{"id":784,"date":"2012-06-11T18:39:36","date_gmt":"2012-06-11T17:39:36","guid":{"rendered":"http:\/\/www.marallo.sk\/?p=784"},"modified":"2012-06-11T18:39:36","modified_gmt":"2012-06-11T17:39:36","slug":"vypocet-bocnika-k-ampermetru","status":"publish","type":"post","link":"https:\/\/www.marallo.sk\/?p=784","title":{"rendered":"V\u00fdpo\u010det bo\u010dn\u00edka k amp\u00e9rmetru&#8230;"},"content":{"rendered":"<p>Vyr\u00e1bal som nap\u00e1jac\u00ed zdroj, a na predn\u00fd panel som chcel da\u0165 amp\u00e9rmeter. Niekde v \u0161upl\u00edku som na\u0161iel ak\u00e9si panelov\u00e9 meradlo, a vznikol probl\u00e9m ako k nemu vypo\u010d\u00edta\u0165 bo\u010dn\u00edk. Zalistoval som v literat\u00fare, a na\u0161iel som tak\u00fdto vzor\u010dek:<!--more--><\/p>\n<p><span style=\"color: #ff9900;\">Rb =\u00a0\u00a0<span style=\"text-decoration: underline;\">\u00a0 \u00a0 Ia \u00a0 \u00a0 <\/span> \u00a0\u00a0x\u00a0 Ra<\/span><br \/>\n<span style=\"color: #ff9900;\"> \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0Ib<\/span><\/p>\n<p><span style=\"color: #3366ff;\">Ra \u2013 odpor amp\u00e9rmetra (zmeriame ohmmetrom)<\/span><br \/>\n<span style=\"color: #3366ff;\"> Rb \u2013 odpor bo\u010dn\u00edka (nepozn\u00e1me, sna\u017e\u00edme sa ho vypo\u010d\u00edta\u0165)<\/span><br \/>\n<span style=\"color: #3366ff;\"> Ia \u2013 pr\u00fad ktor\u00fd m\u00e1 tiec\u0165 cez amp\u00e9rmeter pri plnom vych\u00fdlen\u00ed ru\u010di\u010dky (je nap\u00edsan\u00fd na panelovom meradle)<\/span><br \/>\n<span style=\"color: #3366ff;\"> Ib \u2013 pr\u00fad ktor\u00fd m\u00e1 tiec\u0165 cez bo\u010dn\u00edk (vypo\u010d\u00edtame Ib = I \u2013 Ia)<\/span><\/p>\n<p><a href=\"http:\/\/www.marallo.sk\/wp-content\/\/bocnik.gif\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-785\" title=\"bocnik\" src=\"http:\/\/www.marallo.sk\/wp-content\/\/bocnik.gif\" alt=\"\" width=\"300\" height=\"200\" \/><\/a><\/p>\n<p>Pr\u00edklad:<br \/>\nNa\u0161li sme na smetisku panelov\u00e9 meradlo 1mA, a zmerali sme \u017ee m\u00e1 vn\u00fatorn\u00fd odpor 192 Ohmov. Chceme ho da\u0165 do zdroja, ktor\u00fd vie doda\u0165 maxim\u00e1lne 5 Amp\u00e9rov&#8230;<\/p>\n<p><span style=\"color: #ff9900;\">Rb = <span style=\"text-decoration: underline;\"> \u00a0 \u00a0 \u00a0Ia \u00a0 \u00a0 <\/span> \u00a0\u00a0x Ra = <span style=\"text-decoration: underline;\">0,001<\/span> x 192 = 0,0384 Ohm<\/span><br \/>\n<span style=\"color: #ff9900;\"> \u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0Ib\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0 \u00a0\u00a0\u00a0\u00a0\u00a0 4,999<\/span><\/p>\n<p>Vysklad\u00e1me teda bo\u010dn\u00edk o hodnote 0,0384 Ohm. Ale na ak\u00fd v\u00fdkon by mal by\u0165 aby nezadymil?<br \/>\nVypo\u010d\u00edtame ho jednoducho:<\/p>\n<p><span style=\"color: #ff9900;\">P = U x I<\/span><\/p>\n<p><span style=\"color: #3366ff;\">P \u2013 v\u00fdkon premenen\u00fd na teplo v bo\u010dn\u00edka<\/span><br \/>\n<span style=\"color: #3366ff;\"> U \u2013 Nap\u00e4tie ktor\u00e9 je na bo\u010dn\u00edka pri plnom vych\u00fdlen\u00ed ru\u010di\u010dky<\/span><br \/>\n<span style=\"color: #3366ff;\"> I \u2013 pr\u00fad te\u010d\u00faci cez bo\u010dn\u00edk pri plnom vych\u00fdlen\u00ed<\/span><\/p>\n<p>Pr\u00fad te\u010d\u00faci cez bo\u010dn\u00edk pozn\u00e1me, ale ako zist\u00edme ak\u00e9 nap\u00e1tie bude na bo\u010dn\u00edku pri plnom vych\u00fdlen\u00ed? Jednoducho si ho vypo\u010d\u00edtame pomocou Ohmovho z\u00e1kona:<\/p>\n<p><span style=\"color: #ff9900;\">U = I x R<\/span><\/p>\n<p>Teda v na\u0161om pr\u00edklade bude na bo\u010dn\u00edku nap\u00e4tie:<\/p>\n<p><span style=\"color: #ff9900;\">U = 4,999 x 0,0384 = 0,192 Voltu<\/span><\/p>\n<p>Ke\u010f u\u017e pozn\u00e1me nap\u00e4tie, po\u010fme vypo\u010d\u00edta\u0165 ten v\u00fdkon:<\/p>\n<p><span style=\"color: #ff9900;\">P = U x I = 0,192 x 4,999 = 0,959 Wattu.<\/span><\/p>\n<p>To je v\u0161etko \u010do potrebujeme vedie\u0165, a u\u017e treba len chyti\u0165 p\u00e1jkova\u010dku a pusti\u0165 sa do pr\u00e1ce. Viem \u017ee tieto v\u00fdpo\u010dty sa u\u010dia sn\u00e1\u010f u\u017e na z\u00e1kladnej \u0161kole, no kto by si to pam\u00e4tal. Mal\u00fd prieskum uk\u00e1zal \u017ee si to veru nepam\u00e4t\u00e1 nikto&#8230;<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Vyr\u00e1bal som nap\u00e1jac\u00ed zdroj, a na predn\u00fd panel som chcel da\u0165 amp\u00e9rmeter. Niekde v \u0161upl\u00edku som na\u0161iel ak\u00e9si panelov\u00e9 meradlo, a vznikol probl\u00e9m ako k nemu vypo\u010d\u00edta\u0165 bo\u010dn\u00edk. Zalistoval som v literat\u00fare, a na\u0161iel som tak\u00fdto vzor\u010dek:<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_links_to":"","_links_to_target":""},"categories":[3,1,11],"tags":[],"class_list":["post-784","post","type-post","status-publish","format-standard","hentry","category-ham","category-nezaradene","category-all"],"views":4581,"_links":{"self":[{"href":"https:\/\/www.marallo.sk\/index.php?rest_route=\/wp\/v2\/posts\/784"}],"collection":[{"href":"https:\/\/www.marallo.sk\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.marallo.sk\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.marallo.sk\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.marallo.sk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=784"}],"version-history":[{"count":14,"href":"https:\/\/www.marallo.sk\/index.php?rest_route=\/wp\/v2\/posts\/784\/revisions"}],"predecessor-version":[{"id":799,"href":"https:\/\/www.marallo.sk\/index.php?rest_route=\/wp\/v2\/posts\/784\/revisions\/799"}],"wp:attachment":[{"href":"https:\/\/www.marallo.sk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=784"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.marallo.sk\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=784"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.marallo.sk\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=784"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}