Taw qhia rau Subvariation Rate thiab qhov tseeb ntawm Digital Multimeter
daws teeb meem
Kev daws teeb meem yog hais txog qhov ntsuas saib zoo npaum li cas. Paub txog qhov kev daws teeb meem ntawm ib lub 'meter' cia koj paub yog tias koj tuaj yeem pom cov kev hloov me me ntawm cov teeb liab raug ntsuas. Piv txwv li, yog tias DMM muaj kev daws teeb meem ntawm 1mV hauv 4V ntau, ces thaum ntsuas lub teeb liab ntawm 1V, koj tuaj yeem pom qhov hloov me me ntawm 1mV (1/1000th ntawm ib volt)
Yog tias koj ntsuas tsawg dua 1/4 nti (lossis 1 hli), koj yuav tsis siv tus pas ntsuas ntiv tes (lossis centimeters). Yog tias nws yog 98.6 degree F, nws tsis muaj txiaj ntsig los ntsuas nws nrog tus pas ntsuas kub uas tsuas muaj cov lej lej. Koj yuav xav tau tus pas ntsuas kub nrog qhov kev daws teeb meem ntawm 0.1 degree F.
Tus lej thiab cov lus yog siv los piav txog qhov kev daws teeb meem ntawm lub rooj. DMMs raug cais los ntawm cov lej thiab cov lus uas lawv tuaj yeem tso tawm.
Ib lub rooj 3½-tus lej uas tuaj yeem pom peb tus lej tag nrho ntawm 0 mus rau 9, thiab tus lej ib nrab (tsuas yog 1 lossis tsis muaj). A 3. A 4.
Kev siv cov lus los piav txog qhov kev daws teeb meem ntawm cov rooj digital yog qhov zoo dua li siv cov khoom los piav qhia, thiab qhov kev daws teeb meem ntawm 3 thiab ib nrab ntawm cov ntxhuav tau nce mus rau 3200 lossis 4000 lo lus.
3200 suav cov ntsuas ntsuas digital muab kev daws teeb meem zoo dua rau qee qhov kev ntsuas. Piv txwv li, ib tug 1999- lo lus 'meter', thaum ntsuas qhov voltage ntau dua 200V, koj tsis tuaj yeem tso tawm 0.1V. Txawm li cas los xij, 3200- lo lus digital meter tseem tuaj yeem tso tawm 0.1V thaum ntsuas qhov voltage ntawm 320 volts. Thaum ntsuas qhov ntsuas hluav taws xob siab dua 320V thiab qhov kev daws teeb meem ntawm 0.1V yuav tsum ua tiav, yuav tsum tau them nyiaj ntau dua 20,000- lo lus digital meter.
Kev Taw Qhia Qhov tseeb
Qhov tseeb yog hais txog qhov ua yuam kev siab tshaj plaws hauv ib puag ncig siv tshwj xeeb. Hauv lwm lo lus, precision yog siv los qhia
Qhov ze ntawm qhov ntsuas tus nqi ntawm digital multimeter mus rau qhov tseeb tus nqi ntawm lub teeb liab nyob rau hauv kev sim.
Rau DMMs, qhov tseeb feem ntau yog qhia hauv feem pua ntawm kev nyeem ntawv. Piv txwv li, lub ntsiab lus ntawm 1 feem pua ntawm kev nyeem ntawv qhov tseeb yog: thaum cov zaub ntawm digital multimeter yog 100.0V, qhov tseeb voltage yuav nyob nruab nrab ntawm 99.0V thiab 101.0V .
Cov txiaj ntsig tshwj xeeb yuav raug ntxiv rau qhov yooj yim precision hauv cov ntawv qhia tshwj xeeb. Nws lub ntsiab lus yog tus naj npawb ntawm cov lus yuav tsum tau ntxiv los hloov qhov kawg ntawm cov zaub. Hauv qhov piv txwv yav dhau los, qhov tseeb yuav raug suav tias yog ± (1 feem pua ntxiv rau 2). Yog li, yog GMM nyeem 100.0V, qhov tseeb voltage yuav nyob nruab nrab ntawm 98.8V thiab 101.2V.
Qhov tseeb ntawm lub ntsuas ntsuas analog yog xam raws li qhov ua yuam kev tag nrho, tsis yog cov ntawv nyeem. Qhov tseeb raug rau cov ntsuas ntsuas analog yog ± 2 feem pua lossis ± 3 feem pua ntawm tag nrho cov nplai. Qhov tseeb qhov tseeb ntawm DMM yog nyob nruab nrab ntawm ± (0.7 feem pua ntxiv rau 1) thiab ± (0.1 feem pua ntxiv rau 1) kev nyeem ntawv, lossis ntau dua.
