Cov qauv ntawm multimeter
Lub multimeter yog tsim los ntawm peb qhov tseem ceeb: meter taub hau, ntsuas Circuit Court thiab hloov pauv hloov. Lub multimeter yog cov cuab yeej yooj yim tshaj plaws hauv kev ntsuas hluav taws xob, thiab nws kuj yog cov cuab yeej siv dav siv. Multimeters tseem hu ua multimeters, peb lub hom phiaj ntsuas (A, V, Ω yog tam sim no, voltage, thiab tsis kam), multimeters, thiab multimeters. Multimeters muab faib ua pointer multimeters thiab digital multimeters. Kuj tseem muaj multimeter nrog oscilloscope muaj nuj nqi. Lub oscilloscope multimeter yog ib qho khoom siv ntau yam, ntau qhov ntsuas ntsuas. General multimeters tuaj yeem ntsuas DC tam sim no, DC voltage, AC voltage, tsis kam thiab suab qib, thiab lwm yam, thiab qee qhov kuj tuaj yeem ntsuas AC tam sim no, capacitance, inductance, kub thiab qee qhov tsis sib xws ntawm semiconductors (diodes, triodes). Digital multimeters tau dhau los ua qhov tseem ceeb thiab tau hloov cov ntsuas analog. Piv nrog cov cuab yeej analog, cov cuab yeej digital muaj qhov rhiab heev, siab precision, pom tseeb, muaj zog tshaj qhov muaj peev xwm, nqa tau yooj yim, thiab yooj yim dua thiab siv yooj yim.
taub hau
Lub taub hau ntawm multimeter yog rhiab heev galvanometer. Lub dial ntawm lub taub hau yog luam tawm nrog ntau yam cim, nplai cov cim thiab qhov tseem ceeb. Lub cim AV-Ω qhia tias ammeter yog multimeter uas tuaj yeem ntsuas tam sim no, voltage thiab tsis kam. Muaj ntau lub nplai kab luam tawm ntawm lub xov tooj, cov uas ib qho cim nrog "Ω" ntawm sab xis yog cov kab tsis sib haum, sab xis kawg yog xoom, sab laug kawg yog ∞, thiab qhov ntsuas tus nqi faib tsis sib npaug. Lub cim "-" lossis "DC" txhais tau hais tias ncaj qha tam sim no, "~" lossis "AC" txhais tau tias hloov pauv tam sim no, thiab "~" txhais tau tias cov kab sib faib los ntawm AC thiab DC. Ob peb kab ntawm tus lej nyob rau hauv kab kab yog qhov ntsuas qhov tseem ceeb sib raug rau cov haujlwm sib txawv ntawm tus xaiv hloov.
Kuj tseem muaj lub tshuab xoom txoj hauj lwm hloov kho pob qhov rooj ntawm lub taub hau 'meter' los kho qhov xoom txoj hauj lwm ntawm tus taw tes ntawm sab laug kawg.
hloov
Cov kev xaiv hloov ntawm lub multimeter yog ib txoj hauj lwm tig hloov. Siv los xaiv cov khoom ntsuas thiab thaj tsam. General multimeter ntsuas cov khoom suav nrog: "mA"; DC tam sim no, "V (-)": DC voltage, "V (~)": AC voltage, "Ω": tsis kam. Txhua yam khoom ntsuas tau muab faib ua ntau yam sib txawv rau kev xaiv.
Test lead thiab test lead jack
Cov thawj coj kuaj tau muab faib ua liab thiab dub. Thaum siv, ntxig cov hlau kuaj liab rau hauv lub jack cim "ntxiv", thiab ntxig cov hlau lead dub rau hauv lub jack cim "-".
Meter (hom pointer)
Nws yog lub siab rhiab heev magnetoelectric DC ammeter. Lub ntsiab kev ua tau zoo ntawm lub multimeter yeej nyob ntawm qhov kev ua tau zoo ntawm lub taub hau meter. Lub rhiab heev ntawm lub 'meter' taub hau yog hais txog DC tam sim no tus nqi ntws los ntawm lub taub hau 'meter' thaum lub pointer ntawm lub taub hau 'meter' yog deflected ntawm tag nrho cov nplai. Qhov me dua tus nqi, qhov siab dua ntawm lub taub hau meter. Qhov ntau dua qhov kev tiv thaiv sab hauv thaum ntsuas qhov voltage, nws qhov kev ua tau zoo dua. Muaj plaub kab kab ntawm lub taub hau 'meter', thiab lawv txoj haujlwm yog raws li hauv qab no: thawj kab (los ntawm sab saum toj mus rau hauv qab) yog cim nrog R lossis Ω, uas qhia txog tus nqi tsis kam. Thaum qhov hloov pauv nyob rau hauv ohm thaiv, nyeem cov kab ntsuas no. Qhov thib ob bar yog cim nrog ∽ thiab VA, qhia txog AC, DC voltage thiab DC tam sim no tus nqi. Thaum qhov hloov pauv hloov mus rau hauv AC, DC voltage lossis DC tam sim no iav, thiab qhov ntau yog nyob rau hauv txoj hauj lwm uas tsis yog AC 10V, nyeem cov nplai Hlau. Qhov thib peb kab yog cim nrog 10V, uas qhia txog AC voltage tus nqi ntawm 10V. Thaum qhov hloov pauv yog nyob rau hauv AC thiab DC voltage ntau thiab qhov ntau yog nyob ntawm AC 10V, nyeem cov kab ntawv ntsuas no. Qhov thib plaub bar, sau npe dB, qhia txog qib suab.
Meter (digital)
Lub taub hau ntawm lub tshuab hluav taws xob digital feem ntau yog tsim los ntawm A / D (analog / digital) hloov dua siab tshiab nti ntxiv rau cov khoom siv peripheral ntxiv rau cov kua siv lead ua kua. Qhov tseeb ntawm multimeter raug cuam tshuam los ntawm lub taub hau. Tus lej hloov los ntawm A/D nti feem ntau kuj hu ua Rau 3 1/2 tus lej multimeter, 4 1/2 tus lej multimeter thiab lwm yam. Cov chips feem ntau siv yog ICL7106 (3 thiab ib nrab ntawm LCD phau ntawv ntau yam classic nti, cov ntawv tom ntej yog 7106A, 7106B, 7206, 7240, thiab lwm yam), ICL7129 (4 thiab ib nrab LCD phau ntawv ntau yam classic nti), ICL7107 (3 thiab ib nrab LED phau ntawv ntau yam Classic nti).
Kev ntsuas kab
Kev ntsuas hluav taws xob yog ib lub voj voog siv los hloov ntau yam khoom ntsuas mus rau hauv me me DC tam sim no haum rau kev ntsuas ntsuas. Nws yog tsim los ntawm resistors, semiconductor Cheebtsam thiab roj teeb.
Nws tuaj yeem hloov pauv ntau yam khoom ntsuas (xws li tam sim no, voltage, tsis kam, thiab lwm yam) thiab ntau qhov sib txawv rau hauv qee qhov me me DC tam sim no los ntawm kev ua haujlwm (xws li rectification, shunting, voltage division, etc.) gauge los ntsuas .
hloov pauv hloov
Nws txoj haujlwm yog xaiv cov kab ntsuas ntau yam kom tau raws li qhov yuav tsum tau ntsuas ntawm ntau hom thiab ntau yam. Kev hloov pauv hloov feem ntau yog lub voj voj voog nrog kev ua haujlwm thiab ntau yam cim nyob ib puag ncig nws.
