Troubleshooting Common Issues of Digital Multimeters
(1) Tsis muaj zaub ntawm lub ntsuas
Ua ntej, xyuas seb lub roj teeb voltage yog li cas (ib lub roj teeb 9V feem ntau yog siv; txawm tias ib qho tshiab yuav tsum tau sim). Tom ntej no, xyuas seb lub fuse puas tau tawg, yog tias qhov ntsuas hluav taws xob ua haujlwm tau zoo, thiab yog tias tam sim no-txheej resistor qhib-circuited. Tom qab ntawd, tshawb xyuas lub rooj tsav xwm hauv Circuit Court rau corrosion, luv Circuit Court, los yog qhib circuits (tshwj xeeb tshaj yog nyob rau hauv lub main power supply circuit). Yog tias muaj teeb meem zoo li no, ntxuav lub rooj tsav xwm hauv Circuit Court, thiab tam sim ntawd qhuav thiab rov kho cov chaw cuam tshuam.
Yog tias lub rooj tsav xwm hauv Circuit Court yog qhov qub, ntsuas qhov voltage ntawm ob lub hwj chim input pins ntawm cov khoom sib xyaw ua ke (IC). Yog tias qhov hluav taws xob zoo li qub, IC puas lawm thiab yuav tsum tau hloov. Yog hais tias qhov voltage yog txawv txav, kos rau lwm cov ntsiab lus luv luv. Yog pom tau, hais rau lawv tam sim ntawd. Yog tias tsis pom cov ntsiab lus luv luv lossis qhov teeb meem tshwm sim tom qab kho, IC muaj qhov luv luv hauv Circuit Court thiab yuav tsum tau hloov.
(2) Kev ua haujlwm tsis muaj zog
Visually soj ntsuam lub Circuit Court board rau burnt resistors nyob rau hauv lub resistance range Circuit Court. Yog tias pom muaj, hloov lawv tam sim ntawd. Yog tias tsis yog, sim txhua qhov txuas txuas thiab hloov qhov tsis raug. Yog hais tias tag nrho cov khoom siv peripheral zoo li qub, qhov sib xyaw ua ke yuav raug puas tsuaj thiab yuav tsum tau hloov.
(3) Kev nyeem tsis raug ntawm qhov voltage thaum ntsuas qhov hluav taws xob siab, lossis nyeem tsis raug / tsis ruaj khov tom qab ntsuas ntev
Cov kev ua yuam kev no feem ntau yog tshwm sim los ntawm kev ntsuas tsis txaus ntawm ib lossis ntau yam khoom. Yog tias cov khoom no tau pom tias kub hauv ob peb feeb tom qab tso tseg qhov ntsuas, nws yog vim qhov thermal nyhuv tshwm sim los ntawm kev ntsuas lub zog tsis txaus. Cov tivthaiv (los yog kev sib xyaw ua ke) yuav tsum tau hloov.
(4) Kev siv tsis tau tam sim no
Hom kev ua txhaum no feem ntau tshwm sim los ntawm kev ua haujlwm tsis raug. Xyuas seb qhov tam sim no-limiting thiab voltage-dividing resistors raug hlawv; yog tias muaj, hloov lawv. Tom qab ntawd, xyuas seb cov xov hlau txuas mus rau lub amplifier puas puas lawm; yog tias muaj, rov txuas lawv. Yog tias qhov teeb meem tseem tshuav, hloov lub amplifier.
(5) Kev nyeem tsis ruaj khov nrog cov lej dhia
Xyuas seb tag nrho lub rooj tsav xwm hauv Circuit Court puas ntub los yog muaj cov dej ntws tawm; yog tias muaj, ntxuav lub rooj tsavxwm thiab kom qhuav nws. Tshawb xyuas qhov kev sib cuag tsis zoo los yog cov pob qij txha txias hauv cov khoom siv hluav taws xob (xws li cov khoom kuaj xyuas); Yog tias pom, rov ua dua lawv. Tshawb xyuas cov resistors uas tau hloov pauv ntawm tus nqi lossis cov khoom uas ua rau kub kub tam sim ntawd tom qab kev sim (ib qho cim ntawm kev ntsuas hluav taws xob tsawg); yog tias muaj teeb meem zoo li no, hloov cov khoom siv.
(6) Kev nyeem tsis raug
Qhov tshwm sim no feem ntau yog tshwm sim los ntawm kev ua tsis tau zoo los yog cov capacitors hauv kev ntsuas Circuit Court; lub faulty Cheebtsam yuav tsum tau hloov. Tshawb xyuas qhov tseem ceeb ntawm cov resistors hauv Circuit Court (nrog rau cov cuam tshuam los ntawm thermal drift); Yog hais tias qhov kev tiv thaiv tau hloov los yog drifts nrog kub, hloov lub resistor. Xyuas seb cov resistors thiab capacitors nyob rau hauv qhov siv voltage voj ntawm A / D converter puas lawm; yog tias muaj, hloov lawv.
