Mastech MY67 User manual

CONTENTS
1. SAFETY INFORMATION .1
2. DESCRIPTION .. 3
3. OPERATINGINSTRUCTION ..6
3.1MEASURINGVOLTAGE .6
3.2MEASURINGCURRENT 6
3.3MEASURINGRESISTANCE ..7
3.4MEASURINGFREQUENCY 7
3.5MEASURINGCAPACITANCE 8
3.6CONTINUITY TEST .. ...8
3.7DOIDE TEST ..8
3.9TRANSISTORTEST .9
4. SPECIFICATIONS .9
5. ACCESSORIES 13
6. BATTERY & FUSE REPLACEMENT 14

1. SAFETYINFORMATION
Thismultimeterhasbeen designed according to
IEC-1010 concerning electronicmeasuringinstruments
withanovervoltagecategory(CAT )and pollution 2.
Followall safetyand operatinginstructionstoensure
thatthemeterisused safelyand iskeptingood
operating condition.
1.1PRELIMINARY
※Whenusingthismeter,theusermustobserveall
normalsafetyrulesconcerning:
—Protection against thedangersofelectricalcurrent.
—Protection ofthemeteragainst misuse.
※Full compliancewithsafetystandardscanbe
guaranteed onlyifused withtestleadssupplied.If
necessary,theymustbereplaced withthesamemodelor
sameelectronicratings.Measuring leadsmustbein
good condition.
1.2DURINGUSE
※Neverexceed theprotectionlimitvaluesindicatedin
specificationsforeachrangeofmeasurement.
※Whenthemeterislinked tomeasurementcircuit, do
not touchunused terminals.
※Whenthevaluescaletobemeasured isunknown
beforehand,settherangeselectoratthehighest
position.
※Beforerotatingtherangeselectortochange
functions,disconnecttestleadsfromthecircuitunder
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test.
※Whencarryingoutmeasurementson TVor
switching powercircuits,alwaysrememberthatthere
maybehighamplitudevoltagespulsesattestpoints
whichcandamagethemeter.
※Neverperformresistancemeasurementsonlive
circuits.
※Alwaysbecarefulwhenworkingwithvoltages
above60Vdcor30Vacrms.Keepfingersbehind the
probebarrierswhilemeasuring.
1.3SYMBOLS
Importantsafetyinformation,refertotheoperating
manual.
Dangerousvoltagemaybepresent.
Earthground
Doubleinsulation (Protectionclass )
1.4MAINTENANCE
Beforeopening themeter,alwaysdisconnecttest
leadsfromall sourcesofelectriccurrent.
Forcontinueprotectionagainstfire,replacefuse
onlywiththespecifiedvoltageand currentratings:F1:
2A/250VF2: 10A/250V
Ifanyfaultsorabnormalitiesareobserved,the
metercannotbeused anymoreandithastobe
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checkedout.
Neverusethemeterunlesstheback coverisin
placeandfastened fully.
Toclean themeter,useadampclothand mild
detergentonly, donot useabrasivesorsolventson it.
2. DESCRIPTION
Thismeterisanautorangingprofessionalinstrument
with33/4digitLCD display,capableofperforming
functions:
-DC voltagemeasurement
-ACvoltagemeasurement
-DC current measurement
-ACcurrent measurement
-Resistancemeasurement
-Capacitancemeasurement
-Frequencymeasurement
-Diodetest
-Transistortest
-Audiblecontinuitytest
Names ofcomponents
1-4. buttons
5. Rotaryswitch
6. A input jack
7. mAinput jack
8. V/Ω/Hzinput jack
9. COMinput jack
10. Transistorinput jack
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2.1SELECT(Functionselectionbutton)
Thisbuttonisused toselectACAorDCAmeasuring
mode.
2.2RANGE (Auto/manualrangeselectionbutton)
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Thiskeyistheauto/manualkey.Poweron defaultis
automeasurement, andpress onetimetoswitchtothe
manualmeasurement. Inmanualmeasurementmode,
the systemwill jumpup onemodeforeachpress until
thehighestmode,thenreturntothelowestmodeasa
loop.Ifpressthekeyover2seconds,thesystemwill
switchbacktoautomeasurementstatus.Frequency
and capacitancemeasurementcannotusemanual
measurement. Foxexample,atvoltagerangethe
changesareasthefigure.
2.3REL(Relativevaluemeasurement)
Thebutton isforrelativevaluemeasurementexceptHz,
diodeand continuity.
Pushthebuttontogetrelativemeasurementmode,
“REL”annunciatedisplayonLCD.Butstorethe
displayed reading asareferencevalue. IntheRelative
mode,thevalueshownon theLCDisalways the
differencebetweenthestored referencevalueandthe
presentreading.Ifthenewreading isthesameasthe
referencevalue, thedisplaywill bezero.
2.4DATAHOLD
Whenthisbuttonispushed,thedisplaywill keep the
lastreading and “ ” symbolwill appearon theLCD.
Pushing it againreturnsthemetertonormalmode.
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2.5INPUTJACKS
Theunithasfourinputjacksthatareprotectagainst
overload tothelimits.During use,connecttheblacktest
lead totheCOMjackandthered testlead asshown
below:
Function
Redlead
connection
Input limits
V V/Ω/Hz 1000V dcor750V rmsac
ΩV/Ω/Hz 250V dcorrmsac
V/Ω/Hz 250V dcorrmsac
V/Ω/Hz 250V dcorrmsac
μA/mA mA 500mA dcorrmsac
A A 10A dcorrmsac
μA/mA and A rangesareprotected byfuses.
3.OPERATING INSTRUCTION
3.1MEASURINGVOLTAGE
1. Connect theblacktest lead totheCOMjackandthe
redtest lead totheV/Ωjack.
2.Settherotaryswitchatthedesired V orV ~
rangepositionand connecttestleadsacrossthe
sourceorload undermeasurement.
3.Read LCD display.Thepolarityof thered connection
will beindicated whenmaking adcvoltage
measurement.
3.2MEASURINGCURRENT
1.ConnecttheblacktestleadtotheCOMjackandthe
read test lead tothemA jackforamaximumof500mA.
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Foramaximumof10A, movethered lead totheA jack.
2.Setthefunctionswitchat μA, mAorArangetobe
used and push “SELECT”button toselectDCAorACA
measuring mode.
3.Connecttestleadsinserieswiththeload under
measurement.
4.Read LCDdisplay.Thepolarityofthered lead
connectionwill beindicatedwhenmaking aDC
measurement.
3.3MEASURINGRESISTANCE
1. Connect theblacktest lead totheCOMjackandthe
redtest lead totheV/Ω/Hzjack. (NOTE: Thepolarityof
redlead connection ispositive “＋”)
2.Settherotaryswitchat Ωpositionand connecttest
leadsacrosstheresistanceundermeasurement. Read
LCDdisplay.
NOTE:
1.Forresistanceabove1MΩ,themetermaytakeafew
secondstostabilizereading.
2. Whentheinputisnotconnected,i.e.atopen circuit,
thefigure “OL”will bedisplayed fortheoverrange
condition.
3.Whencheckingin-circuitresistance,besurethe
circuitundertesthasall powerremoved and all
capacitorsarefull discharged.
3.4MEASURINGFREQUENCY
1. Connect theblacktest leadstotheCOMjackand the
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redtest lead totheV /Ω/Hzjack.
2.SettherotaryswitchatHzposition andconnecttest
leadsacross thesourceorload undermeasurement.
3.5 MEASURINGCAPACITANCE
1. Set therotaryswitchat desired position.
2.Beforeinserting capacitorundermeasurementinto
capacitancetesting socket, besurethatthecapacitor
hasbeen discharged fully.
3.Whenmeasuring capacitorswithshorterleads,a
testing adapterisprovided withthemeter.Insertthe
adapterintothecapacitancetestingsocketonthefront
paneltocontinuemeasurements.
WARNING!
Toavoidshock,besurethecapacitormeasuring
adapterhasbeen removed beforechanging toanother
functionmeasurement.
3.6CONTINUITYTEST
1. Connect theblacktest lead totheCOMjackandthe
redtestlead totheV/Ω/Hzjack(Note:thepolarityof
redlead connection ispositive “+”).
2.Settherotaryswitchat position andconnecttest
leadsacross twopointsofthecircuitundertesting.If
continuityexists(i.e.resistanceless thanabout50Ω),
built inbuzzerwill sound.
3.7DIODE TEST
1. Connect theblacktest lead totheCOMjackandthe
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redtestleadtotheV/Ω/Hzjack.(NOTE: Thepolarityof
redlead connection ispositive“+”)
2.Settherotaryswitchat positionand connectthe
redlead totheanode, theblacklead tothecathodeof
thediodeundertesting.Themeterwill showtheapprox.
Forwardvoltagedrop ofthediode.
3.8TRANSISTORTEST
1. Set therotaryswitchat hFE position.
2.IdentifywhetherthetransistorisNPNorPNPtype
and locateEmitter,BaseandCollectorlead.Insert
leadsofthetransistortobetested intoproperholesof
thetesting socketon thefront panel.
3.LCD displaywill showtheapproximatehFEvalueat
thetest conditionofbasecurrent 10µAand Vce3.2V.
4. SPECIFICATIONS
Accuracyisspecified foraperiod ofoneyearafter
calibrationandat18°Cto28°C(64°Fto82°F)with
relativehumidityto80%.
Accuracyspecificationsaregiven as:
±% ofreading ±numberofleast significant digits.
4.1GENERAL
MAXIMUMVOLTAGEBETWEENTERMINALSAND
EARTHGROUND: 1000V DCor700 rmsAC(sine)
FUSE PROTECTION: µA, mA: F500mA/250V
A: F10A/250V
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