You should have received the 2281S with the following accessories,
shown in the photograph:
1Power line cord
2KickStart Quick Start Guide
32281S Quick Start Guide (this document)
42281S Precision DC Supply & Battery Simulator Product
Information CD-ROM
5Model CA-180-3A CAT5 Crossover Cable for Ethernet
6User's Guide Safety Standards Conformance Information
7 Cable housing

Connect the instrument
Important test system safety information
This product is sold as a stand-alone instrument that may become
part of a system that could contain hazardous voltagesand energy
sources. It is the responsibility of the test system designer, integrator,
installer, maintenance personnel, and service personnel to make sure
the system is safe during use and is operating properly.
You must also realize that in many test systems a single fault, such as
a software error, may output hazardous signal levels even when the
system indicates that there is no hazard present.
It is important that you consider the following factors in your system
design and use:
The international safety standard IEC 61010-1 defines voltages as
hazardous if they exceed 30 VRMS and 42.4 Vpeak, or 60 V DC for
equipment rated for dry locations. Keithley Instruments products
are only rated for dry locations.
Read and comply with the specifications of all instruments in the
system. The overall allowed signal levels may be constrained by
the lowest rated instrument in the system. For example, if you are
using a 500 V power supply with a 300 V DC rated switch, the
maximum allowed voltage in the system is 300 V DC.
Make sure any test fixture connected to the system protects the
operator from contact with hazardous voltages, hot surfaces, and
sharp objects. Use shields, barriers, insulation, and safety
interlocks to accomplish this.
Cover the device under test (DUT) to protect the operator from
flying debris in the event of a system or DUT failure.
Double-insulate all electrical connections that an operator can
touch. Double insulation ensures the operator is still protected
even if one insulation layer fails. Refer to IEC 61010-1 for
specific requirements.
Make sure all connections are behind a locked cabinet door or
other barrier. This protects the system operator from accidentally
removing a connection by hand and exposing hazardous voltages.
Use high-reliability fail-safe interlock switches to disconnect
power sources when a test fixture cover is opened.
Where possible, use automatic handlers so operators are not
required to access the DUT or other potentially hazardous areas.

Provide training to all users of the system so they understand all
potential hazards and know how to protect themselves from
injury.
In many systems, during power up, the outputs may be in an
unknown state until they are properly initialized. Make sure the
design can tolerate this situation without causing operator injury
or hardware damage.
To keep users safe, always read and follow all safety warnings
provided with each of the instruments in your system.
Install the instrument
You can use the 2281S on a bench or in a rack. Please see the
instructions that came with your rack-mount kit if you are installing
the 2281S in a rack.
To prevent damaging heat build-up and ensure specified
performance, make sure there is adequate ventilation and air flow
around the instrument to ensure proper cooling. Do not cover the
ventilation holes on the top, sides, or bottom of the instrument.
Make sure the instrument is positioned so that it is easy to reach any
disconnecting devices, such as the power cord and the power switch.
Power up the instrument
The 2281S operates at 100 V, 120 V, 220 V, or 240 V with a
frequency of 50 Hz or 60 Hz. Make sure that the AC line voltage
indicator in the center of the rear-panel power module matches the
AC line voltage in your facility. If it does not, refer to the
"Maintenance" section of the Model 2281 Reference Manual to change
the setting on the power entry module.

The power cord supplied with the 2281S contains a separate
protective earth (safety ground) wire for use with grounded outlets.
When proper connections are made, the instrument chassis is
connected to power-line ground through the ground wire in the
power cord. In addition, a redundant protective earth connection is
provided through a screw on the rear panel. This terminal should be
connected to a known protective earth. In the event of a failure, not
using a properly grounded protective earth and grounded outlet may
result in personal injury or death due to electric shock.
Do not replace detachable mains supply cords with inadequately
rated cords. Failure to use properly rated cords may result in
personal injury or death due to electric shock.
To connect line power:
1. Make sure the front panel power switch is in the off (0)
position.
2. Connect the socket of the supplied power cord to the power
module on the rear panel.
Operating the instrument on an incorrect line voltage may cause
damage to the instrument, possibly voiding the warranty.
3. Connect the plug of the power cord to a grounded AC outlet.
4. Turn on the instrument by pressing the front panel POWER
switch to the on (|) position. The instrument powers up.

Connections for testing
Before making the connections, prepare the wires as described in the
following table.
Usage
Specifications
Front panel binding posts
AWG 20 to AWG 12
Rear panel output terminals
AWG 20 to AWG 12
The wire must be heavy enough not to overheat while carrying
the short-circuit output current of the unit. Please meet the
wiring requirements described above.
Two-wire connection
Two-wire connections are used for basic operation when maximum
accuracy is not required. Keep the wire as short as possible to reduce
lead inductance and noise pickup. If you want to compensate for the
voltage drop in the load leads, use a four-wire sense connection.
When making two-wire connections with the 2281S, you must short
both Output Hi and Sense Hi and Output Lo and Sense Lo with the
shorting jumpers. If you do not do this, the display will show incorrect
voltage output readings.

Two-wire (local sensing) DUT connection to front panel Two-wire (local sensing) DUT connection to rear panel

After making the connections, slide the cable housing over the
output mating connector and wires.
Failure to install the cable housing may result in personal injury or
death due to electric shock.
Four-wire remote sense connection
Using four-wire remote sensing connections ensures that the
programmed voltage is applied to the load and compensates for the
voltage drop in the leads between the power supply and the load.
As shipped, the sense terminals are connected to the output terminals
by shorting jumpers. Before connecting the wire, make sure the
shorting jumpers have been removed. When you connect the power
supply for remote sensing, the overprotection (OVP) circuit senses
the voltage at the sensing points (load) and not the output terminals.
Four-wire (remote sensing) DUT connection to rear panel

After making the connections, slide the cable housing over the
output mating connector and wires.
Failure to install the cable housing may result in personal injury or
death due to electric shock.

Overview of the front-panel options
The front panel of the 2281S allows you to set up most instrument
functions and features and perform sourcing and measuring
operations. The front panel includes:
A high-resolution color display that allows you to access
instrument settings and measurement readings
Keys that select menu options and start measurement operations
A navigation control that can be used to select screen options
An output ON/OFF switch that turns the source output on or
off
Front-panel binding posts for output connections
ENTER and EXIT keys
The ENTER key selects a highlighted option. In most cases, it
opens the menu or dialog box that allows you to change settings for
that option.
The EXIT key returns to the previous menu or closes a dialog box.
For example, if you are in the Menu screen, pressing EXIT returns
you to the Home screen.
TRIGGER key
The action of the TRIGGER key depends on the trigger method
that is selected:
If manual triggering is selected, TRIGGER causes the instrument
to make a measurement.
If the trigger model is in idle, TRIGGER initiates the trigger
model.
Front-panel user interface overview
The front-panel user interface gives you quick access to source
settings, measure settings, system configuration, instrument status,
reading buffer information, and other instrument functionality.

Startup screen
When you turn on the 2281S, you will see the following startup
screen.
As you can see from the figure, 2281S has three functions:
High-precision power supply: Supplies 20 V, 6 A DC power
Battery test: Conducts battery charging and discharging test to
calculate the capacity and resistance of the battery and create a
battery model
Battery simulator: Simulates a battery to determine what effect
the battery has on the Device Under Test (DUT) in different
states
You can choose a function by turning the navigation control or
pressing the soft keys and pressing Enter to access the respective
home screens of the function.
Home screen overview
Home screen for power supply:
The above figure is the home screen 1 for the power supply function.
You can enter this screen by choosing the power supply function in
the startup screen. You can also visit other home screens by pressing
Next.

The top row on the Home screen displays the status and event
indicators. You can select these options to open dialog boxes that
provide additional information about the status or event.
The OUTPUT view area of the Home screen displays the value of
the present outputs and status indicators. The outputs show dashed
lines until the output is turned on.
The setting area of the Home screen is located in the lower left
corner of the OUTPUT view area. It shows the presently set measure
range, voltage, and current limit.
The soft-key area is located on the bottom of the Home screen. It
shows the present setting values. You can change these values by
pressing the buttons below the screen.

Home screen for battery test:
The above figure is the home screen 1 for the battery test function.
You can enter this screen by choosing the battery test function in the
startup screen. You can also visit other home screens by pressing
Next.
The top row on the Home screen displays the status and event
indicators. You can select these options to open dialog boxes that
provide additional information about the status or event.
The OUTPUT view area of the Home screen displays the values of
the battery under test.
The soft-key area is located on the bottom of the Home screen. It
shows the present setting values. You can change these values by
pressing the buttons below the screen.

Home screen for battery simulator:
The above figure is the home screen 1 for the battery simulation
function. You can enter this screen 1 by choosing the battery
simulation function in the startup screen. You can also visit other
home screens by pressing Next.
The top row on the Home screen displays the status and event
indicators. You can select these options to open dialog boxes that
provide additional information about the status or event.
The OUTPUT view area of the Home screen displays the values and
status of the battery simulator.
The soft-key area is located on the bottom of the Home screen. It
shows the present setting values. You can change these values by
pressing the buttons below the screen.

Menu screen overview
In any function, when you press the MENU key on the front panel,
the Menu screen is displayed. The following section uses the menu
for power supply as an example.
From this screen, you can select source, measure, graph, trigger, and
system setup menus. These menus allow you to choose options to set
up your instrument for your applications. Select a setup item by
either scrolling the navigation control or using the arrow keys to
highlight an icon. Then press ENTER.
An example of the options that are available when you select the
Settings option under Measure is shown below.