Tshwj xeeb muaj nuj nqi thiab kev siv ntawm Multimeter
Multimeter muaj ntau txoj haujlwm thiab yooj yim rau siv. Nws tau dhau los ua ib qho cuab yeej tseem ceeb hauv tes ntawm cov kws tsim hluav taws xob thiab hluav taws xob. Tab sis yog tias koj xav muab kev ua si tag nrho rau nws lub luag haujlwm, koj tuaj yeem tau txais cov ntaub ntawv raug sai thiab raug. Tom qab ntawd peb yuav tsum muaj kev nkag siab tob dua ntawm qee cov yam ntxwv ntawm multimeter:
1. Puas yog digital multimeters zoo dua analog multimeters?
Kev daws: Digital multimeters tuaj yeem siv tau sai vim lawv qhov kev nyab xeeb zoo xws li qhov raug siab thiab rhiab heev, ntsuas nrawm nrawm, ntau lub zog, me me, siab input impedance, kev soj ntsuam yooj yim thiab kev sib txuas lus muaj zog. Muaj ib qho kev nyiam los hloov analog pointer watches.
Tab sis qee lub sijhawm, xws li lub sijhawm muaj kev cuam tshuam ntawm electromagnetic muaj zog heev, cov ntaub ntawv kuaj los ntawm digital multimeter yuav sib txawv heev, vim hais tias cov input impedance ntawm cov multimeter yog siab heev, thiab nws yog heev raug rau lub zog ntawm induced muaj peev xwm.
2. Thaum lub sij hawm tu, nws xav tias lub diode los yog triode nyob rau hauv Circuit Court tej zaum yuav puas los ntawm kev daws teeb meem. Txawm li cas los xij, qhov hluav taws xob conduction yog hais txog 0.6V ntsuas nrog cov ntaub ntawv diode ntawm lub ntsuas hluav taws xob, thiab cov kev taw qhia rov qab yog qhov kawg. Tsis muaj teeb meem, thiab tsis muaj qhov yuam kev thaum kuaj xyuas Circuit Court dua, vim li cas?
Kev daws: Qhov ntsuas hluav taws xob tawm los ntawm cov ntaub ntawv digital diode feem ntau yog hais txog 3-4.5V. Yog hais tias qhov kev sim transistor muaj ib tug me ntsis to los yog tus yam ntxwv nkhaus tau deteriorated, nws yuav tsis tshwm nyob rau hauv xws li ib tug tsawg voltage. Lub sijhawm no, nws yuav tsum tau siv cov ntaub ntawv analog meter × 10K tsis kam. Qhov ntsuas hluav taws xob tawm los ntawm cov ntaub ntawv no yog 10V lossis 15V. Raws li qhov ntsuas hluav taws xob no, nws yuav pom tias qhov xav tias transistor muaj qhov xau hauv qhov rov qab. Ib yam li ntawd, thaum ntsuas qhov tsis kam ntawm qee qhov ntsuas qhov ntsuas qhov ntsuas nrog qhov tsis tshua muaj hluav taws xob, siv lub ntsuas ntsuas analog tuaj yeem ua rau puas tsuaj rau cov khoom rhiab heev. Lub sijhawm no, yuav tsum siv lub ntsuas ntsuas digital los ntsuas.
3. Siv multimeter los ntsuas tus nqi attenuated voltage ntawm high-voltage sojntsuam. Nws hloov tawm tias qhov kev xeem DCV yog qhov tseeb dua, tab sis ACV yuam kev loj. Txawm tias muaj qhov tseeb multimeter, vim li cas?
Kev daws: Feem ntau ntawm cov multimeters siv qhov sib txuas sib txuas los ntsuas qhov voltage. Rau tag nrho cov kev xeem Circuit Court, lub voltmeter nws tus kheej yog sib npaug rau ib qho load uas yog input impedance. Qhov loj dua qhov load impedance, qhov me me ntawm qhov cuam tshuam rau hauv Circuit Court nyob rau hauv kev sim, thiab qhov tseeb qhov kev xeem yuav ntau dua. Tab sis tsis muaj dab tsi tuaj yeem ua tau zoo tag nrho, siab impedance yuav txi lub bandwidth ntawm kev xeem. Tam sim no, cov tswv yim impedance ntawm multimeter nrog zaus teb ntawm 100KHz ntawm kev ua lag luam yog hais txog 1.1M, yog li nws yuav muaj kev cuam tshuam zoo rau qhov voltage ntawm lub davhlau ya nyob twg 2 ntawm high-impedance load. Piv txwv li, qhov tsis kam ntawm high-voltage sojntsuam nws tus kheej yog siab heev. Nyob rau lub sijhawm no, koj yuav tsum xaiv lub multimeter uas muaj kev tiv thaiv sab hauv, xws li ESCORT (nplua nuj) 170/172/176/178/179 handheld digital multimeter muab input impedance txog 10000Ω thaum kuaj ACV, thiaj li zam qhov teeb meem no.
4. Hauv kev sim tiag tiag, kuv xav ntsuas qhov voltage thiab tam sim no, impedance ntawm lub cev muaj zog winding, thiab lwm yam, thiab kuj xav ntsuas qhov ceev. Puas muaj ib lub multimeter uas tuaj yeem paub txog qhov haujlwm no?
Kev daws: ESCORT (nplua nuj)-172 handheld digital multimeter tuaj yeem ua tau raws li koj cov kev xav tau saum toj no, thiab nws cov cai tswj kev nyab xeeb raws li International Electrotechnical Commission IEC1010-1 CATII 1000V, CATIII 600V cov qauv, yog li koj tuaj yeem siv nws nrog kev ntseeg siab thiab tsis tas yuav txhawj txog teeb meem kev nyab xeeb.
5. Puas muaj qhov pheej yig digital multimeter nrog kev ua haujlwm ruaj khov thiab ruaj khov?
Kev daws: Muaj qhov zoo hauv ntiaj teb no, thov qhia rau kuv thiab :). Tab sis kuj hais lus, cov multimeter digital uas tsim los ntawm Taiwan ESCORT (nplua nuj thiab muaj koob meej) yog tus nqi ntau dua.
6. Dab tsi yog traceability?
Solution: Traceability is a characteristic that enables measurement results or measurement standard values to be linked to specified reference standards, usually national or international measurement standards, through a continuous chain of comparisons with specified uncertainties. That is, working measuring instruments -----> measuring standard instruments ----->ntsuas cov cuab yeej siv. Piv txwv li, chav tsev ntawm huab hwm coj uas txhua tus neeg feem ntau raug rau hauv lub neej: lub kilogram, nws tus qauv yog raws li qhov hnyav ntawm 1 kilogram platinum-iridium alloy cylindrical qhov hnyav khaws cia hauv peb txheej xauv ruaj ntseg hauv tsev fuabtais hauv Sèvres, Paris. Tag nrho cov pawg loj yog raws li qhov no. Ib yam li ntawd, DCV 1V / 10V yog raws li Josephson quantum voltage array khaws cia hauv Paris International Bureau of Weights and Measures.
