{"id":1685,"date":"2015-02-25T18:06:35","date_gmt":"2015-02-25T16:06:35","guid":{"rendered":"http:\/\/www.dainile.lt\/?p=1685"},"modified":"2022-05-24T14:57:41","modified_gmt":"2022-05-24T12:57:41","slug":"arduino-sroves-matavimas","status":"publish","type":"post","link":"https:\/\/www.dclabs.lt\/dainiaus\/arduino-sroves-matavimas\/","title":{"rendered":"Arduino srov\u0117s matavimas"},"content":{"rendered":"

Prisireik\u0117 \u010dia man matuoti srov\u0119 su Arduino. \u010cia b\u016bt\u0173 didesnio projekto dalis, taigi, i\u0161mas\u010diau tokius variantus – holodaviklinis, rezistorius (\u0161untas), rit\u0117. Vienok, tame daikte, kuriame bus matuojama srov\u0117, gali b\u016bti daug elektromagnetinio trukd\u017eio, kaip jis paveiks holodaviklini matavim\u0105 – ne\u017einau. Gal niekaip, o gal ka\u017ekaip, neteko daryt… Su rite irgi niuansas – radau vien\u0105, kuri kaip ir tikt\u0173, bet ne lauko instaliacijai (nu kad ir po kapotu, bet vistiek, dulk\u0117s, dr\u0117gm\u0117), o ir maitinimas dvipolis. Ir i\u0161\u0117jimas dvipolis. Turb\u016bt tam, kad krovimas pliuse, o i\u0161krovimas minuse indikuojamas. O atspariausias trukd\u017eiams butu \u0161untas, bet, krovimo srove gali buti 50-70A, tai \u0161unta jau\u010diu nor\u0117sis jamt kad bent 100A laikyt\u0173. Bet \u0161untiniam sprendime minusas – \u0161iluma. Kaip visada, \u017eiupsnelis teorijos. Bet kur\u012f \u0161unt\u0105 galima laikyti rezistoriumi, su jo var\u017ea, ir b\u016btinai – \u0161ilimu. O \u0161untui kaistant – kei\u010diasi jo var\u017ea. D\u0117l to, rekomenduojama maksimali \u0161unto temperat\u016bra 80\u00b0 C, o \u012fprastai jie tur\u0117t\u0173 dirbti 40\u00b0 C\u00a0 – 60\u00b0 C\u00a0 ribose. Pagal IEEE standartus ir rekomendacijas, pastoviam veikimui, \u0161untas netur\u0117t\u0173 b\u016bti apkraunamas didesne nei 2\/3 vardine srove. Mano atveju maksimali \u012fmanoma srov\u0117 gali b\u016bti 70A, taigi, \u0161unto nominali srov\u0117 tur\u0117t\u0173 b\u016bti bent 105A. Kad b\u016bt\u0173 dar patikimiau, u\u017esisakiau 200A \u0161untuk\u0105<\/a>. Tur\u0117t\u0173 b\u016bti penktadien\u012f (2015.02.27). Taigi, tikiuosi jis niekada nepasieks mirtina laikomos 145\u00b0 C\u00a0 temperat\u016bros. Esant galimybei rekomenduoju \u0161unt\u0105 montuoti ventiliuojamoje vietoje (tiks ir variklio ventiliatorius, ir \u0161iaip laisvai lakstantis oro srautas). Srov\u0117s matavimo laidukai (\u012f Arduino) tur\u0117t\u0173 b\u016bti kuo trumpesni – ilgas laidas sukuria didesn\u012f \u012ftampos kritim\u0105, o \u0161ituo atveju \u012ftampa ir taip ma\u017ea. Taigis, dabar bandykim imituoti toki\u0105 situacij\u0105, kai lauke kar\u0161ta (daugiau 25\u00b0 C), tarkim 50\u00b0 C (ma\u017eai tik\u0117tina, bet jei \u0161untas sumontuotas prie variklio…), pasirinktas \u0161untas – 200A ir 60 mV. Skai\u010diuojam:<\/p>\n

P\u0161 = Pmax\u00a0\u22c5 0,667 \u22c5 (1-(T-25\u00b0 C )\/100\u00b0 C );<\/p>\n

\u010dia: P\u0161 – maksimali \u0161ilumin\u0117 galia, Pmax – maksimali \u0161unto galia, T – temperat\u016bra (50\u00b0 C), 0,667 – atsargos koeficientas.<\/p>\n

P\u0161 = (200A \u22c5 0,667\u22c5 0,06 mV) \u22c5 (1 – (50-25)\/100) = 8W \u22c5 (1-0,25) = 6W<\/p>\n

Taigi, turim, kad \u0161untas \u0161ils kaip 6W kaitinimo tenukas \ud83d\ude42<\/p>\n

Imaks = SQRT (P\u0161\/R),<\/p>\n

\u010dia Imaks – maksimali leistina srov\u0117 prie 50\u00b0 C, R – \u0161unto var\u017ea.<\/p>\n

\u0160unto var\u017ea pagal Omo d\u0117sn\u012f – R = U\/I, R = 0,06 \/ 200 =\u00a00,0003\u00a0\u03a9.<\/p>\n

Imaks = SQRT (6\/0,0003) = 141,42 A<\/p>\n

taigi, \u0161untas saugiai, nevir\u0161ydamas 50\u00b0 C temperat\u016bros, gali per save leisti 141,42 A srov\u0119. O m\u016bs\u0173 atveju srov\u0117 tur\u0117t\u0173 b\u016bti dar ma\u017eesn\u0117. Kadangi telpam \u012f ribas – belieka sulaukti \u0161unto ir padaryti real\u0173 bandym\u0105 :). Su rastu 0,22 \u03a9 rezitorium viskas kaip ir veikia. Programa nesud\u0117tinga, prisegu \u010dia<\/a>. Schema irgi paprasta, principas toks:<\/p>\n

\"volt\"<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

Prisireik\u0117 \u010dia man matuoti srov\u0119 su Arduino. \u010cia b\u016bt\u0173 didesnio projekto dalis, taigi, i\u0161mas\u010diau tokius variantus – holodaviklinis, rezistorius (\u0161untas), rit\u0117. Vienok, tame daikte, kuriame bus matuojama srov\u0117, gali b\u016bti daug elektromagnetinio trukd\u017eio, kaip jis paveiks holodaviklini matavim\u0105 – ne\u017einau. Gal niekaip, o gal ka\u017ekaip, neteko daryt… Su rite irgi niuansas – radau vien\u0105, kuri…<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4],"tags":[],"class_list":["post-1685","post","type-post","status-publish","format-standard","hentry","category-elektronika"],"_links":{"self":[{"href":"https:\/\/www.dclabs.lt\/dainiaus\/wp-json\/wp\/v2\/posts\/1685","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.dclabs.lt\/dainiaus\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.dclabs.lt\/dainiaus\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.dclabs.lt\/dainiaus\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.dclabs.lt\/dainiaus\/wp-json\/wp\/v2\/comments?post=1685"}],"version-history":[{"count":15,"href":"https:\/\/www.dclabs.lt\/dainiaus\/wp-json\/wp\/v2\/posts\/1685\/revisions"}],"predecessor-version":[{"id":4368,"href":"https:\/\/www.dclabs.lt\/dainiaus\/wp-json\/wp\/v2\/posts\/1685\/revisions\/4368"}],"wp:attachment":[{"href":"https:\/\/www.dclabs.lt\/dainiaus\/wp-json\/wp\/v2\/media?parent=1685"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.dclabs.lt\/dainiaus\/wp-json\/wp\/v2\/categories?post=1685"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.dclabs.lt\/dainiaus\/wp-json\/wp\/v2\/tags?post=1685"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}