Multimeter kho tswv yim rau faulty meter yuav tsum xub xyuas cov
Yog tias txhua lub zog tsis tuaj yeem ua haujlwm, yuav tsum tsom mus rau kev kuaj xyuas lub zog hluav taws xob thiab A / D converter circuit. Txheeb xyuas qhov chaw fais fab, koj tuaj yeem tshem tawm cov roj teeb laminated, nias lub hwj huam hloov, nrog tus cwj mem zoo txuas nrog lub rooj ntsuas hluav taws xob tsis zoo, tus cwj mem tsis zoo txuas nrog lub hwj chim zoo (rau digital multimeter), qhov hloov mus rau cov ntaub ntawv ntsuas ob lub raj, yog tias cov khoom siv yog lub raj thib ob qhov zoo voltage, ces lub hwj huam mov ib feem ntawm qhov zoo, yog tias qhov sib txawv loj, nws txhais tau hais tias lub hwj huam mov ib feem ntawm qhov teeb meem. Yog tias muaj qhov qhib Circuit Court, tsom mus rau kev kuaj xyuas lub hwj chim hloov thiab cov roj teeb coj, thiab lwm yam.. Yog tias muaj kev cuam tshuam luv luv, nws yuav tsum tau siv txoj kev sib txuas kom maj mam txiav cov khoom siv hluav taws xob, tsom mus rau kev kuaj xyuas. ua haujlwm amplifiers, timers thiab A/D converters. Yog hais tias ib tug luv luv Circuit Court tshwm sim, nws feem ntau puas ntau tshaj ib tug integrated tivthaiv. Tshawb xyuas A / D converter tuaj yeem ua tiav tib lub sijhawm nrog lub ntsuas ntsuas, sib npaug rau DC lub taub hau ntawm analogue multimeter.
Kev tshuaj xyuas tshwj xeeb:
(1) qhov ntau ntawm cov lus ntsuas mus rau qhov qis tshaj DC voltage iav.
(2) Ntsuas seb qhov A / D converter kev khiav hauj lwm voltage yog li cas. Raws li tus qauv ntawm A / D converter siv nyob rau hauv lub rooj, sib xws rau V + tus pin thiab COM tus pin, qhov ntsuas tus nqi piv nrog nws cov nqi raug zoo ib yam.
(3) Ntsuas qhov siv hluav taws xob ntawm A / D converter, qhov siv hluav taws xob ntawm cov khoom siv digital feem ntau yog 100mV lossis 1V, piv txwv li, ntsuas DC voltage ntawm VREF + thiab COM, yog tias nws txawv ntawm 100mV lossis 1V, nws tuaj yeem yuav tau kho los ntawm sab nraud potentiometer.
(4) Txheeb xyuas tus naj npawb ntawm cov lus qhia qhov twg cov tswv yim yog xoom, luv luv qhov zoo davhlau ya nyob twg IN + thiab qhov tsis zoo davhlau ya nyob twg IN- ntawm A / D converter kom cov input voltage Vin=0 thiab cov cuab yeej qhia "{{4 }} 0 or "00 00.
(5) Txheeb xyuas cov zaub kom pom qhov ci ntsa iab. Luv luv lub xeem davhlau ya nyob twg TEST tus pin mus rau qhov zoo fais fab mov davhlau ya nyob twg V + kom lub logic hauv av ua siab muaj peev xwm thiab tag nrho cov digital circuits tsis ua hauj lwm. Vim hais tias ntawm DC voltage ntxiv rau txhua tus mob stroke, tag nrho cov strokes yog ci thiab lub txee zaub qhia "1888, lub txee zaub qhia" 18888. Yog tias tsis muaj kev cuam tshuam tsis zoo, xyuas qhov sib txuas cov zis tus pin ntawm A / D converter thiab cov roj hmab conductive (los yog xaim), thiab cov zaub ntawm kev sib cuag tsis zoo thiab kev cuam tshuam ntawm qhov xwm txheej.
