P\u0159\u00edru\u010dka pro elektrotechniky pro vyd\u00e1n\u00ed NEC 2023.<\/p>\n\n\n\n
NEC 240.87 je odd\u00edl p\u0159edpisu, kter\u00fd se t\u00fdk\u00e1 N\u00e1rodn\u00ed elektrotechnick\u00e9 p\u0159edpisy (NEC)<\/a>), kter\u00e1 vy\u017eaduje metody sni\u017eov\u00e1n\u00ed energie oblouku u jisti\u010d\u016f o jmenovit\u00e9m proudu 1200 A nebo vy\u0161\u0161\u00edm. Energie oblouku je mno\u017estv\u00ed tepla a sv\u011btla, kter\u00e9 vznik\u00e1 v d\u016fsledku elektrick\u00fd oblouk<\/a> porucha, kter\u00e1 m\u016f\u017ee zp\u016fsobit v\u00e1\u017en\u00e9 \u0161kody na za\u0159\u00edzen\u00ed a person\u00e1lu. Metody sni\u017eov\u00e1n\u00ed energie oblouku jsou navr\u017eeny tak, aby zkr\u00e1tily dobu trv\u00e1n\u00ed a intenzitu obloukov\u00e9 poruchy, a t\u00edm minimalizovaly potenci\u00e1ln\u00ed nebezpe\u010d\u00ed.<\/p>\n\n\n\n Norma NEC 240.87 je d\u016fle\u017eit\u00e1, proto\u017ee \u0159e\u0161\u00ed z\u00e1va\u017en\u00fd bezpe\u010dnostn\u00ed probl\u00e9m v oblasti elektrick\u00e9 syst\u00e9my<\/a>. K obloukov\u00fdm poruch\u00e1m m\u016f\u017ee doj\u00edt z r\u016fzn\u00fdch p\u0159\u00ed\u010din, nap\u0159\u00edklad v d\u016fsledku poruchy izolace, voln\u00e9 spoje,<\/a> ciz\u00ed p\u0159edm\u011bty nebo lidsk\u00e1 chyba. P\u0159i poru\u0161e elektrick\u00e9ho oblouku m\u016f\u017ee vzniknout teplota a\u017e 35 000 stup\u0148\u016f Fahrenheita, kter\u00e1 m\u016f\u017ee roztavit kov, zap\u00e1lit ho\u0159lav\u00e9 materi\u00e1ly a zp\u016fsobit v\u00e1\u017en\u00e9 pop\u00e1leniny a zran\u011bn\u00ed. Obloukov\u00e9 poruchy mohou tak\u00e9 vytv\u00e1\u0159et tlakov\u00e9 vlny, kter\u00e9 mohou protrhnout u\u0161n\u00ed bub\u00ednky, po\u0161kodit pl\u00edce a rozb\u00edt okna. Podle N\u00e1rodn\u00ed asociace po\u017e\u00e1rn\u00ed ochrany (NFPA) maj\u00ed obloukov\u00e9 poruchy ve Spojen\u00fdch st\u00e1tech ro\u010dn\u011b na sv\u011bdom\u00ed v\u00edce ne\u017e 2 000 zran\u011bn\u00ed a 400 \u00famrt\u00ed.<\/p>\n\n\n\n Norma NEC 240.87 vy\u017eaduje u jisti\u010d\u016f se jmenovit\u00fdm proudem 1200 A nebo vy\u0161\u0161\u00edm jednu z n\u00e1sleduj\u00edc\u00edch metod sn\u00ed\u017een\u00ed energie oblouku:<\/p>\n\n\n\n Pro spln\u011bn\u00ed po\u017eadavk\u016f normy NEC 240.87 by m\u011bli elektrotechnici postupovat podle n\u00e1sleduj\u00edc\u00edch krok\u016f:<\/p>\n\n\n\n NEC 240.87 je \u010d\u00e1st p\u0159edpisu, kter\u00e1 vy\u017eaduje metody redukce energie oblouku u jisti\u010d\u016f o jmenovit\u00e9m proudu 1200 A nebo vy\u0161\u0161\u00edm. Jeho c\u00edlem je zv\u00fd\u0161it bezpe\u010dnost elektrick\u00fdch syst\u00e9m\u016f a sni\u017euj\u00ed riziko vzniku elektrick\u00e9ho oblouku<\/a> z\u00e1vady. Elektrik\u00e1\u0159i by m\u011bli b\u00fdt sezn\u00e1meni s metodami sni\u017eov\u00e1n\u00ed energie oblouku a s kroky pro dosa\u017een\u00ed souladu s NEC 240.87.<\/p>","protected":false},"excerpt":{"rendered":" A Guide for Electrical Professionals for the 2023 NEC edition. What is NEC 240.87? NEC 240.87 is a code section in the National Electrical Code (NEC) that requires arc energy reduction methods for circuit breakers rated at 1200 amps or higher. Arc energy is the amount of heat and light produced by an electrical arc […]<\/p>\n","protected":false},"author":8,"featured_media":4267,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_mbp_gutenberg_autopost":false,"_pgmb_is_evergreen":true,"_pgmb_ap_template_id":0,"iawp_total_views":218,"footnotes":""},"categories":[4],"tags":[],"class_list":["post-4266","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-electrical"],"acf":[],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\tPro\u010d je NEC 240.87 d\u016fle\u017eit\u00e1?<\/h2>\n\n\n\n
Jak\u00e9 metody sni\u017eov\u00e1n\u00ed energie oblouku vy\u017eaduje norma NEC 240.87?<\/h2>\n\n\n\n
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Jak vyhov\u011bt NEC 240.87?<\/h2>\n\n\n\n
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