Hioki DM7275 Series User manual

EN
Instruction Manual
DM7276
PRECISION DC VOLTMETER
DM7275
Dec. 2016 Edition 1
DM7275A961-00 16-12H
DM7275-01
DM7275-02
DM7275-03
DM7276-01
DM7276-02
DM7276-03
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Measurement process
Measurement process
This section describes voltage measurement as performed in a typical application.
Example use: Measuring a battery’s voltage
Preparations
(1) Position the instrument as desired. (p. 7)
50 mm or more 50 mm or more 150 mm or more
Rear
(2) Perform the pre-measurement inspection. (p. 24)
(3) Connect the power cord. (p. 25)
(4) Connect the measurement cables to the measurement terminals. (p. 26)
(5) Connect the temperature sensor to the TEMP.SENSOR connector.
(When performing temperature measurement or using the temperature compensation) (p. 27)
(6) Congureandconnecttheexternalinterface(asnecessary).
• Using the USB interface (p. 98)
• Using the RS-232C interface (p. 100)
• Using the GP-IB interface (p. 102)
• Using the LAN interface (p. 104)
• Using a USB ash drive (p. 115)
• Using the EXT I/O connector (p. 125)
DM7275A961-00
Power cord To outlet
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付録索引
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Measurement process
(7) Turn on the instrument. (p. 28)
(8) Set the time and date. (p. 30)
Measurement
(9) Set the measurement range. (p. 35) (default setting: AUTO range)
When using the auto-range setting, the instrument will automatically select the optimal range.
To x the range manually: Manual range (p. 35)
(10)Set the measurement speed. (p. 35) (default setting: MEDIUM)
(11) Switchthemeasuredvaluedisplay.(p. 18) (default setting: V)
(12) Connect the measurement cables to the measurement target. (p. 31)
Black Red
(13) Perform measurement. (p. 37)
• To enable the trend display (time-axis display) or to display judgment results: (p. 43)
• To display information other than measured values (error display): (p. 46), (p. 176)
• To assign names to measured values: (p. 49)
• To hold the measured value display: (p. 37), (p. 70)
• To change the number of display digits: (p. 48)
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Contents
iii
3.5 MeasurementErrorDisplays
(DisplaysOtherThanMeasured
Values)............................................. 46
Measurement error detection order............47
3.6 ChangingtheNumberofDisplay
Digits ............................................... 48
3.7 DisplayingLabels(Assigning
Names to Measured Values).......... 49
4 Judging Measured
Values 51
4.1 ToObtainAccurateJudgments
EvenWhenthePolarityofthe
MeasurementTarget(Battery,
etc.) Is Reversed............................. 52
4.2 ComparatorMeasurement
(Using a Single Judgment
Standard) ........................................ 53
To check judgments aurally ........................55
To perform judgment after measured
values stabilize ...........................................56
To output judgment results to an
external device or to print judgment results 56
4.3 BINMeasurement(Using
Multiple Judgment Standards)...... 57
To output judgment results to an
external device or to print judgment results 59
5 SavingandLoading
Measurement
Conditions (Internal
Memory) 61
5.1 SavingMeasurementConditions
(Panel Save Function).................... 62
5.2 LoadingMeasurement
Conditions(PanelLoadFunction) 64
5.3 ChangingthePanelName............. 65
5.4 DeletingaPanel ............................. 66
6 UsefulFunctionality 67
6.1 ObtainingStableMeasured
Values.............................................. 67
Setting the integration time.........................67
Reducing measured value variability
(smoothing function) ...................................69
6.2 Auto-holdFunction ........................ 70
6.3 ContactCheck ................................ 71
6.4 SwitchingtheInputResistance .... 76
Introduction................................................ 1
VerifyingPackageContents ..................... 2
SafetyInformation..................................... 5
Operating Precautions.............................. 7
1 Overview 13
1.1 Product Overview........................... 13
1.2 Features .......................................... 13
1.3 Part Names and Functions............ 14
1.4 ScreenLayout ................................ 16
1.5 OperatingtheInstrument .............. 17
Changing settings.......................................17
Returning to the previous screen................17
Switching the measured value display........18
Changing the range....................................18
Changing the measurement speed.............19
Starting measurement ................................20
1.6 HowtoUseThisManual................ 21
2 Preparing for
Measurement 23
2.1 Preparation Process ...................... 23
2.2 Performing the Pre-
measurement Inspection............... 24
2.3 Connecting the Power Cord.......... 25
2.4 ConnectingtheMeasurement
Cables (to the Instrument)............. 26
2.5 ConnectingtheTemperature
Sensor............................................. 27
2.6 TurningtheInstrumentOnand
Off.................................................... 28
2.7 SettingtheTimeandDate ............. 30
3 Measurement 31
3.1 Connecting the Measurement
Cables (Measurement Target)....... 31
3.2 Setting the Measurement Range .. 35
3.3 Setting the Measurement Speed... 36
3.4 StartingMeasurement ................... 37
Continuous measurement...........................37
Trigger measurement (measurement
with user-specied timing) ..........................38
Storage of measurement data in the
instrument’s internal memory......................42
Displaying trends, bar graphs, statistics,
and judgment results ..................................43
Checking the voltage trend.........................45
Contents
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Ind. Ind.
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Contents
iv
6.5 CorrectingMeasuredValues......... 77
Adjusting the zero-point (NULL function)....78
Compensating the effects of temperature
(temperature
compensation function)..........80
Correcting measured values using a
linear expression (scaling function) ............82
6.6 StatisticalCalculations.................. 84
Displaying, clearing, and printing
statistical calculation results .......................85
7 SystemSettings 87
7.1 KeyLock(DisablingInstrument
Operation)....................................... 87
7.2 BuzzerSettings .............................. 88
7.3 AdjustingtheScreenBrightness . 89
7.4 ChangingtheScreenColor........... 89
7.5 AdjustingtheTouchPanel
Position........................................... 90
7.6 SettingthePowerSupply
Frequency ....................................... 90
7.7 SelectingStartupLoadSettings
and a Panel ..................................... 91
7.8 SettingOutputFormats ................. 92
7.9 ResettingtheInstrument
(Reverting the Instrument to Its
FactorySettings)............................ 93
List of default settings.................................94
8 PreparingtoUseUSB,
RS-232C,GP-IB,and
LANControl 97
8.1 OverviewofInterfacesand
Associated Features...................... 97
8.2 PreparingtoUseanInterface
(Connection and Settings) ............ 98
Using the USB interface .............................98
Using the RS-232C interface....................100
Using the GP-IB interface.........................102
Using the LAN interface............................104
8.3 CommunicationsSettings........... 109
Communications monitor (displaying
communications commands) ....................109
Setting the format for measurement.........110
Setting the model name acquired by
commands................................................110
9 Outputting Data 111
9.1 Interface Settings..........................111
9.2 Output Methods.............................112
9.3 Data Output Settings ....................113
10 Using a USB Flash
Drive 115
10.1 Overview ........................................115
10.2 ConnectingaUSBFlashDrive ....116
10.3 SettingtheInterface......................117
10.4 SettingtheOutputDataType .......117
10.5 OutputtingData(USBFlash
Drive)..............................................118
Outputting measurement data or
screenshots ..............................................118
Outputting all measurement data..............119
10.6 OutputtingandLoading
Measurement Conditions (USB
Flash Drive)................................... 120
Outputting measurement conditions.........120
Loading measurement conditions.............122
10.7 Files ............................................... 123
File format.................................................123
11 ExternalControl(EXTI/
O) 125
11.1 ExternalControlMeasurement
Process ......................................... 125
11.2 SwitchingbetweenCurrentSink
(NPN) and Current Source (PNP) 126
11.3 Connections (Instrument and
Control Device)............................. 127
Instrument connector and compatible
connectors................................................128
Signal functions ........................................129
Internal circuit architecture........................133
Electrical specications.............................134
Example connections................................134
11.4 ConguringExternalInputand
Output ........................................... 136
Input lter ..................................................136
EOM signal output type ............................137
11.5 InputTest/OutputTest ................. 138
11.6 TimingChart ................................. 139
Timing from the start of measurement to
acquisition of judgment results .................139
Panel load timing......................................141
Output signal status when the
instrument is turned on.............................142
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Contents
v
Measurement process (starting
measurement from an external device
and loading judgment results)...................142
12 Printing 143
12.1 Printer Settings ............................ 144
12.2 Connecting the Printer to the
Instrument..................................... 146
12.3 ConguringtheInstrument......... 146
12.4 Printing.......................................... 147
Print examples..........................................148
13 Specications 151
13.1 GeneralSpecications ................ 151
13.2 MeasurementSpecications....... 152
Basic specications ..................................152
Accuracy specications ............................155
13.3 FunctionalSpecications............ 157
13.4 InterfaceSpecications............... 163
14 Maintenance and
Service 167
Calibration and repair ...............................167
Transporting the instrument......................167
Replacement parts and their service lives167
14.1 Q&A(FrequentlyAsked
Questions) .................................... 168
1. General issues......................................168
2. Measurements......................................169
3. Communications...................................171
4. EXT I/O .................................................173
Frequently Asked Questions for External
Control (EXT I/O) ......................................175
14.2 Cleaning ........................................ 175
14.3 ErrorDisplays............................... 176
14.4 DisposingoftheInstrument ....... 180
15 LicenseInformation 181
Appendix Appx.1
Appx.1 BlockDiagram.................. Appx.1
Appx.2 MeasuringtheEnclosure
PotentialofLaminated
Lithium-ionBatteries....... Appx.2
Internal insulation defects in lithium-ion
batteries...............................................Appx.2
Enclosure potential measurement.......Appx.3
Appx.3 CausesofErrorin
Voltage Measurement...... Appx.5
Thermal electromotive force................Appx.5
Effects of input resistance....................Appx.6
Effects of bias current..........................Appx.6
Effects of high-voltage measurement..Appx.7
Effects of burst noise...........................Appx.7
Appx.4 NoiseCountermeasures . Appx.8
Effects of induced noise.......................Appx.8
Effects of conductive noise................Appx.10
Appx.5 Self-calibration................Appx.11
Appx.6 MeasuringMultiple
Targets............................ Appx.12
Appx.7 RackMounting ............... Appx.14
Rack-mounting hardware reference
gures ................................................Appx.14
Installation instructions ......................Appx.17
Appx.8 OutlineDrawings ........... Appx.21
Appx.9 Calibration ...................... Appx.22
Appx.10Adjustment ..................... Appx.23
Index Ind.1
Appx.
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1
Introduction
Introduction
Thank you for purchasing the Hioki DM7275, DM7276 Precision DC Voltmeter. To obtain maximum
performance from the instrument, please read this manual rst, and keep it handy for future
reference.
Model Interface
DM7275 DM7276 LAN USB GP-IB RS-232C
DM7275-01 DM7276-01   - -
DM7275-02 DM7276-02  -
DM7275-03 DM7276-03   -
: Available, −: Not available
Registeredtrademarks
• Microsoft, Windows 7 and Windows 8 are either registered trademarks or trademarks of Microsoft
Corporation in the United States and other countries.
• Teon is a registered trademark of E. I. du Pont de Nemours and Company.
Notations
*Additional information is presented below.
SET
(bold) Names and keys on the screen are indicated with bold characters.
[ ] Operation keys are indicate in []square brackets.
Unless otherwise specied, “Windows” represents Windows 7 and Windows 8.
Accuracy
We dene measurement tolerances in terms of f.s. (full scale), rdg. (reading) and dgt. (digit) values,
with the following meanings:
f.s. (Maximum display)
The maximum displayable value.
rdg. (Reading)
The value currently being measured and indicated on the measuring instrument.
dgt. (Resolution) The smallest displayable unit on a digital measuring instrument, i.e., the input value that
causes the digital display to show a "1" as the least-signicant digit.
See “Accuracy specications” (p. 155).
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2
Verifying Package Contents
VerifyingPackageContents
• When you receive the instrument, inspect it carefully to ensure that no damage occurred during
shipping. In particular, check the accessories, panel switches, buttons, keys and connectors. If
damage is evident, or if it fails to operate according to the specications, contact your authorized
Hioki distributor or reseller.
• Store the packaging in which the instrument was delivered, as you will need it when transporting
the instrument.
Check if the package contents are correct.
DM7275 or DM7276
Accessories
Application disc (CD)
(Communication Command
Instruction Manual (PDF) and USB
Driver are included)
• The latest version can be
downloaded from our web site.
Power supply cord Instruction manual
(this document)
Instruction manuals may
also be available in other
languages.
Please visit our website at
http://www.hioki.com.
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3
Verifying Package Contents
Options(SoldSeparately)
The following options are available for the instrument. Contact your authorized Hioki distributor or
reseller when ordering.
Measurement cables (general voltage measurements)
9243 graber L4937 マグネットアダプ
タ
L4934 小ワニグチ
マグネ付ストラップ
L9207-10
DM4910 熱電対
DT4911TestLead
DT4912TestLead
L4930 接続ケーブル
L4931renketu
L4931 延長ケーブル
L4932(+9207-10cap)
L4933 コンタクトピン
L4935 ワニ口
L4936 バスバー
9243 graber L4937 マグネットアダプ
タ
L4934 小ワニグチ
マグネ付ストラップ
L9207-10
DM4910 熱電対
DT4911TestLead
DT4912TestLead
L4930 接続ケーブル
L4931renketu
L4931 延長ケーブル
L4932(+9207-10cap)
L4933 コンタクトピン
L4935 ワニ口
L4936 バスバー
9243 graber L4937 マグネットアダプ
タ
L4934 小ワニグチ
マグネ付ストラップ
L9207-10
DM4910 熱電対
DT4911TestLead
DT4912TestLead
L4930 接続ケーブル
L4931renketu
L4931 延長ケーブル
L4932(+9207-10cap)
L4933 コンタクトピン
L4935 ワニ口
L4936 バスバー
9243 graber L4937 マグネットアダプ
タ
L4934 小ワニグチ
マグネ付ストラップ
L9207-10
DM4910 熱電対
DT4911TestLead
DT4912TestLead
L4930 接続ケーブル
L4931renketu
L4931 延長ケーブル
L4932(+9207-10cap)
L4933 コンタクトピン
L4935 ワニ口
L4936 バスバー
9243 graber L4937 マグネットアダプ
タ
L4934 小ワニグチ
マグネ付ストラップ
L9207-10
DM4910 熱電対
DT4911TestLead
DT4912TestLead
L4930 接続ケーブル
L4931renketu
L4931 延長ケーブル
L4932(+9207-10cap)
L4933 コンタクトピン
L4935 ワニ口
L4936 バスバー
9243 graber L4937 マグネットアダプ
タ
L4934 小ワニグチ
マグネ付ストラップ
L9207-10
DM4910 熱電対
DT4911TestLead
DT4912TestLead
L4930 接続ケーブル
L4931renketu
L4931 延長ケーブル
L4932(+9207-10cap)
L4933 コンタクトピン
L4935 ワニ口
L4936 バスバー
9243 graber L4937 マグネットアダプ
タ
L4934 小ワニグチ
マグネ付ストラップ
L9207-10
DM4910 熱電対
DT4911TestLead
DT4912TestLead
L4930 接続ケーブル
L4931renketu
L4931 延長ケーブル
L4932(+9207-10cap)
L4933 コンタクトピン
L4935 ワニ口
L4936 バスバー
9243 graber L4937 マグネットアダプ
タ
L4934 小ワニグチ
マグネ付ストラップ
L9207-10
DM4910 熱電対
DT4911TestLead
DT4912TestLead
L4930 接続ケーブル
L4931renketu
L4931 延長ケーブル
L4932(+9207-10cap)
L4933 コンタクトピン
L4935 ワニ口
L4936 バスバー
9243 graber L4937 マグネットアダプ
タ
L4934 小ワニグチ
マグネ付ストラップ
L9207-10
DM4910 熱電対
DT4911TestLead
DT4912TestLead
L4930 接続ケーブル
L4931renketu
L4931 延長ケーブル
L4932(+9207-10cap)
L4933 コンタクトピン
L4935 ワニ口
L4936 バスバー
L4933
Contact Pin Set
Pin diameter: φ1 mm
L4934
Small Alligator Clip Set
Maximum clip width:
φ4 mm
L4935
Alligator Clip Set
Maximum clip width:
φ25 mm
9243
GrabberClip
Maximum clip width:
φ2 mm
L4936
Bus Bar Clip Set
Maximum clip width:
φ25 mm
(Objects to be measured
which are 30 mm or less
can be clipped.)
L4932
Test Pin Set
Pin diameter: φ2 mm
L9207-10
TestLead
Pin diameter: φ2 mm
L4930
Connection Cable Set
Length: 1.2 m
L4931
ExtensionCableSet
Length: 1.5 m
With coupling connector
Measurement cable Safetyextra-low
voltage CATII* CATIII* CATIV*
L9207-10, L4932 -1000 V 1000 V 600 V
L4930, L4931, L4935 - - 1000 V 600 V
L4933 33 V AC/70 V DC ---
L4934 -600 V 300 V -
9243 - - 1000 V -
L4936 - - 600 V -
*: Measurements over measuring instrument's rated voltage are not possible.
See “Inspection before use” (p. 7)
Temperature measurements
Z2001 Temperature Sensor
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Appx. Ind.
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4
Verifying Package Contents
Communication interface
9637 RS-232C Cable 9 pins-9 pins/1.8 m/cross
9151-02 GP-IB Connector Cable 2 m
L1002 USB Cable (A - B) A-B type
9642 LAN Cable
For printing
9442 Printer
9443-01 AC Adapter For Japan
9443-02 AC Adapter For countries other than Japan
1196 Recording Paper
9444 Connection Cable To connect the instrument and
the 9442 printer
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5
Safety Information
SafetyInformation
This instrument is designed to conform to IEC 61010 Safety Standards, and has been thoroughly
tested for safety prior to shipment. However, using the instrument in a way not described in this
manual may negate the provided safety features.
Before using the instrument, be certain to carefully read the following safety notes.
DANGER
Mishandlingduringusecouldresultininjuryordeath,aswellasdamagetothe
instrument.Becertainthatyouunderstandtheinstructionsandprecautionsin
the manual before use.
WARNING
•Withregardtotheelectricitysupply,therearerisksofelectricshock,heat
generation,re,andarcdischargeduetoshortcircuits.Ifpersonsunfamiliar
withelectricitymeasuringinstrumentaretousetheinstrument,anotherperson
familiar with such instruments must supervise operations.
•Thisinstrumentismeasuredonaliveline.Toavoidelectricshockwhen
measuringlivelines,wearappropriateprotectivegear,suchasinsulatedrubber
gloves,bootsandasafetyhelmet.
Notations
In this manual, the risk seriousness and the hazard levels are classied as follows.
DANGER Indicates an imminent hazardous situation that will result in death or serious injury to
the operator.
WARNING Indicates a potentially hazardous situation that may result in death or serious injury to
the operator.
CAUTION Indicates a potentially hazardous situation that may result in minor or moderate injury
to the operator or damage to the instrument or a malfunction.
IMPORTANT Indicates information related to the operation of the instrument or maintenance tasks
with which the operators must be fully familiar.
Indicates a high voltage hazard.
If a particular safety check is not performed or the instrument is mishandled, this may
give rise to a hazardous situation; the operator may receive an electric shock, may get
burnt or may even be fatally injured.
Indicates a prohibited action.
Indicates the action which must be performed.
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3
2
1
Appx. Ind.
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6
Safety Information
Symbolsontheinstrument
Indicates cautions and hazards.
When the symbol is printed on the
instrument, refer to a corresponding
topic in the Instruction Manual.
Indicates a grounding terminal.
Indicates DC (Direct Current).
Indicates AC (Alternating Current).
Indicates the ON side of the power
switch.
Indicates the OFF side of the power
switch.
Symbolsforstandards
Indicates the Waste Electrical and
Electronic Equipment Directive
(WEEE Directive) in EU member
states.
Indicates that the product conforms
to regulations set out by the EC
Directive.
Measurement categories
To ensure safe operation of measuring instruments, IEC 61010 establishes safety standards
for various electrical environments, categorized as CAT II to CAT IV, and called measurement
categories.
DANGER
•Using a measuring instrument in an environment designated with a higher-
numberedcategorythanthatforwhichtheinstrumentisratedcouldresultina
severeaccident,andmustbecarefullyavoided.
•Using a measuring instrument without categories in an environment designated
withtheCATIItoCATIVcategorycouldresultinasevereaccident,andmust
becarefullyavoided.
This instrument conforms to the safety requirements for CAT II 300 V measuring instruments.
CAT II: When directly measuring the electrical outlet receptacles of the primary electrical
circuits in equipment connected to an AC electrical outlet by a power cord (portable
tools, household appliances, etc.).
CAT III: When measuring the primary electrical circuits of heavy equipment (xed installations)
connected directly to the distribution panel, and feeders from the distribution panel to
outlets.
CAT IV: When measuring the circuit from the service drop to the service entrance, and to the
power meter and primary overcurrent protection device (distribution panel).
T
Outlet
CAT II
Internal wiring
Distribution panel
Service entrance
Service drop
CAT IV
Power meter
CAT III
Fixed installation
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7
Operating Precautions
Operating Precautions
Follow these precautions to ensure safe operation and to obtain the full benets of the various
functions.
Inspection before use
WARNING
Ifthemeasurementcableortheinstrumentisdamaged,thereisariskofelectric
shock.Beforeusingtheinstrumentperformthefollowinginspection.
•Beforeusingtheinstrument,makesurethattheinsulationonthecablesare
undamagedandthatnobareconductorsareimproperlyexposed.Usingthe
instrumentundersuchconditionscouldresultinelectricshock.Replacethe
cablewiththosespeciedbyourcompany.
•Topreventanelectricshock,conrmthatthewhiteportion(insulationlayer)
insidethecableisnotexposed.Ifacolorinsidethecableisexposed,donot
use the cable.
•Beforeusingtheinstrumentforthersttime,verifythatitoperatesnormally
toensurethatnodamageoccurredduringstorageorshipping.Ifyoundany
damage,contactyourauthorizedHiokidistributororreseller.
Installation environment
WARNING
Installingtheinstrumentininappropriatelocationsmaycauseamalfunctionof
instrumentormaygiverisetoanaccident.Avoidthefollowinglocations.
•Exposedtodirectsunlightorhightemperature
•Exposedtocorrosiveorcombustiblegases
•Exposedtoastrongelectromagneticeldorelectrostaticcharge
•Nearinductionheatingsystems(suchashigh-frequencyinductionheating
systemsandIHcookingequipment)
•Susceptible to vibration
•Exposedtowater,oil,chemicals,orsolvents
•Exposedtohighhumidityorcondensation
•Exposedtohighquantitiesofdustparticles
10
9
8
7
6
5
4
3
2
1
Appx. Ind.
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8
Operating Precautions
Installation method
CAUTION
Do not place the instrument on an unstable table or an inclined place. Dropping or
knocking down the instrument can cause injury or damage to the instrument.
• Install the instrument with the bottom facing down.
• To prevent overheating, be sure to leave the specied clearances around the instrument.
50 mm or more 50 mm or more 150 mm or more
Rear
The stand can be used to lift the instrument's front panel. (p. 14)
The instrument can also be mounted on racks.
（p. Appx.14）
Unplugging the power cord kills power to the instrument. Be sure to provide enough unobstructed
space to unplug the power cord immediately in an emergency.
Handlingtheinstrument
DANGER
Toavoidelectricshock,donotremovetheinstrument'scase.Theinternal
componentsoftheinstrumentcarryhighvoltagesandmaybecomeveryhot
during operation.
CAUTION
To avoid damage to the instrument, protect it from physical shock when transporting
and handling. Be especially careful to avoid physical shock from dropping.
This instrument may cause interference if used in residential areas. Such use must be avoided
unless the user takes special measures to reduce electromagnetic emissions to prevent
interference to the reception of radio and television broadcasts.
Precautions when using the included application disc
• Exercise care to keep the recorded side of discs free of dirt and scratches. When writing text on a
disc’s label, use a pen or marker with a soft tip.
• Keep discs inside a protective case and do not expose to direct sunlight, high temperature, or
high humidity.
• Hioki is not liable for any issues your computer system experiences in the course of using this
disc.
Before connecting a power cord
WARNING
Toavoidelectricalaccidentsandtomaintainthesafetyspecicationsofthis
instrument,connectthepowercordprovidedonlytoanoutlet.
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9
Operating Precautions
Before connecting a measurement cable
DANGER
Measurementcablesshouldonlybeconnectedtothesecondarysideofa
breaker.Anyshort-circuitcurrentatthesecondarysidewillbecut-offbythe
breaker.Connectionsshouldneverbemadetotheprimarysideofabreaker,
becauseunrestrictedcurrentowcoulddamagetheinstrumentandfacilitiesifa
short circuit occurs.
WARNING
To avoid electric shock and short-circuit accidents, use only the specied measurement
cables to connect the instrument input terminals (HIGH and LOW terminals) to the
circuit over 70 V DC to be tested.
Before connecting a temperature sensor
IMPORTANT
Connect the temperature sensor by inserting the plug all the way in the TEMP.SENSOR
connector. Insufcient connection may cause larger errors in measured values.
Before turning the power ON
WARNING
Beforeturningtheinstrumenton,makesurethesupplyvoltagematchesthat
indicatedonitspowerconnector.Connectiontoanimpropersupplyvoltagemay
damagetheinstrumentandpresentanelectricalhazard.
CAUTION
Avoid using an uninterruptible power supply (UPS) or DC/AC inverter with rectangular
wave or pseudo-sine-wave output to power the instrument. Doing so may damage the
instrument.
10
9
8
7
6
5
4
3
2
1
Appx. Ind.
www. .com [e-mail]1.800.561.8187

10
Operating Precautions
Before starting a measurement
Voltage measurements
DANGER
•Themaximumratedvoltagebetweeninputterminalsandthegroundisas
follows.
CATII:300VAC/DC
Nomeasurementcategory:800VAC/DC
Iftheirvoltagesareexceeded,thisinstrumentwillbedamagedandpersonal
injurywillresult.Therefore,donotperformmeasurementinthiscase.
•Maximuminputvoltageofthevoltagemeasurementterminalsis1000VDC,
105VHzAC,1500Vpeak.However,voltagesover800Vcanbemeasuredonly
if the circuit to be measured is isolated from the ground. If their voltages are
exceeded,thisinstrumentwillbedamagedandpersonalinjurywillresult.
Therefore,donotperformmeasurementinthiscase.
•Toavoidelectricshock,becarefultoavoidshortinglivelineswiththe
measurement cables.
Temperature measurements
CAUTION
• To avoid damage to the instrument, do not apply voltage to TEMP.SENSOR
connector.
• Temperature sensors are not waterproof. Do not soak the sensor in water.
IMPORTANT
• The object to be measured for temperature compensation and the temperature sensor
should be given adequate time to adapt to the ambient temperature. If lesser time is given for
adaptation to ambient temperature may cause larger errors.
• Handling temperature sensors with bare hands may cause induction noise resulting in unstable
measured values.
• Temperature sensors are used to measure ambient temperature. Temperature sensors on the
surface of the object to be measured cannot measure correct temperature of the object itself.
If there is a large difference in temperature between the ambient temperature and temperature
of the object to be measured, use an aluminum tape to attach the temperature sensor onto the
object while ensuring that the object is not short-circuited.
Before connecting the communicationcables(USB,LAN,RS-232C,GP-IB)
CAUTION
Before connecting or disconnecting any communications cable, always turn off the
instrument and equipment to be connected with. This may cause malfunction or
damage.
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11
Operating Precautions
BeforemakingaconnectiontotheUSBconnector
CAUTION
• To avoid equipment failure, do not disconnect the USB cable while communications
are in progress.
• Use a common ground for both the instrument and the computer. Use of different
ground circuits will result in a potential difference between the instrument's ground
and the computer's ground. If the USB cable is connected while such a potential
difference exists, it may result in equipment malfunction or failure.
BeforeconnectingtotheRS-232CorGP-IBconnectors
CAUTION
• Use a common ground for the instrument, computer and programmable controller.
Use of different ground circuits will result in a potential difference between the
instrument's ground and grounds of the computer and programmable controller. If the
communications cable is connected while such a potential difference exists, it may
result in equipment malfunction or failure.
• After connecting the communications cable, tighten the screws on the connector
securely. Failure to secure the connector could result in equipment malfunction or
damage.
BeforeconnectingaUSBashdrive
CAUTION
• Inserting a USB ash drive upside down, backwards or in the wrong direction may
damage the USB ash drive or the instrument.
• Some USB ash drives are susceptible to static electricity. Exercise care when using
such products because static electricity could damage the USB ash drive or cause
malfunction of the instrument.
With some USB ash drives, the instrument may not start up if power is turned on while the USB
ash drive is inserted. In such a case, turn power on rst, and then insert the USB ash drive.
It is recommended to try out operation with a USB ash drive before starting to use it for actual
measurements.
Beforeswitchingthecurrentsink(NPN)/currentsource(PNP)
CAUTION
• Never switch between NPN and PNP while the instrument's power is on.
• Congure the NPN/PNP setting based on the externally connected device.
10
9
8
7
6
5
4
3
2
1
Appx. Ind.
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12
Operating Precautions
BeforeconnectingtotheEXTI/Oconnector
WARNING
Toavoidelectricshockordamagetotheequipment,alwaysobservethefollowing
precautionswhenconnectingtoEXTI/Oconnector.
•Alwaysturnoffthepowertotheinstrumentandtoanydevicestobeconnected
beforemakingconnections.
•BecarefultoavoidexceedingtheratingofEXTI/Oconnectorsignal.
Before connecting a printer
WARNING
Toavoidelectricshock,turnoffthepowertoalldevicesbeforepluggingor
unplugginganycablebetweentheprinterandtheinstrument.
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13
1Overview
1.1 Product Overview
The Hioki DM7275 and DM7276 Precision DC Voltmeters can measure DC voltages from lithium-
ion batteries, electric double-layer capacitors, and other components as well as DC voltages output
by sensors and other devices with a high degree of accuracy.
1.2 Features
High-accuracymeasurement
The DM7275 and DM7276 deliver the following basic accuracy (in the 10 V range):
DM7275 0.0020% rdg. +12 µV
DM7276 0.0009% rdg. +12 µV
The DM7276 can measure a 4 V lithium-ion battery with accuracy of 48 µV.
Contactcheckfunction
When this function is enabled, measured values are displayed only when the measurement cables
are properly connected to the measurement target. It is particularly useful as a way to ensure highly
reliable results when measuring the potential on the exterior of a lithium-ion battery.
Temperature compensation
In addition to DC voltage, the DM7275/DM7276 can measure ambient temperature. When
measuring a target that exhibits a high degree of temperature dependency, this function corrects
voltage measured values using the measured temperature, making it possible to convert them to to
voltage values at a reference temperature.
High-speedmeasurementandmeasuredvaluememory
The DM7275/DM7276 can continuously save data to its 5000 data point internal memory at speeds
of up to 1 ms. This capability can be used to monitor instantaneous voltage uctuations or measure
multiple targets.
Extensiveinterfaceoptions
The DM7275/DM7276 provides USB, LAN, RS-232C*, GP-IB*, and EXT I/O interfaces, enabling its
use in a variety of applications.
*These interfaces are factory options that must be specied at the time of shipment.
Intuitive user interface
The DM7275/DM7276 has a 4.3” color LCD and an intuitive, touch-panel based user interface. It
also provides extensive analytical functionality, including statistical calculations and trend plots.
Smooth integration into production lines
• Since the DM7275/DM7276’s free power supply specications can accommodate a power supply
from 100 to 240 V, it can be easily deployed on production lines overseas.
• The instrument’s communications monitor and EXT I/O test functions facilitate smooth debugging
of testing systems.
• Judgment functions can be used to generate PASS/FAIL judgments based on the classication of
measurement results into HI, IN, and LO categories (comparator function) or to rank targets into
up to 10 categories (BIN function).
1 Overview
1
Overview
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14
Part Names and Functions
1.3 Part Names and Functions
Front 1
2
3
4
5
1Display
(Touch panel) Viewmeasuredvalues,settings,andjudgmentresults;congureinstrumentsettings.
• Display the Settings screen and Measurement screen (measured values and judgment
results) (p. 16).
• Congure settings (p. 17).
2 Operation
keys For more information: See “1.5OperatingtheInstrument”(p. 17).
[V/°C]key Toggles display of
temperature measured
values.
[AUTO]key Enables auto-range
operation (to automatically
select an appropriate range).
[NULL]key Adjusts the instrument’s
zero-point. [RANGE] []key Increases the range (to measure high voltages).
[RUN/STOP]
key Starts and stops measurement. []key Decreases the range (to
measure at a higher degree
of resolution).
[TRIG]key Starts measurement (to
make measurements at
the desired timing).
[SPEED]key Changes the measurement
speed.
3 POWER
button
(p. 28)
Switches the instrument’s
power state. OFF: The instrument is off (no power is being supplied).
RED: The instrument is in the SLEEP state (power is
being supplied).
GREEN: The instrument is on.
4
USBashdrive
connector
Outputsmeasurementdata,screendata,andmeasurementconditions;loads
measurement conditions (p. 115).
5Voltage
measurement
terminals
Connect the measurement
cables (p. 26).HIGH terminal: Connect the red cable.
LOW terminal: Connect the black cable.
See “Before connecting a measurement cable”(p. 9).
Bottom
Foot
Foot
Whenmountingtheinstrumentinarack
Be sure to collapse the feet all the way.
See: “Appx. 7 Rack Mounting” (p. Appx.14)
When using the feet
Be sure to:
• Open the feet all the way, without stopping partway.
• Erect both feet.
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