Keithley 182 User manual

Model 182 Sensitive Digital Voltmeter
Quick Reference Guide
A GREATER MEASURE OF CONFIDENCE

1
INTRODUCTION
This quick reference guide includes summary
information on front panel operation and IEEE-488
operationfortheModel182SensitiveDigitalVoltmeter.
Fordetailed Model 182 information,consult the Model
182 Instruction Manual.
©1990, Keithley Instruments, Inc.
All Rights Reserved
Cleveland, Ohio, U.S.A.
Document Number: 182-903-01 Rev. B

2
TABLE OF CONTENTS
SAFETY PRECAUTIONS ....................................... 3
CONTROL SUMMARY ........................................... 8
TEST CONNECTIONS ......................................... 14
DEVICE DEPENDENT COMMANDS ...................15
DATA FORMATS ................................................... 23
SRQ MASK AND SERIAL POLL BYTE................. 25
ALTERNATE OUTPUT WORD FORMATS ........... 26

3
SAFETY PRECAUTIONS
The following safety precautions should be observed
before using this product and any associated instru-
mentation. Although some instruments and accesso-
ries would normally be used with non-hazardous volt-
ages,thereare situations where hazardous conditions
may be present.
This product is intended for use by qualified person-
nelwho recognize shock hazards andare familiar with
the safety precautions required to avoid possible in-
jury. Read the operating information carefully before
using the product.
The types of product users are:
Responsible body is the individual or group respon-
sible for the use and maintenance of equipment, for
ensuring that the equipment is operated within its
specifications and operating limits, and for ensuring
that operators are adequately trained.
Operators use the product for its intended function.
They must be trained in electrical safety procedures
and proper use of the instrument. They must be pro-
tected from electric shock and contact with hazard-
ous live circuits.
Maintenancepersonnelperformroutineprocedureson
the product to keep it operating, for example, setting
the line voltage or replacing consumable materials.
Maintenanceproceduresare described in themanual.
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,
andperform safe installations andrepairs of products.

4
Only properly trained service personnel may perform
installation and service procedures.
Keithley products are designed for use with electrical
signals that are rated Installation Category I and In-
stallationCategory II, as describedin the International
Electrotechnical Commission (IEC) Standard IEC
60664. Most measurement, control, and data I/O sig-
nals are Installation Category I and must not be di-
rectlyconnectedtomainsvoltageortovoltagesources
withhightransientover-voltages. Installation Category
IIconnectionsrequireprotectionforhightransientover-
voltages often associated with local AC mains con-
nections. The user should assume all measurement,
control, and data I/O connections are for connection
to Category I sources unless otherwise marked or
described in the Manual.
Exercise extreme caution when a shock hazard is
present. Lethal voltage may be present on cable con-
nector jacks or test fixtures. The American National
Standards Institute (ANSI) states that a shock hazard
exists when voltage levels greater than 30V RMS,
42.4Vpeak,or60VDCarepresent.Agoodsafetyprac-
tice is to expect that hazardous voltage is present in
any unknown circuit before measuring.
Users of this product must be protected from electric
shock at all times. The responsible body must ensure
thatusers are prevented accessand/orinsulated from
every connection point. In some cases, connections
must be exposed to potential human contact. Product
users in these circumstances must be trained to pro-
tect 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.

5
Do not connect switching cards directly to unlimited
power circuits. They are intended to be used with im-
pedance limited sources. NEVER connect switching
cards directly toAC 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 re-
ceptacle. Inspect the connecting cables, test leads,
and jumpers for possible wear, cracks, or breaks be-
fore each use.
When installing equipment where access to the main
power cord is restricted, such as rack mounting, a
separate main input power disconnect device must
be provided, in close proximity to the equipment and
within easy reach of the operator.
For maximum safety, do not touch the product, test
cables, or any other instruments while power is ap-
plied to the circuit under test.ALWAYS remove power
fromthe entire testsystem and discharge anycapaci-
tors before: connecting or disconnecting cables or
jumpers, installing or removing switching cards, or
making internal changes, such as installing or remov-
ing 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 measure-
ments with dry hands while standing on a dry, insu-
lated surface capable of withstanding the voltage be-
ing measured.
The instrument and accessories must be used in ac-
cordancewith its specifications andoperating instruc-
tions or the safety of the equipment may be impaired.

6
Do not exceed the maximum signal levels of the in-
struments and accessories, as defined in the specifi-
cations and operating information, and as shown on
theinstrument or test fixturepanels, or switching card.
When fuses are used in a product, replace with same
type and rating for continued protection against fire
hazard.
Chassisconnections must only be usedas shield con-
nections 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 opera-
tion 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 documenta-
tion.
The symbol on an instrument indicates that the user
should refer to the operating instructions located in
the manual.
Thesymbol on aninstrument shows that it can source
or measure 1000 volts or more, including the com-
bined effect of normal and common mode voltages.
Use standard safety precautions to avoid personal
contact with these voltages.
TheWARNINGheading in a manualexplainsdangers
that might result in personal injury or death. Always
read the associated information very carefully before
performing the indicated procedure.
The CAUTION heading in a manual explains hazards
that could damage the instrument. Such damage may
invalidate the warranty.

7
Instrumentation and accessories shall not be con-
nected 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
thepowertransformer,testleads, 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 pur-
chasedfromother suppliers as long as theyareequiva-
lenttothe original component. (Note that selectedparts
shouldbepurchased only through Keithley Instruments
to maintain accuracy and functionality of the product.)
If you are unsure about the applicability of a replace-
mentcomponent, call aKeithley Instruments officefor
information.
Tocleananinstrument,usea 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. Prod-
uctsthatconsistofacircuitboardwithnocase or chas-
sis (e.g., data acquisition board for installation into a
computer) should never require cleaning if handled
according to instructions. If the board becomes con-
taminated and operation is affected, the board should
be returned to the factory for proper cleaning/servicing.

8
CONTROL SUMMARY
RANGE
Use UP and DOWN to manually select desired mea-
surement range; 3mV, 30mV, 300mV, 3V, or 30V.
Present range is displayed on status line.
PressAUTOtoturnauto-rangeonoroff.Unitupranges
atoverflowpoint (±3,029,999counts)anddownranges
at 9.33% of full range when AUTO is enabled.
Use FILTER to enable or disable both digital and ana-
log filters simultaneously (actual filter configuration or
response depends on MENU FILTER selections).
REL
Press REL READING to store current reading as
baseline. Subsequent readings will be the difference
between the applied signal and the stored baseline.
Press REL OUTPUT to store current analog output
value as analog output baseline. Analog output value
will be the difference between the normal, non-relative
output value and the stored analog output baseline.
TRIG
Press SETUP to program TRIGGER MODE, TRIG-
GER SOURCE, TRIGGER DELAY, AND TRIGGER
INTERVAL.

9
Use ▲or ▼to scroll through selections, ENTER to
select, or ESC to cancel selection.
TRIGGERMODE:selectmultiple(continu-
ouswithone trigger) or one-shot(oneread-
ing per trigger).
TRIGGER SOURCE: select external,
manual, disabled, or IEEE-488 X, GET or
talk triggers.
TRIGGER DELAY: program desired trig-
ger delay (time between trigger and read-
ing in one-shot trigger mode): 0sec-
999.999sec.
TRIGGER INTERVAL: program desired
trigger interval (time between individual
readings in multiple trigger mode): 0.01
sec-999.999sec.
BUFFER
Use STORE to start/stop buffer data storage. Store
sizeof1-1024selects linear buffer(storagestopswhen
size limitation is reached); store size of 0 selects cir-
cular buffer (buffer wraps around and overwrites old
dataafter 1024 readings arestored). Unit stores read-
ings at programmed trigger interval in multiple trigger
mode or one reading per trigger in one-shot trigger
mode.
Press RECALL to access stored buffer readings and
buffer statistics. Readings include buffer location and
time stamp. Statistics include number of samples,
buffer average, maximum, minimum, and standard
deviation.