Extech Instruments GX930 User manual

USERGUIDE

MODELGX900–GRAPHICALDMM
MODELGX930–DMM/DIGITALOSCILLOSCOPE

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2 GX900-GX930-EN V1.1 5/14
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INTRODUCTION
ThankyouforselectingtheExtechModelGX900TrueRMSDigitalMultimeteror
GX930TrueRMSDigitalMultimeterwithDigitalOscilloscope.Thesedevicesare
shippedfullytestedandcalibratedand,withproperuse,willprovideyearsof
reliableservice.ExtechInstrumentsisanISO‐9001certifiedcompany.
GX900‐KEYFEATURES
TheGX900measuresAC/DCVoltage/Current(includingremoteClamp
current),Resistance,Capacitance,Frequency(electricalandelectronic),
RPM,DutyCycle,dBm/dBV,Diode,Continuity,andTemperature
TheGX930DMMmeasuresAC/DCVoltage/Current(includingremote
Clampcurrent),Resistance,Capacitance,Frequency(electricaland
electronic),Diode,Continuity,andTemperature
Built‐indataloggerandtrendfeaturesstoremeasurementdatawith
convenientrecallfunctionality
Maximumreading(MAX)andMinimumReading(MIN)memoryfeatures
ReadingHOLDfeatureforfreezingdisplayedinformation(withAutoHold)
IntuitiveTFTcolorLCDdisplayandconvenientkeypadpush‐buttoncontrol
On‐screenHELPutilityforuserhintsandapplicationinformation
QuickA/DconversionsamplerateswithlowpassACfiltering
Internalreal‐timecalendarclockfortimestamping
Industrialstrengthmeterhousing
PleasevisittheExtechInstrumentswebsite(www.extech.com)for
thelatestversionsofManuals,Software,Productupdates,and
othercurrentinformation.

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3 GX900-GX930-EN V1.1 5/14
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GX930‐KEYFEATURES
MeasuresAC/DCVoltage/Current,Resistance,Capacitance,Frequency
(electricalandelectronic),DutyCycle,Diode,Insulation,Continuity,and
ThermocoupleTemperature
Newdesign,compactsize/portable
TFTcolorLCDwithclearandstablewaveformdisplay
Realtimesamplerate:500—50Msamples/second
Internalmemorystorage:3000datapoints
Triggerfunction:Risingedge,Fallingedge
Automaticsearchutility
10setsofwaveformstorage/output;waveformdatacanbe
transmittedviaBluetooth
USBPCinterface
Cursorbasedoperation
Multi‐screendisplayforchannelwaveformandFFTwaveform
SimpleMenunavigation
On‐screenHelputility
Includes1:1probewithadaptorandbatterycharger

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TABLEOFCONTENTS

INTRODUCTION.................................................................................................2
GX900‐KEYFEATURES.....................................................................................2
GX930‐KEYFEATURES.....................................................................................3
TABLEOFCONTENTS........................................................................................4
SAFETY..............................................................................................................7
INTERNATIONALSAFETYSYMBOLS..................................................................7
IEC1010OVERVOLTAGEINSTALLATIONCATEGORIES......................................7
CAUTIONS.........................................................................................................8
SAFETYINSTRUCTIONS–INPUTPROTECTIONLIMITS......................................9
FCCCOMPLIANCE...........................................................................................10
INDUSTRYCANADA(IC)COMPLIANCE...........................................................11
DIGITALMULTIMETERINSTRUCTIONS.............................................................12
DESCRIPTIONS................................................................................................12
METERDESCRIPTION......................................................................................12
INPUTTERMINALDESCRIPTION.....................................................................12
KEYPADDESCRIPTION.....................................................................................13
LCDDISPLAYDESCRIPTION.............................................................................14
QUICKSTARTGUIDE.......................................................................................15
MEASUREMENTS............................................................................................16
DCVOLTAGEMEASUREMENTS.......................................................................16
ACVOLTAGEMEASUREMENTS.......................................................................17
dBm/dBVACMEASUREMENTS.......................................................................17
LOWPASSFILTERFORACVMEASUREMENTS................................................18

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DC/ACMILLIVOLTMEASUREMENTS..............................................................18
CURRENTCLAMPMEASUREMENTS...............................................................19
DCCURRENTMEASUREMENTS......................................................................20
ACCURRENTMEASUREMENTS......................................................................21
RESISTANCEMEASUREMENTS........................................................................22
CONTINUITYCHECK........................................................................................23
DIODETEST.....................................................................................................23
TEMPERATUREMEASUREMENTS...................................................................24
CAPACITANCEMEASUREMENTS....................................................................25
FREQUENCY,DUTYCYCLE,PULSEWIDTH,andPERIODMEASUREMENTS
(ELECTRONIC).................................................................................................25
RPMMEASUREMENTS...................................................................................26
COUNTERMEASUREMENTS...........................................................................26
FUNCTIONSANDFEATURES............................................................................27
FUNCTIONMENUBASICS...............................................................................27
THE‘HELP’UTILITY.........................................................................................27
AUTOMATICANDMANUALRANGING...........................................................28
ACANDDCSIGNALS.......................................................................................28
MINIMUM(MIN)ANDMAXIMUM(MAX)READINGS....................................29
CAPTURINGPEAKVALUES..............................................................................30
RELATIVEMODE.............................................................................................30
DATAHOLDANDAUTO‐HOLDMODE............................................................31
STORINGINDIVIDUALSCREEN‐SHOTS.............................................................31
VIEWINGMEMORYDATA...............................................................................31
VIEWTRENDDATA.........................................................................................32
RECORDINGMEASUREMENTS(DATALOGGING)..............................................33

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ZOOMINGONTRENDDATA...........................................................................34
METERSETUPOPTIONS...................................................................................34
RESETTHEMETERSETUPOPTIONS................................................................34
METERINFORMATIONSCREEN......................................................................35
SETTINGTHEEVENTTHRESHOLDVALUE.......................................................35
CHANGECALIBRATIONPASSWORD.................................................................35
CALIBRATIONACCESS.....................................................................................36
BLUETOOTHTMCAPABILITY..............................................................................36
GX900SOFTWARE...........................................................................................36
SETTINGTHEDATEANDTIME.........................................................................37
AUTOMATICPOWEROFF................................................................................37
TIMEANDDATEFORMATS..............................................................................38
NUMERICFORMAT.........................................................................................38
LANGAUGEFORMAT.......................................................................................38
DIGITALOSCILLOSCOPEINSTRUCTIONS...........................................................39
MAINOSCILLOSCOPEDISPLAYDESCRIPTION.................................................39
OSCILLOSCOPEFUNCTIONTEST.....................................................................40
OSCILLOSCOPEPROBEANDCONNECTOR......................................................40
BATTERYANDFUSEREPLACEMENT.................................................................41
BATTERYREPLACEMENT................................................................................41
FUSEREPLACEMENT.......................................................................................41
SPECIFICATIONS..............................................................................................42
GENERALSPECIFICATIONS..............................................................................42
ELECTRICALSPECIFICATIONS..........................................................................43

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SAFETY
INTERNATIONALSAFETYSYMBOLS
Thissymbol,adjacenttoanothersymbolorterminal,indicatestheusermust
refertothemanualforfurtherinformation.

Thissymbol,adjacenttoaterminal,indicatesthat,undernormaluse,
hazardousvoltagesmaybepresent

Doubleinsulation

Thissymboladvisestheuserthattheterminalssomarkedmustnotbe
connectedtoacircuitpointatwhichthevoltagewithrespecttoearthground
exceeds(forthisspecificinstrument)1000VACorVDC

WARNINGThissymbolindicatesapotentiallyhazardoussituation,whichifnot
avoided,couldresultindeathorseriousinjury.
CAUTIONThissymbolindicatesapotentiallyhazardoussituation,whichifnot
avoided,couldresultindamagetotheinstrument.
IEC1010OVERVOLTAGEINSTALLATIONCATEGORIES
OVERVOLTAGECATEGORYI
EquipmentofOVERVOLTAGECATEGORYIisequipmentforconnectiontocircuitsinwhich
measuresaretakentolimitthetransientover‐voltagestoanappropriatelowlevel.Examples
includeprotectedelectroniccircuits.
OVERVOLTAGECATEGORYII
EquipmentofOVERVOLTAGECATEGORYIIisenergy‐consumingequipmenttobesuppliedfrom
thefixedinstallation.Examplesincludehousehold,office,andlaboratoryappliances.
OVERVOLTAGECATEGORYIII
EquipmentofOVERVOLTAGECATEGORYIIIisequipmentinfixedinstallations.
Note–Examplesincludeswitchesinthefixedinstallationandsomeequipmentforindustrialuse
withpermanentconnectiontothefixedinstallation.
OVERVOLTAGECATEGORYIV
EquipmentofOVERVOLTAGECATEGORYIVisforuseattheoriginoftheinstallation.Examples
includeelectricitymetersandprimaryover‐currentprotectionequipment.

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CAUTIONS
Improperuseofthismetercancausedamage,shock,injuryordeath.Readand
understandthisusermanualbeforeoperatingthemeter.
Alwaysremovethetestleadsbeforereplacingthebatteryorfuses.
Inspecttheconditionofthetestleadsandthemeteritselfforanydamagebefore
operatingthemeter.
Usegreatcarewhenmakingmeasurementsifthevoltagesaregreaterthan25VAC
rmsor35VDC.Thesevoltagesareconsideredashockhazard.
Warning!ThisisaclassAequipment.Thisequipmentcancauseinterferencein
residentialareas;inthesecasestheoperatormayberequiredtotakestepsto
avoidorminimizetheinterference.
Alwaysdischargecapacitorsandremovepowerfromthedeviceundertestbefore
performingDiode,Resistance,orContinuitytests.
Voltagechecksonelectricaloutletscanbedifficultandmisleadingbecauseofthe
uncertaintyofconnectiontotherecessedelectricalcontacts.Othermeansshould
beusedtoensurethattheterminalsarenot"live".
Iftheequipmentisusedinamannernotspecifiedbythemanufacturer,the
protectionprovidedbytheequipmentmaybeimpaired.
Thisdeviceisnotatoyandmustnotreachchildren’shands.Itcontainshazardous
objectsaswellassmallpartsthatthechildrencouldswallow.
Donotleavebatteriesandpackingmaterialunattended;theycanbedangerousin
thehandsofchildren.
Intheeventthatthedeviceisgoingtobeunusedforanextendedperiodoftime,
removethebatteries.
Expiredordamagedbatteriescancausecauterizationoncontactwiththeskin.
Always,therefore,usesuitableglovesinsuchcases.
Ensurethatthebatteriesarenotshort‐circuited.Neverincineratebatteries.

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SAFETYINSTRUCTIONS–INPUTPROTECTIONLIMITS
Thismeterhasbeendesignedforsafeuse,butmustbeoperatedwithcaution.The
ruleslistedinthissafetysectionmustbecarefullyfollowedforsafeoperation.
1. NEVERapplyvoltageorcurrenttothemeterthatexceedsthespecifiedmaximum:
InputProtectionLimits
FunctionMaximumInput
VDCorVAC1000VDC/ACrms
mAAC/DC800mA1000Vfastactingfuse
AAC/DC10A1000Vfastactingfuse(20Afor30
secondsmaxevery15minutes)
Frequency,Resistance,
Capacitance,DutyCycle,Diode
Test,Continuity
1000VDC/ACrms
Temperature1000VDC/ACrms
2. USEEXTREMECAUTIONwhenworkingwithhighvoltages.
3. DONOTmeasurevoltageifthevoltageonthe"COM"inputjackexceeds1000V
aboveearthground.
4. NEVERconnectthemeterleadsacrossavoltagesourcewhilethefunctionswitchis
inthecurrent,resistance,ordiodemode.Doingsocandamagethemeter.
5. ALWAYSdischargefiltercapacitorsinpowersuppliesanddisconnectthepower
whenmakingresistanceordiodetests.
6. ALWAYSturnoffthepoweranddisconnectthetestleadsbeforeopeningthecovers
toreplacethefuseorbatteries.
7. NEVERoperatethemeterunlessthebackcoverandthebatteryandfusecoversare
inplaceandfastenedsecurely.
8. Iftheequipmentisusedinamannernotspecifiedbythemanufacturer,the
protectionprovidedbytheequipmentmaybeimpaired.

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FCCCOMPLIANCE
Thisdevicecomplieswithpart15oftheFCCRules.Operationissubjecttothefollowingtwo
conditions:
1.Thisdevicemaynotcauseharmfulinterference.
2.Thisdevicemustacceptanyinterferencereceived,includinginterferencethatmaycause
undesiredoperation.
ThisequipmenthasbeentestedandfoundtocomplywiththelimitsforaClassBdigitaldevice,
pursuanttopart15oftheFCCRules.Theselimitsaredesignedtoprovidereasonableprotection
againstharmfulinterferenceinaresidentialinstallation.
Thisequipmentgenerates,uses,andcanradiateradiofrequencyenergyharmfulinterferenceto
radiocommunications.However,thereisnoguaranteethatinterferencewillnotoccurina
particularinstallation.Ifthisequipmentdoescauseharmfulinterferencetoradioortelevision
reception,whichcanbedeterminedbyturningtheequipmentoffandon,theuseris
encouragedtotrytocorrecttheinterferencebyoneormoreofthefollowingmeasures:
•Reorientorrelocatethereceivingantenna.
•Increasetheseparationbetweentheequipmentandreceiver.
•Connecttheequipmentintoanoutletonacircuitdifferentfromthattowhichthereceiveris
connected.
•Consultthedealeroranexperiencedradio/TVtechnicianforhelp.
FCCRadiationExposureStatement
1. Thistransmittermustnotbeco‐locatedoroperatinginconjunctionwithanyotherantenna
ortransmitter.
2. This equipment complies with FCC RF radiation exposure limits set forth for an uncontrolled
environment.
3. To maintain compliance with FCC RF exposure compliance requirements, avoid direct contact
to the transmitting antenna during transmission.
WARNING:Changesormodificationsnotexpresslyapprovedbythepartyresponsiblefor
compliancecouldvoidtheuser'sauthoritytooperatetheequipment.

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11 GX900-GX930-EN V1.1 5/14
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INDUSTRYCANADA(IC)COMPLIANCE
ThisdevicecomplieswithIndustryCanadalicense‐exemptRSSstandard(s).Operationissubject
tothefollowingtwoconditions:(1)thisdevicemaynotcauseinterference,and(2)thisdevice
mustacceptanyinterference,includinginterferencethatmaycauseundesiredoperationofthe
device.
ICRadiationExposureStatement
1. Thistransmittermustnotbeco‐locatedoroperatinginconjunctionwithanyotherantenna
ortransmitter.
2. This equipment complies with RSS 102 RF radiation exposure limits set forth for an
uncontrolled environment.
3. To maintain compliance with RSS 102 RF exposure compliance requirements, avoid direct
contact to the transmitting antenna during transmission.

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DIGITALMULTIMETERINSTRUCTIONS

DESCRIPTIONS
METERDESCRIPTION
1. LCDdisplay
2. Sub‐functionkeysF1,F2,F3,andF4
3. DataHOLDbutton
4. MAX‐MINmemorybutton
5. RotaryPrimaryFunctionSelectSwitch
6. InputjackforAmperes(A)
7. InputjackmA,uA(milli‐&micro‐Amperes)
8. Inputjack(COM)negative
9. Inputjack(positive)forallfunctions
10. DisplayBacklightcontrol
11. Informationbutton
12. NavigationarrowkeysandOKconfirmationbutton
Note:Batterycompartmentandtiltstandarelocatedontherearoftheinstrument
INPUTTERMINALDESCRIPTION
Allfunctions,exceptingcurrent,usetheVandCOMinputterminals.Separate
terminalsareprovidedforcurrentabove500mAandforcurrentbelow500mA.
Input for 0 A to 10.00 A current (20VA overload for
30 seconds on, 10 minutes off)
Input for 0 A to 500 mA current measurements
Return terminal for all measurements
Input for voltage, continuity, resistance, diode
test, conductance, capacitance

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13 GX900-GX930-EN V1.1 5/14
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KEYPADDESCRIPTION
Themeter’s12push‐buttonkeypadactivatesfeatures,augmentsfunctionsselectedby
therotaryswitch,andallowsthenavigationofthedisplayedmenustructure

F1‐F2‐F3‐F4keys
Selectssub‐functionsrelatedtothecurrentlyselectedprimary
modesetbytherotaryswitch

Cursorbuttons
Usethecursorbuttonstoselecteditemsinamenutree,adjust
displaycontrast,scrollinformation,andperformdataentry

HOLDbutton
Freezesthedisplayedreadingand,ifdesired,savesthescreenshot.TheHOLDbutton
alsoaccessestheAUTOHOLDfeaturewhichisdetailedinthisInstructionManual

MAX/MINbutton
StartsandstopstheMaximum(MAX)andMinimum(MIN)readingmemory

OKbutton
Confirmsdataentry

RotarySwitch
Selectstheprimarymeasurementfunction;foreach,themeterpresentsastandard
displayforthatfunction(range,measurementunits,andmodifiers).Seetablebelow:
V~ACvoltagemeasurements
V–DCandAC+DCvoltagemeasurements
mVDC(AC)millivolts,ac+dcmillivolt,Temperature,ClampCurrentmeasurements

Resistance,Diodetest,capacitance,continuitymeasurements
Hz%Frequencyanddutycyclemeasurements
RPMCounterRPM,Countermeasurements
AAC,dcandac+dcampsmeasurements
mAAC,dcandac+dcmilliampsmeasurements
uAAC,dcandac+dcmicroamperemeasurementsupto5,000μA
INFObutton
Openstheinformationwindow
Backlightbutton 
Selectsbacklightintensityfromlowtohigh.Alsousedtoreturnfromanauto‐power
offcondition

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LCDDISPLAYDESCRIPTION
1. Softkeylabelsindicatethefunctionofthebuttonjustbelowthedisplayedlabel.
2. BargraphAnalogdisplayfortheinputsignal(Seethe"BarGraph"sectionformore
information).
3. Primarymeasurementdisplayarea*(minussignindicatesanegativereading).
4. Rangeindicatesthemeter’spresentrangeandtherangingmode(autoormanual).
5. Batterylevelindicatesthebatterychargelevel.
6. Timeindicatesthetimesetfortheinternalclock.
7. ModeannunciatorsindicatetheMeter'smode.
8. Mini‐measurementdisplayshowstheinputvaluewhentheprimaryandsecondary
displaysarebusywithamenuscreenorpop‐upmessage.Alsoshowsthelightning
bolticon(whennecessary)inthisarea.
9. Maindisplayprovidesmeasurementinformationregardingtheinputsignal.
10. Dateindicatesthedatesetfortheinternalclock.
11. BeeperindicatestheMeter’saudiblefeedbackisenabled(thisisnotassociatedwith
thecontinuitybeeper).
12. Unitindicatestheunitsofmeasure.AuxiliaryUnitsindicatesmeasurementsthatuse
factorsinsteadofunits(suchasCrestFactor).
13. Bluetoothindicatescommunicationlinkactivity.
14. Relativeindicatesthatthedisplayedvalueisrelativetoastoredreferencevalue.
15. Secondarydisplayshowssecondarymeasurementinformationconcerningtheinput
signal.

*ThePrimarydisplayareaindicatesthemostimportantvalueoftheselectedfunction.
Thesecondarydisplaycontainsthebargraphandothervaluesthatmaybemeasuredin
additiontotheprimaryfunction(forexample,frequencymeasurementsalongwiththe
primaryACvoltagemeasurement).

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QUICKSTARTGUIDE
StepOne:Ensurethatbatteriesareinstalledandarefresh

StepTwo:CarefullyreadtheSafetysectionofthisInstructionManual

StepThree:ChecktheTableofContentstofindthesectionofthisInstruction
Manualrelatedtothedesiredtest

StepFour:Connectthetestleadstothemeterandtothedeviceundertestas
describedinthisInstructionManual’ssectionrelatedtothetestinquestion

StepFive:SafelyperformthetestasdescribedinthisInstructionManual

StepSix:ReadthemeasurementvalueontheLCDdisplay

StepSeven:Carefullydisconnectedthemeter’stestleadsfromthecircuitor
deviceundertest

StepEight:ReadthesectionofthisInstructionManualentitledFeaturesand
Functionstolearnmoreaboutthemultitudeofmeterusesandfeatures

StepNine:Disconnectthetestleadsfromthecircuitundertestandfromthe
meterandswitchOFFthemeterbeforestoring.

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MEASUREMENTS
WARNING:Riskofelectrocution.High‐voltagecircuits,bothACandDC,areverydangerousandshouldbe
measuredwithgreatcare.
1. ALWAYSturnthefunctionswitchtotheOFFpositionwhenthemeterisnotinuse.
2. IfOLappearsinthedisplayduringameasurement,thevalueexceedstheselected
range.ChangetoahigherrangeorusetheAutorangemode.
DCVOLTAGEMEASUREMENTS
CAUTION:DonotmeasureDCvoltagesifamotoronthecircuitisbeingswitchedONorOFF.Large
voltagesurgesmayoccurthatcandamagethemeter.
1. SetthefunctionswitchtotheV‐position.
2. InserttheblacktestleadbananaplugintothenegativeCOMjack.
InserttheredtestleadbananaplugintothepositiveVjack.
3. Touchtheblacktestprobetiptothenegativesideofthecircuit.
4. Touchtheredtestprobetiptothepositivesideofthecircuit.
5. Readthevoltageinthedisplay.

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ACVOLTAGEMEASUREMENTS
WARNING:RiskofElectrocution.Theprobetipsmaynotbelongenoughtocontactthelivepartsinside
some240Voutletsforappliancesbecausethecontactsarerecesseddeepintheoutlets.Asaresult,the
readingmayshow0voltswhentheoutletactuallyhasvoltageonit.Makesuretheprobetipsaretouching
themetalcontactsinsidetheoutletbeforeassumingthatnovoltageispresent.
CAUTION:DonotmeasureACvoltagesifamotoronthecircuitisbeingswitchedONorOFF.Largevoltage
surgesmayoccurthatcandamagethemeter.
1. SetthefunctionswitchtotheV~position.
2. InserttheblacktestleadbananaplugintothenegativeCOM
jack.InsertredtestleadbananaplugintothepositiveVjack.
3. Touchtheblacktestprobetiptotheneutralsideofthecircuit.
Touchtheredtestprobetiptothe“hot”sideofthecircuit.
4. Readthevoltageinthedisplay.
dBm/dBVACMEASUREMENTS
ThemeteriscapableofdisplayingACvoltageasadBvalue;relative
to1milli‐watt(dBm),relativeto1V(dBV),ortoacustomreference
value.
1. SetthefunctionswitchtotheV~position
2. PresstheF1key(MENU)ontheLCDandthen
navigatetothedBm/dBVfieldusingthearrowkeys
andthenpressOK.
3. NavigatetothemenuitemlabeleddBmandthen
pressOK.
4. Inserttheblacktestleadbananaplugintothe
negativeCOMjack.InsertredtestleadbananaplugintothepositiveVjack.
5. Touchtheblacktestprobetiptotheneutralsideofthecircuit.Touchtheredtest
probetiptothe“hot”sideofthecircuit.
6. ReadthedBmintheprimarydisplayareaandreadtheVoltageinthesecondary
displayarea.

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LOWPASSFILTERFORACVMEASUREMENTS
ThemeterisequippedwithaLowPassFilterforAC
measurements.Toactivatethefilterpleasefollowthesteps
below:
1. SettherotaryswitchtotheV~position
2. PresstheF1key(MENU)
3. MovethemenuselectortotheLOWPASSfieldandthen
pressOK
4. SelectLPF(LowPassFilter)andthenpressOK
5. PresstheF3key(RANGE)andthenpresstheF2key(MANUAL)
6. Movethemenuselectortothe500VfieldandpresstheOKkey
DC/ACMILLIVOLTMEASUREMENTS
CAUTION:DonotmeasureDC/ACvoltagesifamotoronthecircuitisbeingswitchedONorOFF.Large
voltagesurgesmayoccurthatcandamagethemeter.
1. SetthefunctionswitchtothemVposition.
2. PresstheF1key(MENU),movethemenuselectortothemenuitemlabeledmVDC
ormVAC,andthenpresstheOKkey
3. SelectmVDCormVACfromthekeyoptionsandpresstheOKkey.
4. InserttheblacktestleadbananaplugintothenegativeCOMjack.
5. InserttheredtestleadbananaplugintothepositiveVjack.
6. Touchtheblacktestprobetiptothenegativesideofthecircuit.
7. Touchtheredtestprobetiptothepositivesideofthecircuit.
8. Readthevoltageinthedisplay.

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19 GX900-GX930-EN V1.1 5/14
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CURRENTCLAMPMEASUREMENTS
1. Thismeteroffersremotecurrentclampmeasurementfunctionality.
2. SettherotaryswitchtothemVposition.
3. PresstheF1key(MENU),movethemenu
selectortotheitemlabeledCLAMPDC/AC,
andthenpresstheOKkey.
4. SelecttheitemlabeledRANGE
(0.1~100mV/A)andthenpresstheOKkey.
5. Connecttheremoteclamptotheinput
terminaljacksensuringproperpolarity.
Inserttheclamp’snegativeleadintothenegativeCOMjackandconnectthe
clamp’spositiveleadintothemeterspositiveVjack.
6. Readthemeasurementinthedisplay.

Extech Instruments
20 GX900-GX930-EN V1.1 5/14

DCCURRENTMEASUREMENTS
CAUTION:Donotmake20Acurrentmeasurementsforlongerthan30seconds.Exceeding30secondsmay
causedamagetothemeterand/orthetestleads.
1. InsertblacktestleadbananaplugintothenegativeCOMjack.
2. Forcurrentmeasurementsupto5000µADC,setthefunction
switchtotheµApositionandinserttheredtestleadbanana
plugintotheµA/mAjack.PresstheF1key(MENU)andselect
uADC,PresstheOKkey.
3. Forcurrentmeasurementsupto500mADC,setthefunction
switchtothemApositionandinserttheredtestleadbanana
plugintotheµA/mAjack.PresstheF1key(MENU)andselect
mADC,PresstheOKkey.
4. Forcurrentmeasurementsupto10ADC,setthefunction
switchtothe10Apositionandinserttheredtestleadbanana
plugintothe10Ajack.PresstheF1key(MENU)andselect
ADC,PresstheOKkey.
5. Removepowerfromthecircuitundertest,thenopenupthe
circuitatthepointwherecurrentistobemeasured.
6. Touchtheblacktestprobetiptothenegativesideofthe
circuit.
7. Touchtheredtestprobetiptothepositivesideofthecircuit.
8. Applypowertothecircuit.
9. Readthecurrentinthedisplay.