Multimeters for Electronics Work

Saka iwe unoda multimeter. Zvichida mukuru wako akafa, pamwe uri kungopinda mukugadzirisa zvemagetsi, kana kuti pamwe wakaneta nekukwereta Fluke yewaunoshanda naye pese paunoda kutarisa voltage. Chero chikonzero, kutora mita chaiyo hakuna kutwasuka sekuti YouTube inoita kuti itaridzike.

Ndanga ndichigadzirisa zvemagetsi kweanoda kusvika makore masere ikozvino, kunyanya zvinhu zvevatengi uye zvimwe zvigadzirwa zvemaindasitiri, uye ndakapfuura nemamita matanhatu kana manomwe akasiyana. Mamwe aive marara, mamwe aive akanaka, uye imwe yaive hombe kusvika ndaidonhedza kubva pamanera (mhosva yangu, kwete yemamita).

Vazhinji vanotanga vanofunga kuti vanofanirwa kushandisa $400 paFluke 87V ipapo. Icho hachisi chokwadi kune vanhu vazhinji. Musandinzwire zvisizvo-Fluke inoita mamita akanakisa, uye kana uri kuita basa rehunyanzvi reHVAC kana kugadzirisa muindasitiri uko kuverenga kusiriko kunogona kuita zviuru nezviuru munguva yekusashanda, hongu, wana Fluke. Asi kune zvemagetsi hobbyists kana basa rakareruka nyanzvi? Pane nzvimbo huru yepakati.

Parizvino ndiri kushandisa Brymen BM869s semita yangu huru. Mari inosvika $180-200 zvichienderana nekwaunoitenga. Iine zviuru makumi matanhatu zvekuverenga resolution izvo zvinoita kunge zvekushambadzira zvisina musoro asi zvinotoita mutsauko paunenge uchiedza kuona shanduko diki mumagetsi kana ikozvino. Kuverenga kunovandudzwa nekukurumidza-kanenge ka50 pasekondi zvinoenderana nezvavanoda-zvinove zvakakosha kupfuura zvandaifunga kuti zvaizoita ndisati ndava nemamita ine sampling inokurumidza. Paunenge uchiongorora uchitenderedza dare redunhu uchiedza kutsvaga dambudziko, iyo mhinduro yekukurumidza inokubatsira kuona nyaya nekukurumidza.

Pamberi peBrymen, ndaiva neUNI-T UT61E kwemakore matatu. Yakabhadharwa pamwe madhora makumi matanhatu neshanu paAmazon kumashure muna 2019 (mitengo yakakwira kubva ipapo, zvakanyanya semadhora makumi masere nemakumi mapfumbamwe izvozvi). Meta iyoyo yainyatsokwana 90% yezvandakaita. Chikonzero chega chandakakwidziridza ndechekuti ndakatanga kuita basa rakawanda rekuongorora mota uye ndaida kukurumidza sampling rate uye zvirinani AC kuyerwa.

multimeter

Wese munhu anotaura nezve "kurongeka" asi vanhu vazhinji havatomboziva kuti kurongeka kunorevei. Kana mita ichiti "±0.5% + 3 manhamba" haisiriyo nhamba imwe chete-idzo mbiri dzakasiyana dzakabatanidzwa. Chikamu chezana chinobva pahuwandu hwekuverenga, uye chikamu chemanjiti chigadziriswe. Saka kana iwe uchiyera 10.00V neiyo spec, yako chaiyo voltage inogona kuve chero kubva 9.92V kusvika 10.08V. Kune akawanda emagetsi kugadzirisa matambudziko, izvi hazvina basa zvachose. Uri kutsvaga njanji dze5V dzakadonha kusvika ku4.3V nekuda kweiyo capacitor yakaipa, kwete kuyedza kuenzanisa zviridzwa.

Pane kurongeka kwakakosha: kana iwe uchiita chaiyo analogi basa, sensor calibration, kana kuyedza magetsi ekuti ripple specs. Ipapo hongu, iwe unoda chimwe chinhu chiri nani kupfuura ± 0.5% basic DC kunyatsoita. My Brymen is ± 0.03% iyo inowandisa pane zvandinoda, asi yakauya nepasuru.

Kuyera kwazvino ndiko uko mita dzakachipa dzinonyatso ratidza zvadzisingakwanisi. The burden voltage-ndiko kudonha kwevoltige pa mita ye internal shunt resistor-inogona kukwirisa zvakakwana pamamita akachipa zvekuti zvinotokanganisa seketi yauri kuyera. Ndakayedza yangu yekare $20 metres (handigone kana kurangarira mhando) uye yaive neinenge 0.8V mutoro voltage pa10A renji. Izvo zvakaipa. Iyo UNI{9}T yaisvika 0.3V. Iyo Brymen iri pasi pe0.1V. Paunenge uchiyera ikozvino mune 5V dunhu, iwo musiyano unokosha.

Maonero asingafarirwe pamwe, asi ini ndinonyatsoda bhuku rekutanga kune akawanda emabasa. Autoranging metres yakanakira kana usingazive kuti voltage yauri kutarisa ndeipi, asi pandinenge ndichishanda pabhodhi pandinoziva njanji dzese (3.3V, 5V, 12V, chero chii), ndinongoseta kamwe chete uye ndosiya ipapo. Kuchinjanisa pakati pe auto ne manual kunofanira kuve nyore asi-mamwe mamita achiita kuti utarise mamenu zvinosvota.

Fluke 115 (inenge $200-220) ingangove ndiyo inonyanya kufarirwa yemamita "prosumer" kunze uko uye nechikonzero chakanaka. Izvo hazvigone kuparara, zvine hukuru hwekuvaka mhando, uye iyo interface yese inongo ... inonzwisisika. Zvese zviri pauri kutarisira kuti zvive. Ndakakwereta imwe kwemwedzi mishoma uye nekutendeka chikonzero chega chandisina kutenga yaive yekuti ndaida mamwe maficha aive naBrymen. Kana iwe uchingoda voltage, yazvino, kuramba, kuenderera, uye diode bvunzo, iyo 115 inoita zvese izvo zvakanaka. Rutsigiro rwavo rwewaranti rwakanakawo zviri pamutemo-ndanzwa nyaya dzakawanda kubva kuvagadziri vemagetsi vaive neFluke kutsiva mamita akatadza mushure memakore ekushungurudzwa.

Apa ndipo pandinenge ndichiita kunge ndiri kuparidza asi chero. Muyero weCAT pamamita ako hausi kushambadzira chete. CAT II yakanakira zvemagetsi uye yakaderera voltage basa. CAT III ndeyekugovera mapaneru uye kuiswa kwakagadziriswa. CAT IV ndeye utility level zvinhu. Iyo voltage rating (se600V kana 1000V) inosanganiswa neCAT rating kuti ikuudze izvo mita inogona kubata zvakachengeteka maererano nezvinopfupika uye kukanganisa mamiriro.

Mamita mazhinji akachipa ane manyepo kana anotsausa ekuchengetedza zviyero. Pakave nekukakavadzana pamusoro peizvi makore mashoma apfuura-EEVblog yakadzura maAmazon metres akachipa ayo aiti CAT III 1000V asi iine mvumo yaisatombokodzera CAT II. Vhidhiyo chaiyo yaive yemamita kubva kukambani inonzi "AstroAI" ndinofunga, uye Dave Jones akayera kubvumidzwa kwePCB kunge 2mm pavaida kuve 8mm kana chimwe chinhu chechiyero chavanoti. (Kwakabva: eevblog.com).

Kana iwe uchingoshanda neakadzika voltage DC zvinhu (pasi pe48V), izvi hazvina basa. Asi kana iwe uchiita chero mains voltage basa, tenga mita kubva kune inozivikanwa brand ine zvitupa zvekuchengetedza zviri pamutemo. Izvi zvinoreva Fluke, Brymen, Keysight, Klein, Amprobe, kana zvakafanana. Kwete zvisina kujairika mabhureki eAmazon ane 5-nyeredzi wongororo ayo asingafungire zvachose.

Continuity beeper ingangove yakanyanya-inoshandiswa pane chero multimeter kana uchiita basa rekugadzirisa. Kuongorora zvikabudura, kutarisa kubatana, kutsvaga maPCB -unoishandisa nguva dzose. Mamwe mamita ane kunonoka kusati kwatanga beep izvo zvinoita kuti chimiro chishaye basa. Kunonoka kunofanira kunge kuri pasi pe50ms. Chero chinhu chakareba uye uri kufambisa maprobes uchinetseka kuti pane kuenderera mberi here kana kuti mita haisati yarira.

Meta yangu yekare isina{0}zita ine pamwe 200-300ms kunonoka. Absolute marara ekukurumidza kuenderera mberi kwekutarisa. UNI{8}T yanga irinani, pamwe ingangoita 30-40ms. Iyo Brymen ndeye pakarepo. Zvakafanana neFlukes ini ndashandisa-kuenderera kwavo mhinduro yakanaka.

Mamwe mamita anorirawo pakakwirira pachikumbaridzo. Kuenderera mberi hakuna kufanana nekushomeka kwakaderera-zvaunoda kuti bhipi riite se20-50Ω kana zvishoma. Ndakashandisa mamita anorira kusvika ku200Ω ayo anokunda chinangwa paunenge uchiedza kusiyanisa pakati pekubatana kwakanaka uye kumucheto.

multimeter

Wese munhu anotarisa pane kuyerwa specs uye anofuratira chokwadi chekuti iwe unofanirwa kunyatso kushandisa chinhu. Screen quality inokosha. Backlight inokosha. Mabhatani marongerwo akakosha. Kunyangwe zvinotungamira zvinogara mumajeki zvine basa (ndiri kutarisa kwauri, Mastech MS8268-idzo jacks dzaityisa).

The Brymen ine chiratidziro chakanaka chaizvo-madijiti machena pane rima rekumashure, riri nyore kuverenga mune chero mwenje. Iyo backlight inopenya zvakakwana kuti ushandise mune dim mamiriro asi isina kupenya zvakanyanya zvekuti inoparadza chako chiratidzo chehusiku kana uri kushanda munzvimbo ine rima. Diki diki, asi inoongwa.

Kuchengetedzwa kwekutungamira ndechimwe chinhu hapana anotaura nezvazvo. Unoisa kupi zvinotungamira kana wapedza? Mamwe mamita ane zvibatiso zvakavakwa mukati, mamwe haana. Ini ndinoshandisa magineti anotungamira anonamira kubhokisi rangu rekushandisa iro rinoshanda zvakanaka, asi chimwe chinhu chimwe chekufunga nezvazvo.

Ah uye hechino chimwe chinhu chinondisvota: mamita asina fuse yakaparadzana yemA siyana uye 10A renji. Kana ukaridza fuse huru, unorasa ese ari maviri. Mamita arinani ane mafuse maviri akaparadzana saka unogona kuramba uchiyera makwiriri epamusoro kana fuse yemA ikavhuvhuta. Iyo Brymen ine izvi, akawanda akachipa metres haaite.

Mamita mazhinji anoshambadza kuyerwa kwekushisa sechinhu. NeBrymen unowana K-mhando thermocouple inosanganisirwa. Ndakashandisa zvichida ... kashanu? Mumakore matatu? Hazvirevi kuti haishande, ingori kuti kune mazhinji emabasa ekuyera tembiricha, infrared thermometer kana yakatsaurirwa thermocouple mita iri nani. Kurongeka kweiyo multimeter tembiricha basa rinowanzoita senge ± 1-2 dhigirii iyo yakanaka kune yakakasharara cheki asi haina kunaka kana iwe uchinyatsoda data rekushisa.

Pazvinobatsira: kutarisa tembiricha yechikamu pabhodhi kana uchifungidzira kuti chimwe chinhu chiri kupisa. Iwe unogona kuongorora chip kana regulator uye kuwana kuverenga. Asi kune ambient tembiricha kana chero chimwe chinhu, ini ndaizoshandisa chakasiyana chishandiso.

Dzakanakira zvinhu zvakakosha. Ini ndinochengeta imwe mumotokari yangu yekushandisa yekutarisa bhatiri voltage uye kwete zvimwe zvakawanda. Kurongeka kwacho kunopokana, mhando yekuvaka inopokana, uye chengetedzo ine mubvunzo. Asi pazviyero zviri nyore zveDC voltage munzvimbo dzakaderera-zvine njodzi, zvinoshanda. Ingo usavavimbe navo pane chero chinhu chakakosha uye zvechokwadi usavashandise pane mains voltage.

Ndakaedza zvisingaite $18 metres kubva kuHarbour Freight kamwe (iyo modhi yaive yakafanana ne37772, vangangove vakaichinja parizvino) uye ndikaenzanisa kuverenga neBrymen yangu. PaDC voltage yaiwanzova mukati me 0.1-0.2V inotenderwa kutarisa mabhatiri. Kune AC voltage yaive pamusoro penzvimbo-yakayerwa 127V pane yekubuda yaive 121V maererano nemamita angu akanaka. Izvo hazvisi izvo zvisina chokwadi, izvo zvinogona kuve nengozi kana iwe uri kuita sarudzo zvichienderana nekuverenga ikoko.

Zvinoenderana nekumwe kuyedza kwakaitwa nemainjiniya kuKeysight (keysight.com/blogs), maitiro ekutadza pamamita akachipa anowanzo kuve nenjodzi kana atadza{1}}pasina dziviriro yearc, kushoma fusing, uye maPCB anongonyura pane kutadza zvisina njodzi. Ongororo yavo yekubvarura yakaratidza kunaka kwekuvaka kwemukati kwaisazopasa chero chepamutemo chekuchengetedza chitupa.

Mamwe mamita ikozvino ane Bluetooth kana USB yekubatanidza yekutora data. Handisati ndaona izvi zvichibatsira pabasa rangu, asi ndiri kuona zvikumbiro pazvingave zvakakosha-nguva yakareba-kutarisisa, kuzviedza nemaoko, chinhu ichocho. Iyo Brymen BM869s ine optical USB (kwete modhi imwe chete yandinayo asi ivo vanogadzira imwe) iyo inonyanya kubatsira nekuti Optical isolation zvinoreva kuti hapana pasi zvishwe kana nyaya dzeruzha paunenge uchibatana nekombuta.

Kana iwe uchida kutema matanda, kune yakatsaurirwa matanda multimeters akagadzirirwa chaizvo chinangwa ichocho. Iyo Fluke 289 semuenzaniso inogona kuchengeta zviuru zvekuverenga netimestamps. Mutengo wakaita se$500+ zvisinei kuti hausi wekutenga zvekufunga.

multimeter

Kune mumwe munhu achangopinda mune zvemagetsi: UNI-T UT61E kana zvakafanana ~$70-80 renji yemamita. Inoita kuti iwe ugone kunyatso dzidza uye haufe kana ukaongorora netsaona chimwe chinhu chisina kunaka (chine zvine musoro kuchengetedza maficha). Sevha mari yezvishandiso zviri nani senge yakanaka solder iron kana chiyero.

Zvekugadzirisa zvemagetsi zvehunyanzvi: Brymen BM869s kana Fluke 115/117. Ose ari maviri akapoteredza $180-220. Iyo Brymen ine mamwe maficha, iyo Fluke yakanyanya rugged uye ine nani garandi rutsigiro. Haikwanise kunyatsoenda zvisizvo kana.

Yebasa reindasitiri / remagetsi: Fluke 87V kana yakaenzana. $400-450 asi yakakosha kune iyo yekuchengetedza zviyero uye kusimba. Ini handingadhure kunze uku nekuti mhedzisiro yekutadza kwemamita yakanyanya kuoma.

Zvemotokari: Inoda yakanaka AC voltage kurongeka (ye sensors), kukurumidza sampling, uye Hz/basa kutenderera kuyerwa. Iyo Fluke 88V yakakurumbira asi inodhura. Pane mota-mamita chaiwo kubva kumakambani akaita seSnap{4}}asi anotodhura uye pamwe haana kukosha kunze kwekunge uri-nguva yakazara auto tech.

Hapana munhu anoda Keysight 34461A benchtop mita kunze kwekunge iwe uri kuita metrology kana chaiyo calibration basa. Iwo anotanga pa$900+ uye hongu akanyatsojeka (± 0.004% DC V) asi hazvigoneke pakugadzirisa zvakajairika uye kugadzirisa matambudziko. Ini ndinotaura izvi nekuti ndakaona vanhu pamaforamu vachivakurudzira kune vanotanga izvo zvinongopusa.

Ndizvo zvakawanda zvandinofunga zvakakosha kana uchitora multimeter. Handina kuvhara maoscilloscope ekubatanidza maficha kana mamwe emhando dzezviyero zvemhando yepamusoro (inductance, capacitance pamusoro pekuyedzwa kwekutanga) nekuti kutaura chokwadi handishandise izvo zvakakwana kuti ndive nemafungiro akasimba. Tenga chimwe chinhu kubva kumhando yepamutemo ine chaiyo yekuchengetedza zvitupa, ita shuwa kuti kuenderera mberi beeper kuri kukurumidza, uye pamwe ungave wakanaka.

Haa uye chinhu chekupedzisira-chengeta mabhatiri akasara aripo. Mamita mazhinji anoshandisa 9V asi mamwe mamodheru (mamwe maFlukes, semuenzaniso) anodalithium CR1/3N bhatiriizvo zvisina kufanana. Kuita kuti mita yako ife pakati pebasa rekugadzirisa zvinogumbura, saka ingotora ma spares maviri paunoraira mita.