{"id":21209,"date":"2026-01-06T00:10:09","date_gmt":"2026-01-05T16:10:09","guid":{"rendered":"https:\/\/viox.com\/?p=21209"},"modified":"2026-01-06T00:17:14","modified_gmt":"2026-01-05T16:17:14","slug":"electrical-derating-temperature-altitude-grouping-factors","status":"publish","type":"post","link":"https:\/\/test.viox.com\/cs\/electrical-derating-temperature-altitude-grouping-factors\/","title":{"rendered":"Hlavn\u00ed pr\u016fvodce sn\u00ed\u017een\u00edm elektrick\u00e9ho v\u00fdkonu: Teplota, nadmo\u0159sk\u00e1 v\u00fd\u0161ka a koeficienty seskupen\u00ed"},"content":{"rendered":"<div class=\"product-intro\">\n<h2>Pochopen\u00ed elektrick\u00e9ho sn\u00ed\u017een\u00ed jmenovit\u00e9ho v\u00fdkonu: Pro\u010d je to d\u016fle\u017eit\u00e9 pro bezpe\u010dn\u00e9 instalace<\/h2>\n<p>Elektrick\u00e9 sn\u00ed\u017een\u00ed jmenovit\u00e9ho v\u00fdkonu je systematick\u00e9 sn\u00ed\u017een\u00ed proudov\u00e9 zat\u00ed\u017eitelnosti vodi\u010de (ampacity) s c\u00edlem zohlednit skute\u010dn\u00e9 instala\u010dn\u00ed podm\u00ednky, kter\u00e9 se odchyluj\u00ed od standardn\u00edch testovac\u00edch prost\u0159ed\u00ed. Kdy\u017e kabely pracuj\u00ed p\u0159i vysok\u00fdch teplot\u00e1ch, ve vysok\u00fdch nadmo\u0159sk\u00fdch v\u00fd\u0161k\u00e1ch nebo jsou sv\u00e1z\u00e1ny s jin\u00fdmi vodi\u010di, jejich schopnost odv\u00e1d\u011bt teplo se v\u00fdrazn\u011b sni\u017euje. Bez \u0159\u00e1dn\u00fdch v\u00fdpo\u010dt\u016f sn\u00ed\u017een\u00ed jmenovit\u00e9ho v\u00fdkonu \u010del\u00ed instalace v\u00e1\u017en\u00fdm rizik\u016fm: p\u0159ed\u010dasn\u00e9 selh\u00e1n\u00ed izolace, <a href=\"https:\/\/test.viox.com\/cs\/mcb\/\">jisti\u010d<\/a> obt\u011b\u017euj\u00edc\u00ed vyp\u00edn\u00e1n\u00ed, nebezpe\u010d\u00ed po\u017e\u00e1ru a nesoulad s normami NEC \u010dl\u00e1nek 310.15 a IEC 60364-5-52.<\/p>\n<p>Pro B2B profesion\u00e1ly instaluj\u00edc\u00ed <a href=\"https:\/\/test.viox.com\/cs\/rccb-ev-charging-type-b-vs-type-f-vs-type-ev\/\">infrastrukturu pro nab\u00edjen\u00ed elektromobil\u016f<\/a>, sol\u00e1rn\u00ed pole nebo pr\u016fmyslov\u00e9 elektrick\u00e9 syst\u00e9my, pochopen\u00ed faktor\u016f sn\u00ed\u017een\u00ed jmenovit\u00e9ho v\u00fdkonu nen\u00ed voliteln\u00e9 \u2013 je to z\u00e1kladn\u00ed po\u017eadavek pro bezpe\u010dnost, soulad s p\u0159edpisy a \u017eivotnost syst\u00e9mu. Tato hlavn\u00ed p\u0159\u00edru\u010dka poskytuje technick\u00fd r\u00e1mec, kter\u00fd pot\u0159ebujete k v\u00fdpo\u010dtu p\u0159esn\u00fdch faktor\u016f sn\u00ed\u017een\u00ed jmenovit\u00e9ho v\u00fdkonu a spr\u00e1vn\u00e9mu dimenzov\u00e1n\u00ed vodi\u010d\u016f pro jak\u00fdkoli sc\u00e9n\u00e1\u0159 instalace.<\/p>\n<figure style=\"text-align: center; margin: 20px 0;\"><img decoding=\"async\" style=\"max-width: 100%; height: auto;\" src=\"https:\/\/img.viox.com\/High-temperature-electrical-installation-showing-VIOX-circuit-protection-equipment-operating-in-extreme-ambient-conditions-requiring-temperature-derating-factors.webp\" alt=\"High-temperature electrical installation showing VIOX circuit protection equipment operating in extreme ambient conditions requiring temperature derating factors\" \/><figcaption style=\"font-style: italic; color: #555; margin-top: 8px;\">Vysokoteplotn\u00ed elektrick\u00e1 instalace zobrazuj\u00edc\u00ed za\u0159\u00edzen\u00ed pro ochranu obvod\u016f VIOX pracuj\u00edc\u00ed v extr\u00e9mn\u00edch okoln\u00edch podm\u00ednk\u00e1ch vy\u017eaduj\u00edc\u00edch faktory sn\u00ed\u017een\u00ed jmenovit\u00e9ho v\u00fdkonu v z\u00e1vislosti na teplot\u011b.<\/figcaption><\/figure>\n<h2>Odd\u00edl 1: Faktory sn\u00ed\u017een\u00ed jmenovit\u00e9ho v\u00fdkonu v z\u00e1vislosti na teplot\u011b<\/h2>\n<h3>Korekce okoln\u00ed teploty vzduchu<\/h3>\n<p><strong>Standardn\u00ed referen\u010dn\u00ed podm\u00ednky<\/strong> p\u0159edpokl\u00e1daj\u00ed okoln\u00ed teplotu 30 \u00b0C (86 \u00b0F) pro kabely instalovan\u00e9 ve vzduchu. Kdy\u017e skute\u010dn\u00e9 teploty p\u0159ekro\u010d\u00ed tuto z\u00e1kladn\u00ed hodnotu, ampacita vodi\u010de se mus\u00ed sn\u00ed\u017eit podle tabulky 310.15(B)(1) NEC nebo tabulky B.52.14 IEC 60364-5-52.<\/p>\n<p><strong>Kritick\u00e9 faktory sn\u00ed\u017een\u00ed jmenovit\u00e9ho v\u00fdkonu v z\u00e1vislosti na teplot\u011b pro b\u011b\u017en\u00e9 typy izolace:<\/strong><\/p>\n<table style=\"border-collapse: collapse; width: 100%; margin-bottom: 20px;\" border=\"1\" cellpadding=\"8\">\n<thead>\n<tr style=\"background-color: #f2f2f2;\">\n<th>Okoln\u00ed teplota<\/th>\n<th>PVC izolace (70 \u00b0C)<\/th>\n<th>XLPE\/EPR izolace (90 \u00b0C)<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>30 \u00b0C (86 \u00b0F)<\/td>\n<td>1.00<\/td>\n<td>1.00<\/td>\n<\/tr>\n<tr>\n<td>35 \u00b0C (95 \u00b0F)<\/td>\n<td>0.94<\/td>\n<td>0.96<\/td>\n<\/tr>\n<tr>\n<td>40 \u00b0C (104 \u00b0F)<\/td>\n<td>0.87<\/td>\n<td>0.91<\/td>\n<\/tr>\n<tr>\n<td>45 \u00b0C (113 \u00b0F)<\/td>\n<td>0.79<\/td>\n<td>0.87<\/td>\n<\/tr>\n<tr>\n<td>50 \u00b0C (122 \u00b0F)<\/td>\n<td>0.71<\/td>\n<td>0.82<\/td>\n<\/tr>\n<tr>\n<td>55 \u00b0C (131 \u00b0F)<\/td>\n<td>0.61<\/td>\n<td>0.76<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><strong>Aplikace v re\u00e1ln\u00e9m sv\u011bt\u011b:<\/strong> Sol\u00e1rn\u00ed instalace na komer\u010dn\u00edch st\u0159ech\u00e1ch b\u011b\u017en\u011b za\u017e\u00edvaj\u00ed okoln\u00ed teploty 50\u201355 \u00b0C v l\u00e9t\u011b. M\u011bd\u011bn\u00fd vodi\u010d THHN 10 AWG dimenzovan\u00fd na 40 A p\u0159i 30 \u00b0C klesne na pouh\u00fdch <strong>32,8 A<\/strong> (40 A \u00d7 0,82) p\u0159i 50 \u00b0C \u2013 sn\u00ed\u017een\u00ed o 18 %, kter\u00e9 by mohlo p\u0159et\u00ed\u017eit poddimenzovan\u00e9 vodi\u010de.<\/p>\n<h3>Korekce teploty p\u016fdy pro podzemn\u00ed kabely<\/h3>\n<p>Podzemn\u00ed instalace \u010del\u00ed r\u016fzn\u00fdm tepeln\u00fdm v\u00fdzv\u00e1m. Normy IEC 60287 a NEC odkazuj\u00ed na <strong>teplotu p\u016fdy 20 \u00b0C (68 \u00b0F)<\/strong> jako z\u00e1kladn\u00ed hodnotu pro zakopan\u00e9 kabely.<\/p>\n<p><strong>Faktory korekce teploty p\u016fdy:<\/strong><\/p>\n<table style=\"border-collapse: collapse; width: 100%; margin-bottom: 20px;\" border=\"1\" cellpadding=\"8\">\n<thead>\n<tr style=\"background-color: #f2f2f2;\">\n<th>Teplota p\u016fdy<\/th>\n<th>Korek\u010dn\u00ed faktor (v\u0161echny typy izolace)<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>20 \u00b0C (68 \u00b0F)<\/td>\n<td>1.00<\/td>\n<\/tr>\n<tr>\n<td>25 \u00b0C (77 \u00b0F)<\/td>\n<td>0.96<\/td>\n<\/tr>\n<tr>\n<td>30 \u00b0C (86 \u00b0F)<\/td>\n<td>0.92<\/td>\n<\/tr>\n<tr>\n<td>35 \u00b0C (95 \u00b0F)<\/td>\n<td>0.87<\/td>\n<\/tr>\n<tr>\n<td>40 \u00b0C (104 \u00b0F)<\/td>\n<td>0.82<\/td>\n<\/tr>\n<tr>\n<td>45 \u00b0C (113 \u00b0F)<\/td>\n<td>0.77<\/td>\n<\/tr>\n<tr>\n<td>50 \u00b0C (122 \u00b0F)<\/td>\n<td>0.71<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><strong>Hloubka zakop\u00e1n\u00ed tak\u00e9 ovliv\u0148uje tepeln\u00fd v\u00fdkon.<\/strong> Kabely zakopan\u00e9 v hloubce 80 cm maj\u00ed p\u0159ibli\u017en\u011b o 4 % lep\u0161\u00ed odvod tepla ne\u017e kabely v hloubce 50 cm, co\u017e vede ke korek\u010dn\u00edmu faktoru <strong>0.96<\/strong> , kter\u00fd \u010d\u00e1ste\u010dn\u011b kompenzuje vysok\u00e9 teploty p\u016fdy.<\/p>\n<h3>\u00da\u010dinky kontaktu s tepelnou izolac\u00ed<\/h3>\n<p>Kdy\u017e kabely proch\u00e1zej\u00ed tepelnou izolac\u00ed nebo jsou j\u00ed obklopeny (b\u011b\u017en\u00e9 u pr\u016fnik\u016f budovami), odvod tepla se v\u00fdrazn\u011b zhor\u0161uje. Podle NEC 310.15(A)(3) a IEC 60364-5-52:<\/p>\n<ul>\n<li><strong>Kabely dot\u00fdkaj\u00edc\u00ed se tepeln\u00e9 izolace po dobu \u2264100 mm:<\/strong> Pou\u017eijte faktor <strong>0.89<\/strong><\/li>\n<li><strong>Kabely obklopen\u00e9 izolac\u00ed po dobu &gt;500 mm:<\/strong> Pou\u017eijte faktor <strong>0.50<\/strong> (sn\u00ed\u017een\u00ed o 50 %)<\/li>\n<li><strong>Kruhov\u00e9 koncov\u00e9 obvody v izolovan\u00fdch prostorech:<\/strong> M\u016f\u017ee vy\u017eadovat zv\u011bt\u0161en\u00ed pr\u016f\u0159ezu z 2,5 mm\u00b2 na 4 mm\u00b2<\/li>\n<\/ul>\n<p>Pro <a href=\"https:\/\/test.viox.com\/cs\/residential-circuit-breakers-vs-industrial-circuit-breakers\/\">reziden\u010dn\u00ed a komer\u010dn\u00ed aplikace jisti\u010d\u016f<\/a>, tento \u010dasto p\u0159ehl\u00ed\u017een\u00fd faktor zp\u016fsobuje v\u00fdznamn\u00e9 chyby v dimenzov\u00e1n\u00ed.<\/p>\n<figure style=\"text-align: center; margin: 20px 0;\"><img decoding=\"async\" style=\"max-width: 100%; height: auto;\" src=\"https:\/\/img.viox.com\/Technical-diagram-comparing-heat-dissipation-in-different-cable-installation-methods-with-corresponding-derating-factors-for-thermal-insulation-contact.webp\" alt=\"Technical diagram comparing heat dissipation in different cable installation methods with corresponding derating factors for thermal insulation contact\" \/><figcaption style=\"font-style: italic; color: #555; margin-top: 8px;\">Technick\u00fd diagram porovn\u00e1vaj\u00edc\u00ed odvod tepla u r\u016fzn\u00fdch metod instalace kabel\u016f s odpov\u00eddaj\u00edc\u00edmi faktory sn\u00ed\u017een\u00ed jmenovit\u00e9ho v\u00fdkonu pro kontakt s tepelnou izolac\u00ed.<\/figcaption><\/figure>\n<h2>Odd\u00edl 2: Faktory sn\u00ed\u017een\u00ed jmenovit\u00e9ho v\u00fdkonu v z\u00e1vislosti na nadmo\u0159sk\u00e9 v\u00fd\u0161ce<\/h2>\n<h3>Pro\u010d nadmo\u0159sk\u00e1 v\u00fd\u0161ka ovliv\u0148uje elektrick\u00e9 za\u0159\u00edzen\u00ed<\/h3>\n<p>V nadmo\u0159sk\u00fdch v\u00fd\u0161k\u00e1ch nad 1 000 metr\u016f (3 300 stop), <strong>sn\u00ed\u017een\u00fd atmosf\u00e9rick\u00fd tlak<\/strong> sni\u017euje hustotu vzduchu, \u010d\u00edm\u017e se sni\u017euje \u00fa\u010dinnost chlazen\u00ed elektrick\u00e9ho za\u0159\u00edzen\u00ed. Odvod tepla z povrch\u016f kabel\u016f, transform\u00e1tor\u016f a jisti\u010d\u016f se st\u00e1v\u00e1 m\u00e9n\u011b \u00fa\u010dinn\u00fdm, co\u017e vy\u017eaduje sn\u00ed\u017een\u00ed kapacity.<\/p>\n<p><strong>Faktory korekce nadmo\u0159sk\u00e9 v\u00fd\u0161ky podle IEC 60364-5-52 a specifikac\u00ed v\u00fdrobce:<\/strong><\/p>\n<table style=\"border-collapse: collapse; width: 100%; margin-bottom: 20px;\" border=\"1\" cellpadding=\"8\">\n<thead>\n<tr style=\"background-color: #f2f2f2;\">\n<th>Nadmo\u0159sk\u00e1 v\u00fd\u0161ka (metry)<\/th>\n<th>Nadmo\u0159sk\u00e1 v\u00fd\u0161ka (stopy)<\/th>\n<th>Faktor sn\u00ed\u017een\u00ed jmenovit\u00e9ho v\u00fdkonu<\/th>\n<th>Faktor sn\u00ed\u017een\u00ed jmenovit\u00e9ho nap\u011bt\u00ed<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>0-1,000<\/td>\n<td>0-3,300<\/td>\n<td>1.00<\/td>\n<td>1.00<\/td>\n<\/tr>\n<tr>\n<td>1,000-1,500<\/td>\n<td>3,300-4,900<\/td>\n<td>0.99<\/td>\n<td>1.00<\/td>\n<\/tr>\n<tr>\n<td>1,500-2,000<\/td>\n<td>4,900-6,600<\/td>\n<td>0.97<\/td>\n<td>0.99<\/td>\n<\/tr>\n<tr>\n<td>2,000-3,000<\/td>\n<td>6,600-9,800<\/td>\n<td>0.94<\/td>\n<td>0.98<\/td>\n<\/tr>\n<tr>\n<td>3,000-4,000<\/td>\n<td>9,800-13,100<\/td>\n<td>0.90<\/td>\n<td>0.97<\/td>\n<\/tr>\n<tr>\n<td>4,000-5,000<\/td>\n<td>13,100-16,400<\/td>\n<td>0.86<\/td>\n<td>0.95<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3>Praktick\u00e9 d\u016fsledky pro horsk\u00e9 instalace<\/h3>\n<p><strong>P\u0159\u00edpadov\u00e1 studie:<\/strong> Nab\u00edjec\u00ed stanice pro elektromobily o v\u00fdkonu 22 kW instalovan\u00e1 v nadmo\u0159sk\u00e9 v\u00fd\u0161ce 2 500 metr\u016f v Coloradu vy\u017eaduje vodi\u010d dimenzovan\u00fd na <strong>120 A \u00f7 0,95 = 126,3 A<\/strong> po sn\u00ed\u017een\u00ed jmenovit\u00e9ho v\u00fdkonu v z\u00e1vislosti na nadmo\u0159sk\u00e9 v\u00fd\u0161ce. To p\u0159edstavuje sn\u00ed\u017een\u00ed kapacity o 5,3 % ve srovn\u00e1n\u00ed s instalacemi v nadmo\u0159sk\u00e9 v\u00fd\u0161ce hladiny mo\u0159e.<\/p>\n<p><strong>\u00davahy o vybaven\u00ed:<\/strong><\/p>\n<ul>\n<li>Jisti\u010de mohou m\u00edt sn\u00ed\u017eenou vyp\u00ednac\u00ed schopnost v nadmo\u0159sk\u00e9 v\u00fd\u0161ce<\/li>\n<li>\u00da\u010dinnost chlazen\u00ed transform\u00e1toru kles\u00e1 p\u0159ibli\u017en\u011b o <strong>1 % na 100 metr\u016f<\/strong> nad 1 000 m<\/li>\n<li>Rozvad\u011b\u010de a panelov\u00e9 desky vy\u017eaduj\u00ed v\u011bt\u0161\u00ed sk\u0159\u00edn\u011b pro dostate\u010dn\u00e9 konvek\u010dn\u00ed chlazen\u00ed<\/li>\n<li>Pr\u016fmyslov\u00e9 VIOX <a href=\"https:\/\/test.viox.com\/cs\/circuit-breaker-altitude-derating-guide\/\">jisti\u010de<\/a> zahrnuj\u00ed jmenovit\u00e9 hodnoty kompenzace nadmo\u0159sk\u00e9 v\u00fd\u0161ky a\u017e do 4 000 m<\/li>\n<\/ul>\n<p><strong>Pozn\u00e1mka:<\/strong> Za\u0159\u00edzen\u00ed chlazen\u00e9 kapalinou m\u016f\u017ee \u010d\u00e1ste\u010dn\u011b kompenzovat vliv nadmo\u0159sk\u00e9 v\u00fd\u0161ky sn\u00ed\u017een\u00edm teploty chladic\u00ed kapaliny, ale syst\u00e9my chlazen\u00e9 vzduchem vy\u017eaduj\u00ed striktn\u00ed dodr\u017eov\u00e1n\u00ed tabulek sn\u00ed\u017een\u00ed v\u00fdkonu.<\/p>\n<figure style=\"text-align: center; margin: 20px 0;\"><img decoding=\"async\" style=\"max-width: 100%; height: auto;\" src=\"https:\/\/img.viox.com\/Altitude-derating-factors-illustrated-through-atmospheric-pressure-reduction-and-its-impact-on-electrical-equipment-cooling-efficiency.webp\" alt=\"Altitude derating factors illustrated through atmospheric pressure reduction and its impact on electrical equipment cooling efficiency\" \/><figcaption style=\"font-style: italic; color: #555; margin-top: 8px;\">Faktory sn\u00ed\u017een\u00ed v\u00fdkonu v z\u00e1vislosti na nadmo\u0159sk\u00e9 v\u00fd\u0161ce ilustrovan\u00e9 prost\u0159ednictv\u00edm sn\u00ed\u017een\u00ed atmosf\u00e9rick\u00e9ho tlaku a jeho dopadu na \u00fa\u010dinnost chlazen\u00ed elektrick\u00fdch za\u0159\u00edzen\u00ed.<\/figcaption><\/figure>\n<h2>Odd\u00edl 3: Seskupov\u00e1n\u00ed kabel\u016f a sn\u00ed\u017een\u00ed v\u00fdkonu svazkov\u00e1n\u00edm<\/h2>\n<h3>Vz\u00e1jemn\u00e9 tepeln\u00e9 \u00fa\u010dinky v instalac\u00edch s v\u00edce kabely<\/h3>\n<p>Pokud v\u00edce vodi\u010d\u016f vedouc\u00edch proud sd\u00edl\u00ed stejnou kabelovou trasu, kabelov\u00fd \u017elab nebo podzemn\u00ed v\u00fdkop, generuj\u00ed <strong>vz\u00e1jemn\u00e9 zah\u0159\u00edv\u00e1n\u00ed<\/strong> kter\u00e9 zhor\u0161uje schopnost ka\u017ed\u00e9ho kabelu odv\u00e1d\u011bt teplo. Tento jev vy\u017eaduje agresivn\u00ed sn\u00ed\u017een\u00ed v\u00fdkonu podle NEC Tabulky 310.15(C)(1) a IEC 60364-5-52.<\/p>\n<p><strong>Faktory sn\u00ed\u017een\u00ed v\u00fdkonu seskupov\u00e1n\u00edm (normy NEC\/IEC):<\/strong><\/p>\n<table style=\"border-collapse: collapse; width: 100%; margin-bottom: 20px;\" border=\"1\" cellpadding=\"8\">\n<thead>\n<tr style=\"background-color: #f2f2f2;\">\n<th>Po\u010det vodi\u010d\u016f vedouc\u00edch proud<\/th>\n<th>Korek\u010dn\u00ed faktor<\/th>\n<th>Efektivn\u00ed ztr\u00e1ta proudov\u00e9 zat\u00ed\u017eitelnosti<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>1-3<\/td>\n<td>1.00<\/td>\n<td>0%<\/td>\n<\/tr>\n<tr>\n<td>4-6<\/td>\n<td>0.80<\/td>\n<td>20%<\/td>\n<\/tr>\n<tr>\n<td>7-9<\/td>\n<td>0.70<\/td>\n<td>30%<\/td>\n<\/tr>\n<tr>\n<td>10-20<\/td>\n<td>0.50<\/td>\n<td>50%<\/td>\n<\/tr>\n<tr>\n<td>21-30<\/td>\n<td>0.45<\/td>\n<td>55%<\/td>\n<\/tr>\n<tr>\n<td>31-40<\/td>\n<td>0.40<\/td>\n<td>60%<\/td>\n<\/tr>\n<tr>\n<td>41+<\/td>\n<td>0.35<\/td>\n<td>65%<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><strong>Kritick\u00e9 aspekty:<\/strong><\/p>\n<ul>\n<li><strong>Neutr\u00e1ln\u00ed vodi\u010de vedouc\u00ed harmonick\u00e9 proudy se po\u010d\u00edtaj\u00ed jako vodi\u010de vedouc\u00ed proud<\/strong><\/li>\n<li>Uzem\u0148ovac\u00ed\/pospojovac\u00ed vodi\u010de se nezapo\u010d\u00edt\u00e1vaj\u00ed do sn\u00ed\u017een\u00ed v\u00fdkonu seskupov\u00e1n\u00edm<\/li>\n<li>Kabely pracuj\u00edc\u00ed na &lt;35% jmenovit\u00e9 hodnoty seskupen\u00ed mohou b\u00fdt z po\u010dtu vylou\u010deny<\/li>\n<li>Kr\u00e1tk\u00e9 d\u00e9lky seskupen\u00ed (&lt;3 m pro vodi\u010de \u2265150 mm\u00b2) mohou b\u00fdt osvobozeny od sn\u00ed\u017een\u00ed v\u00fdkonu<\/li>\n<\/ul>\n<h3>Vliv zp\u016fsobu instalace<\/h3>\n<p><strong>Instalace kabelov\u00fdch \u017elab\u016f<\/strong> (Zp\u016fsob instalace NEC 12\/13):<\/p>\n<ul>\n<li><strong>Jedna vrstva, s mezerami:<\/strong> Pou\u017eijte faktor seskupen\u00ed pro skute\u010dn\u00fd po\u010det obvod\u016f<\/li>\n<li><strong>V\u00edce vrstev, dot\u00fdkaj\u00edc\u00ed se:<\/strong> Pou\u017eijte faktor 0,70 pro 2 vrstvy, 0,60 pro 3+ vrstvy<\/li>\n<li><strong>Zakryt\u00e9 \u017elaby s omezen\u00fdm v\u011btr\u00e1n\u00edm:<\/strong> Dal\u0161\u00ed reduk\u010dn\u00ed faktor 0,95<\/li>\n<\/ul>\n<p><strong>Podzemn\u00ed instalace kabelov\u00fdch kan\u00e1l\u016f:<\/strong><\/p>\n<ul>\n<li><strong>Trojl\u00edstkov\u00e1 formace (3 f\u00e1ze se dot\u00fdkaj\u00ed):<\/strong> Faktor 0,80 pro jeden obvod, 0,70 pro v\u00edce obvod\u016f<\/li>\n<li><strong>Ploch\u00e1 formace s rozestupem 2\u00d7 pr\u016fm\u011br:<\/strong> Faktor 0,85<\/li>\n<li><strong>V\u00edce chr\u00e1ni\u010dek ve stejn\u00e9m v\u00fdkopu:<\/strong> Faktory 0,70-0,60 v z\u00e1vislosti na konfiguraci<\/li>\n<\/ul>\n<p>Pro <a href=\"https:\/\/test.viox.com\/cs\/100a-panel-ev-charger-upgrade\/\">Dimenzov\u00e1n\u00ed kabel\u016f pro nab\u00edjen\u00ed EV<\/a>, sn\u00ed\u017een\u00ed v\u00fdkonu seskupov\u00e1n\u00edm je obzvl\u00e1\u0161t\u011b kritick\u00e9 v instalac\u00edch parkovac\u00edch gar\u00e1\u017e\u00ed, kde v\u00edce nab\u00edje\u010dek 7 kW nebo 22 kW sd\u00edl\u00ed spole\u010dn\u00e9 kabelov\u00e9 trasy.<\/p>\n<figure style=\"text-align: center; margin: 20px 0;\"><img decoding=\"async\" style=\"max-width: 100%; height: auto;\" src=\"https:\/\/img.viox.com\/Multiple-power-cables-grouped-in-cable-tray-installation-requiring-ampacity-adjustment-factors-to-prevent-overheating-in-VIOX-electrical-distribution-system.webp\" alt=\"Multiple power cables grouped in cable tray installation requiring ampacity adjustment factors to prevent overheating in VIOX electrical distribution system\" \/><figcaption style=\"font-style: italic; color: #555; margin-top: 8px;\">V\u00edce nap\u00e1jec\u00edch kabel\u016f seskupen\u00fdch v instalaci kabelov\u00e9ho \u017elabu vy\u017eaduje korek\u010dn\u00ed faktory proudov\u00e9 zat\u00ed\u017eitelnosti, aby se zabr\u00e1nilo p\u0159eh\u0159\u00e1t\u00ed v elektrick\u00e9m rozvodn\u00e9m syst\u00e9mu VIOX.<\/figcaption><\/figure>\n<h2>Odd\u00edl 4: V\u00fdpo\u010det kombinovan\u00fdch faktor\u016f sn\u00ed\u017een\u00ed v\u00fdkonu<\/h2>\n<h3>Metodika n\u00e1soben\u00ed<\/h3>\n<p>Pokud existuje sou\u010dasn\u011b v\u00edce podm\u00ednek pro sn\u00ed\u017een\u00ed v\u00fdkonu, faktory se <strong>n\u00e1sob\u00ed dohromady<\/strong> pro ur\u010den\u00ed kone\u010dn\u00e9 upraven\u00e9 proudov\u00e9 zat\u00ed\u017eitelnosti:<\/p>\n<p><strong>Hlavn\u00ed vzorec:<\/strong><\/p>\n<pre style=\"background: #f4f4f4; padding: 10px; border-radius: 4px; overflow-x: auto;\">Upraven\u00e1 proudov\u00e1 zat\u00ed\u017eitelnost = Z\u00e1kladn\u00ed proudov\u00e1 zat\u00ed\u017eitelnost \u00d7 Teplotn\u00ed faktor \u00d7 Faktor nadmo\u0159sk\u00e9 v\u00fd\u0161ky \u00d7 Faktor seskupen\u00ed \u00d7 Faktor instalace<\/pre>\n<p><strong>Proces v\u00fdpo\u010dtu krok za krokem:<\/strong><\/p>\n<ol>\n<li><strong>Identifikujte z\u00e1kladn\u00ed proudovou zat\u00ed\u017eitelnost<\/strong> z NEC Tabulky 310.16 nebo tabulek vodi\u010d\u016f IEC (pou\u017eijte sloupec 75 \u00b0C nebo 90 \u00b0C na z\u00e1klad\u011b jmenovit\u00fdch hodnot svorek podle NEC 110.14(C))<\/li>\n<li><strong>Ur\u010dete v\u0161echny pou\u017eiteln\u00e9 faktory sn\u00ed\u017een\u00ed v\u00fdkonu<\/strong> pro va\u0161i konkr\u00e9tn\u00ed instalaci<\/li>\n<li><strong>Vyn\u00e1sobte faktory dohromady<\/strong> abyste z\u00edskali kumulativn\u00ed sn\u00ed\u017een\u00ed<\/li>\n<li><strong>Vypo\u010d\u00edtejte upravenou proudovou zat\u00ed\u017eitelnost<\/strong> a porovnejte s po\u017eadavky na zat\u00ed\u017een\u00ed<\/li>\n<li><strong>Pokud je upraven\u00e1 proudov\u00e1 zat\u00ed\u017eitelnost &lt; po\u017eadovan\u00e1 proudov\u00e1 zat\u00ed\u017eitelnost, zv\u011bt\u0161ete pr\u016f\u0159ez vodi\u010de a p\u0159epo\u010dt\u011bte<\/strong><\/li>\n<\/ol>\n<h3>P\u0159\u00edklad z re\u00e1ln\u00e9ho sv\u011bta: DC slu\u010dova\u010d sol\u00e1rn\u00edho pole<\/h3>\n<p><strong>Sc\u00e9n\u00e1\u0159:<\/strong> 8 sol\u00e1rn\u00edch string\u016f nap\u00e1jej\u00edc\u00edch st\u0159e\u0161n\u00ed slu\u010dovac\u00ed box v letn\u00edch podm\u00ednk\u00e1ch v Arizon\u011b<\/p>\n<p><strong>Zadan\u00e9 parametry:<\/strong><\/p>\n<ul>\n<li>Proud z\u00e1t\u011b\u017ee: 64 A (8 string\u016f \u00d7 8 A ka\u017ed\u00fd)<\/li>\n<li>Z\u00e1kladn\u00ed vodi\u010d: 4 AWG m\u011bd\u011bn\u00fd THHN (85 A @ 75 \u00b0C, 95 A @ 90 \u00b0C)<\/li>\n<li>Teplota okol\u00ed: 50 \u00b0C (vystaven\u00ed st\u0159e\u0161e)<\/li>\n<li>Nadmo\u0159sk\u00e1 v\u00fd\u0161ka: 1 100 metr\u016f<\/li>\n<li>Po\u010det vodi\u010d\u016f vedouc\u00edch proud: 16 (8 kladn\u00fdch + 8 z\u00e1porn\u00fdch)<\/li>\n<li>Instalace: Kabelov\u00fd \u017elab, jedna vrstva<\/li>\n<\/ul>\n<p><strong>Calculation:<\/strong><\/p>\n<pre style=\"background: #f4f4f4; padding: 10px; border-radius: 4px; overflow-x: auto;\">Z\u00e1kladn\u00ed proudov\u00e1 zat\u00ed\u017eitelnost (90 \u00b0C): 95 A\n<\/pre>\n<p><strong>V\u00fdsledek:<\/strong> 4 AWG je <strong>nedostate\u010dn\u00fd<\/strong> (38,7 A &lt; po\u017eadovan\u00fdch 64 A). Zkuste 1\/0 AWG (z\u00e1klad 150 A):<\/p>\n<pre style=\"background: #f4f4f4; padding: 10px; border-radius: 4px; overflow-x: auto;\">Upraven\u00e1 proudov\u00e1 zat\u00ed\u017eitelnost = 150 A \u00d7 0,82 \u00d7 0,99 \u00d7 0,50 = 60,8 A<\/pre>\n<p><strong>St\u00e1le nedostate\u010dn\u00e9.<\/strong> Kone\u010dn\u00e9 \u0159e\u0161en\u00ed: <strong>2\/0 AWG<\/strong> (Z\u00e1klad 175 A):<\/p>\n<pre style=\"background: #f4f4f4; padding: 10px; border-radius: 4px; overflow-x: auto;\">Upraven\u00e1 proudov\u00e1 zat\u00ed\u017eitelnost = 175 A \u00d7 0,82 \u00d7 0,99 \u00d7 0,50 = 70,9 A \u2713<\/pre>\n<p>Tento p\u0159\u00edklad ukazuje, pro\u010d jsou poddimenzovan\u00e9 vodi\u010de b\u011b\u017en\u00e9 u sol\u00e1rn\u00edch instalac\u00ed \u2013 reduk\u010dn\u00ed faktory mohou sn\u00ed\u017eit proudovou zat\u00ed\u017eitelnost o <strong>60 % nebo v\u00edce<\/strong> v n\u00e1ro\u010dn\u00fdch podm\u00ednk\u00e1ch.<\/p>\n<h3>P\u0159\u00edklad komer\u010dn\u00ed nab\u00edjec\u00ed stanice pro elektromobily<\/h3>\n<p><strong>Sc\u00e9n\u00e1\u0159:<\/strong> Podzemn\u00ed p\u0159\u00edvod k baterii nab\u00edje\u010dek pro elektromobily \u00farovn\u011b 2 s v\u00fdkonem 22 kW<\/p>\n<p><strong>Zadan\u00e9 parametry:<\/strong><\/p>\n<ul>\n<li>Proudov\u00e9 zat\u00ed\u017een\u00ed: 96 A (t\u0159i 32A nab\u00edje\u010dky)<\/li>\n<li>Vodi\u010d: m\u011bd\u011bn\u00fd kabel 3 AWG XHHW-2 (115 A p\u0159i 75 \u00b0C, 130 A p\u0159i 90 \u00b0C)<\/li>\n<li>Teplota p\u016fdy: 30 \u00b0C<\/li>\n<li>Hloubka ulo\u017een\u00ed: 0,8 m<\/li>\n<li>Po\u010det obvod\u016f v r\u00fdze: 1 (3 vodi\u010de + zem)<\/li>\n<li>Faktor trval\u00e9ho zat\u00ed\u017een\u00ed: 1,25 (NEC 625.41 vy\u017eaduje dimenzov\u00e1n\u00ed 125 % pro za\u0159\u00edzen\u00ed pro elektromobily)<\/li>\n<\/ul>\n<p><strong>Calculation:<\/strong><\/p>\n<pre style=\"background: #f4f4f4; padding: 10px; border-radius: 4px; overflow-x: auto;\">Z\u00e1kladn\u00ed proudov\u00e1 zat\u00ed\u017eitelnost (90 \u00b0C): 130 A\n<\/pre>\n<p><strong>V\u00fdsledek:<\/strong> 3 AWG je <strong>nedostate\u010dn\u00fd<\/strong> (114,8 A &lt; 120 A). \u0158e\u0161en\u00ed: <strong>2 AWG<\/strong> (Z\u00e1klad 150 A):<\/p>\n<pre style=\"background: #f4f4f4; padding: 10px; border-radius: 4px; overflow-x: auto;\">Upraven\u00e1 proudov\u00e1 zat\u00ed\u017eitelnost = 150 A \u00d7 0,92 \u00d7 0,96 = 132,5 A \u2713<\/pre>\n<p>Porozum\u011bn\u00ed <a href=\"https:\/\/test.viox.com\/cs\/cable-size-types-mm-awg-bs-conversion-guide\/\">spr\u00e1vn\u00e9 dimenzov\u00e1n\u00ed jisti\u010de pro nab\u00edje\u010dky elektromobil\u016f<\/a> vy\u017eaduje koordinaci proudov\u00e9 zat\u00ed\u017eitelnosti vodi\u010de s jmenovit\u00fdmi hodnotami nadproudov\u00e9 ochrany po aplikaci v\u0161ech reduk\u010dn\u00edch faktor\u016f.<\/p>\n<figure style=\"text-align: center; margin: 20px 0;\"><img decoding=\"async\" style=\"max-width: 100%; height: auto;\" src=\"https:\/\/img.viox.com\/Cable-sizing-calculation-flowchart-showing-systematic-application-of-temperature-altitude-and-grouping-derating-factors-per-NEC-and-IEC-standards.webp\" alt=\"Cable sizing calculation flowchart showing systematic application of temperature, altitude, and grouping derating factors per NEC and IEC standards\" \/><figcaption style=\"font-style: italic; color: #555; margin-top: 8px;\">V\u00fdvojov\u00fd diagram v\u00fdpo\u010dtu dimenzov\u00e1n\u00ed kabel\u016f zn\u00e1zor\u0148uj\u00edc\u00ed systematickou aplikaci teplotn\u00edch, nadmo\u0159sk\u00fdch a skupinov\u00fdch reduk\u010dn\u00edch faktor\u016f podle norem NEC a IEC.<\/figcaption><\/figure>\n<h2>Rychl\u00e9 referen\u010dn\u00ed tabulky reduk\u010dn\u00edch faktor\u016f<\/h2>\n<h3>Kombinovan\u00e1 redukce teploty a seskupen\u00ed<\/h3>\n<table style=\"border-collapse: collapse; width: 100%; margin-bottom: 20px;\" border=\"1\" cellpadding=\"8\">\n<thead>\n<tr style=\"background-color: #f2f2f2;\">\n<th>Sc\u00e9n\u00e1\u0159<\/th>\n<th>Teplotn\u00ed faktor<\/th>\n<th>Faktor seskupen\u00ed<\/th>\n<th>Kombinovan\u00fd<\/th>\n<th>P\u0159\u00edklad: Z\u00e1klad 100 A \u2192 Kone\u010dn\u00e1 proudov\u00e1 zat\u00ed\u017eitelnost<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>3 kabely, 30 \u00b0C<\/td>\n<td>1.00<\/td>\n<td>1.00<\/td>\n<td>1.00<\/td>\n<td>100A<\/td>\n<\/tr>\n<tr>\n<td>6 kabel\u016f, 40 \u00b0C<\/td>\n<td>0.91<\/td>\n<td>0.80<\/td>\n<td>0.73<\/td>\n<td>73 A<\/td>\n<\/tr>\n<tr>\n<td>9 kabel\u016f, 50 \u00b0C<\/td>\n<td>0.82<\/td>\n<td>0.70<\/td>\n<td>0.57<\/td>\n<td>57A<\/td>\n<\/tr>\n<tr>\n<td>15 kabel\u016f, 50 \u00b0C + nadmo\u0159sk\u00e1 v\u00fd\u0161ka 2000 m<\/td>\n<td>0.82<\/td>\n<td>0.50<\/td>\n<td>0.39*<\/td>\n<td>39A<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><em>*Zahrnuje faktor nadmo\u0159sk\u00e9 v\u00fd\u0161ky 0,94 (0,82 \u00d7 0,50 \u00d7 0,94 = 0,385)<\/em><\/p>\n<h3>Srovn\u00e1n\u00ed z\u00e1kladn\u00edch jmenovit\u00fdch hodnot zp\u016fsobu instalace<\/h3>\n<table style=\"border-collapse: collapse; width: 100%; margin-bottom: 20px;\" border=\"1\" cellpadding=\"8\">\n<thead>\n<tr style=\"background-color: #f2f2f2;\">\n<th>Zp\u016fsob instalace<\/th>\n<th>Relativn\u00ed proudov\u00e1 zat\u00ed\u017eitelnost<\/th>\n<th>Typick\u00e9 aplikace<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Jeden kabel ve voln\u00e9m vzduchu<\/td>\n<td>1,00 (nejvy\u0161\u0161\u00ed)<\/td>\n<td>Nadzemn\u00ed rozp\u011bt\u00ed, testovac\u00ed sestavy<\/td>\n<\/tr>\n<tr>\n<td>P\u0159ipevn\u011bno p\u0159\u00edmo na povrch<\/td>\n<td>0.95<\/td>\n<td>Pr\u016fmyslov\u00e9 st\u011bny, konstruk\u010dn\u00ed mont\u00e1\u017e<\/td>\n<\/tr>\n<tr>\n<td>V trubce\/kan\u00e1lu (1-3 kabely)<\/td>\n<td>0.80<\/td>\n<td>Elektroinstalace budov, chr\u00e1n\u011bn\u00e9 trasy<\/td>\n<\/tr>\n<tr>\n<td>Kabelov\u00fd \u017eeb\u0159\u00edk, jedna vrstva<\/td>\n<td>0.75<\/td>\n<td>Technick\u00e9 m\u00edstnosti, datov\u00e1 centra<\/td>\n<\/tr>\n<tr>\n<td>Ulo\u017eeno p\u0159\u00edmo v zemi<\/td>\n<td>0.70<\/td>\n<td>Podzemn\u00ed rozvod<\/td>\n<\/tr>\n<tr>\n<td>V podzemn\u00edm kan\u00e1lu<\/td>\n<td>0.65<\/td>\n<td>D\u00e1lkov\u00fd p\u0159enos<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>\u010casto Kladen\u00e9 Ot\u00e1zky<\/h2>\n<p><strong>Ot\u00e1zka 1: Mus\u00edm pou\u017e\u00edt reduk\u010dn\u00ed faktory, pokud m\u016fj kabel pracuje pod svou jmenovitou kapacitou?<\/strong><\/p>\n<p>Ano, reduk\u010dn\u00ed faktory jsou povinn\u00e9 bez ohledu na procentu\u00e1ln\u00ed zat\u00ed\u017een\u00ed. Upravuj\u00ed maxim\u00e1ln\u00ed bezpe\u010dnou proudovou zat\u00ed\u017eitelnost vodi\u010de na z\u00e1klad\u011b podm\u00ednek prost\u0159ed\u00ed. Jedinou v\u00fdjimkou jsou kabely provozovan\u00e9 s m\u00e9n\u011b ne\u017e 35 % jejich sdru\u017een\u00e9ho jmenovit\u00e9ho proudu na kr\u00e1tk\u00e9 vzd\u00e1lenosti (&lt;3 m), kter\u00e9 mohou b\u00fdt vyjmuty z po\u010dtu sdru\u017een\u00ed podle IEC 60364-5-52.<\/p>\n<p><strong>Ot\u00e1zka 2: Mohu pou\u017e\u00edt sloupec proudov\u00e9 zat\u00ed\u017eitelnosti 90 \u00b0C pro vodi\u010d THHN, pokud je zakon\u010den na jisti\u010di s jmenovitou hodnotou 75 \u00b0C?<\/strong><\/p>\n<p>Ne pro kone\u010dn\u00e9 rozhodnut\u00ed o dimenzov\u00e1n\u00ed. NEC 110.14(C) vy\u017eaduje pou\u017eit\u00ed ni\u017e\u0161\u00ed jmenovit\u00e9 teploty svorek (75 \u00b0C) pro obvody \u2264100 A, pokud za\u0159\u00edzen\u00ed nen\u00ed specificky uvedeno pro 90 \u00b0C. Nicm\u00e9n\u011b, vy <strong>m\u011blo<\/strong> pou\u017eijte z\u00e1kladn\u00ed proudovou zat\u00ed\u017eitelnost 90 \u00b0C p\u0159i aplikaci reduk\u010dn\u00edch faktor\u016f a pot\u00e9 ov\u011b\u0159te, zda redukovan\u00fd v\u00fdsledek nep\u0159ekra\u010duje jmenovitou hodnotu 75 \u00b0C. Tento p\u0159\u00edstup maximalizuje kapacitu vodi\u010de a z\u00e1rove\u0148 zaji\u0161\u0165uje bezpe\u010dn\u00e9 zakon\u010den\u00ed.<\/p>\n<p><strong>Ot\u00e1zka 3: Jak m\u00e1m \u0159e\u0161it sm\u00ed\u0161en\u00e9 reduk\u010dn\u00ed podm\u00ednky, nap\u0159\u00edklad kabely, kter\u00e9 jsou \u010d\u00e1ste\u010dn\u011b ulo\u017eeny v zemi a \u010d\u00e1ste\u010dn\u011b ve vzduchu?<\/strong><\/p>\n<p>Pou\u017eijte <strong>nejv\u00edce omezuj\u00edc\u00ed<\/strong> reduk\u010dn\u00ed faktor pro instala\u010dn\u00ed segment, kter\u00fd p\u0159edstavuje tepeln\u00e9 \u00fazk\u00e9 m\u00edsto. Nap\u0159\u00edklad, pokud je 80 % trasy kabelu ve voln\u00e9m vzduchu, ale 20 % proch\u00e1z\u00ed tepelnou izolac\u00ed, mus\u00ed b\u00fdt cel\u00fd obvod redukov\u00e1n pro izolovanou \u010d\u00e1st. Konzervativn\u00ed in\u017een\u00fdrsk\u00e1 praxe je v\u017edy pou\u017e\u00edvat nejhor\u0161\u00ed mo\u017en\u00e9 podm\u00ednky pro celou d\u00e9lku obvodu.<\/p>\n<p><strong>Ot\u00e1zka 4: Existuj\u00ed v\u00fdjimky pro kr\u00e1tk\u00e9 trasy kabel\u016f, kter\u00e9 nevy\u017eaduj\u00ed plnou redukci?<\/strong><\/p>\n<p>Ano. NEC umo\u017e\u0148uje v\u00fdjimky pro <strong>kr\u00e1tk\u00e9 trubky<\/strong> (kr\u00e1tk\u00e9 \u00faseky trubek \u2264600 mm) obsahuj\u00edc\u00ed libovoln\u00fd po\u010det vodi\u010d\u016f. IEC 60364-5-52 umo\u017e\u0148uje ignorovat redukci seskupen\u00ed pro d\u00e9lky kabel\u016f pod 1 m pro vodi\u010de &lt;150 mm\u00b2 nebo 3 m pro vodi\u010de \u2265150 mm\u00b2. Nicm\u00e9n\u011b, teplotn\u00ed a nadmo\u0159sk\u00e1 redukce se v\u017edy pou\u017eij\u00ed bez ohledu na d\u00e9lku kabelu.<\/p>\n<p><strong>Ot\u00e1zka 5: Jak\u00e9 reduk\u010dn\u00ed faktory se vztahuj\u00ed na kabely s miner\u00e1ln\u00ed izolac\u00ed (MI)?<\/strong><\/p>\n<p>Kabely MI (konstrukce MIMS) maj\u00ed vynikaj\u00edc\u00ed tepeln\u00e9 vlastnosti a \u010dasto vy\u017eaduj\u00ed <strong>\u017e\u00e1dnou redukci<\/strong> pro seskupov\u00e1n\u00ed, pokud nejsou v kontaktu s jin\u00fdmi typy kabel\u016f. Nicm\u00e9n\u011b, teplotn\u00ed a nadmo\u0159sk\u00e1 v\u00fd\u0161ka st\u00e1le plat\u00ed. Pro konkr\u00e9tn\u00ed pokyny ohledn\u011b vodi\u010d\u016f s miner\u00e1ln\u00ed izolac\u00ed se obra\u0165te na specifikace v\u00fdrobce a AS\/NZS 3008.1 nebo IEC 60702.<\/p>\n<p><strong>Q6: Jak harmonick\u00e9 ovliv\u0148uj\u00ed po\u017eadavky na sn\u00ed\u017een\u00ed jmenovit\u00e9ho proudu?<\/strong><\/p>\n<p><strong>T\u0159et\u00ed harmonick\u00e9 proudy<\/strong> v neutr\u00e1ln\u00edch vodi\u010d\u00edch vytv\u00e1\u0159ej\u00ed dodate\u010dn\u00e9 ztr\u00e1ty I\u00b2R, co\u017e vy\u017eaduje, aby byl neutr\u00e1l po\u010d\u00edt\u00e1n jako vodi\u010d vedouc\u00ed proud pro \u00fa\u010dely sn\u00ed\u017een\u00ed jmenovit\u00e9ho proudu p\u0159i seskupov\u00e1n\u00ed. V instalac\u00edch s v\u00fdznamn\u00fdm neline\u00e1rn\u00edm zat\u00ed\u017een\u00edm (VFD, LED drivery, elektronick\u00e9 p\u0159ed\u0159adn\u00edky) m\u016f\u017ee obsah harmonick\u00e9ho proudu vy\u017eadovat dimenzov\u00e1n\u00ed neutr\u00e1ln\u00edch vodi\u010d\u016f na 200 % vodi\u010d\u016f f\u00e1zov\u00fdch a odpov\u00eddaj\u00edc\u00ed \u00fapravy sn\u00ed\u017een\u00ed jmenovit\u00e9ho proudu.<\/p>\n<p><strong>Q7: Mohu kompenzovat vysokou okoln\u00ed teplotu p\u0159edimenzov\u00e1n\u00edm vodi\u010de nam\u00edsto pou\u017eit\u00ed reduk\u010dn\u00edch faktor\u016f?<\/strong><\/p>\n<p>Ne. Mus\u00edte <strong>v\u017edy pou\u017e\u00edt p\u0159\u00edslu\u0161n\u00e9 reduk\u010dn\u00ed faktory<\/strong> pro ur\u010den\u00ed upraven\u00e9 proudov\u00e9 zat\u00ed\u017eitelnosti vodi\u010de a pot\u00e9 vybrat velikost vodi\u010de, kde upraven\u00e1 proudov\u00e1 zat\u00ed\u017eitelnost spl\u0148uje nebo p\u0159ekra\u010duje po\u017eadavky na zat\u00ed\u017een\u00ed. Pouh\u00e9 p\u0159edimenzov\u00e1n\u00ed bez \u0159\u00e1dn\u00e9ho v\u00fdpo\u010dtu poru\u0161uje metodiku NEC a m\u016f\u017ee st\u00e1le v\u00e9st k poddimenzovan\u00fdm vodi\u010d\u016fm. Reduk\u010dn\u00ed faktory zohled\u0148uj\u00ed fyzik\u00e1ln\u00ed tepeln\u00e1 omezen\u00ed, kter\u00e1 nelze ignorovat.<\/p>\n<h2>Z\u00e1v\u011br: In\u017een\u00fdrsk\u00e1 excelence prost\u0159ednictv\u00edm spr\u00e1vn\u00e9ho sn\u00ed\u017een\u00ed jmenovit\u00e9ho proudu<\/h2>\n<p>P\u0159esn\u00e9 v\u00fdpo\u010dty sn\u00ed\u017een\u00ed jmenovit\u00e9ho proudu jsou pro elektrickou bezpe\u010dnost, soulad s p\u0159edpisy a \u017eivotnost syst\u00e9mu nezbytn\u00e9. P\u0159\u00edklady v t\u00e9to p\u0159\u00edru\u010dce ukazuj\u00ed, \u017ee re\u00e1ln\u00e9 instalace b\u011b\u017en\u011b \u010del\u00ed sn\u00ed\u017een\u00ed proudov\u00e9 zat\u00ed\u017eitelnosti o 40\u201360 % ve srovn\u00e1n\u00ed se standardn\u00edmi tabulkov\u00fdmi hodnotami \u2013 co\u017e je realita, kter\u00e1 vy\u017eaduje d\u016fkladnou in\u017een\u00fdrskou anal\u00fdzu.<\/p>\n<p><strong>Osv\u011bd\u010den\u00e9 postupy pro profesion\u00e1ln\u00ed instalace:<\/strong><\/p>\n<ul>\n<li><strong>V\u017edy pou\u017e\u00edvejte nejvy\u0161\u0161\u00ed teplotn\u00ed hodnocen\u00ed vodi\u010de<\/strong> (90 \u00b0C) jako v\u00fdchoz\u00ed bod pro v\u00fdpo\u010dty sn\u00ed\u017een\u00ed jmenovit\u00e9ho proudu<\/li>\n<li><strong>Ov\u011b\u0159te teplotn\u00ed hodnocen\u00ed svorek<\/strong> a upravte kone\u010dn\u00fd v\u00fdb\u011br podle NEC 110.14(C)<\/li>\n<li><strong>Dokumentujte v\u0161echny reduk\u010dn\u00ed faktory<\/strong> pou\u017eit\u00e9 ve va\u0161ich v\u00fdpo\u010dtech pro kontrolu souladu<\/li>\n<li><strong>Zva\u017ete budouc\u00ed zat\u00ed\u017een\u00ed<\/strong> a pou\u017eijte faktory trval\u00e9ho zat\u00ed\u017een\u00ed 125 %, kde je to relevantn\u00ed<\/li>\n<li><strong>Specifikujte kvalitn\u00ed ochranu obvod\u016f<\/strong> od v\u00fdrobc\u016f, jako je VIOX, kte\u0159\u00ed poskytuj\u00ed hodnocen\u00ed kompenzovan\u00e9 nadmo\u0159skou v\u00fd\u0161kou a termomagnetickou p\u0159esnost<\/li>\n<\/ul>\n<p>Komplexn\u00ed \u0159ada spole\u010dnosti VIOX Electric <a href=\"https:\/\/test.viox.com\/cs\/what-is-a-molded-case-circuit-breaker-mccb\/\">pr\u016fmyslov\u00fdch jisti\u010d\u016f a ochrann\u00fdch za\u0159\u00edzen\u00ed<\/a> jsou navr\u017eeny se syst\u00e9my \u0159\u00edzen\u00ed teploty, kter\u00e9 udr\u017euj\u00ed v\u00fdkon v teplotn\u00edch rozsaz\u00edch od -40 \u00b0C do +70 \u00b0C a v nadmo\u0159sk\u00fdch v\u00fd\u0161k\u00e1ch a\u017e 4 000 metr\u016f. N\u00e1\u0161 t\u00fdm technick\u00e9 podpory poskytuje aplika\u010dn\u011b specifick\u00e9 pokyny pro sn\u00ed\u017een\u00ed jmenovit\u00e9ho proudu pro sol\u00e1rn\u00ed, EV nab\u00edjen\u00ed a pr\u016fmyslov\u00e9 instalace po cel\u00e9m sv\u011bt\u011b.<\/p>\n<p><strong>Kdy\u017e z\u00e1le\u017e\u00ed na p\u0159esnosti specifikace, spr\u00e1vn\u00e9 sn\u00ed\u017een\u00ed jmenovit\u00e9ho proudu nen\u00ed v\u00fdpo\u010det \u2013 je to z\u00e1vazek k bezpe\u010dnosti.<\/strong> Pro technickou konzultaci k va\u0161emu dal\u0161\u00edmu projektu kontaktujte in\u017een\u00fdrsk\u00fd t\u00fdm VIOX Electric nebo prozkoumejte na\u0161e <a href=\"https:\/\/test.viox.com\/cs\/types-of-circuit-breakers\/\">kompletn\u00ed \u0159e\u0161en\u00ed ochrany obvod\u016f<\/a>.<\/p>\n<hr \/>\n<p><strong>Souvisej\u00edc\u00ed technick\u00e9 zdroje:<\/strong><\/p>\n<ul>\n<li><a href=\"https:\/\/test.viox.com\/cs\/how-to-know-if-circuit-breaker-is-bad\/\">Jak poznat, zda je jisti\u010d \u0161patn\u00fd<\/a><\/li>\n<li><a href=\"https:\/\/test.viox.com\/cs\/rccb-ev-charging-type-b-vs-type-f-vs-type-ev\/\">Ochrana nab\u00edjen\u00ed EV: Pr\u016fvodce souladem s NEC\/IEC<\/a><\/li>\n<li><a href=\"https:\/\/test.viox.com\/cs\/100a-panel-ev-charger-upgrade\/\">Dimenzov\u00e1n\u00ed jisti\u010d\u016f pro 7kW a 22kW nab\u00edje\u010dky EV<\/a><\/li>\n<\/ul>\n<\/div>\n<div class=\"simg-pop-btn\" style=\"top: 283.828px; left: 14px; display: none;\"><\/div>\n<div class=\"simg-pop-btn\" style=\"top: 283.828px; left: 14px; display: none;\"><\/div>\n<div class=\"simg-pop-btn\" style=\"top: 3215.05px; left: 14px; display: none;\"><\/div>\n<div class=\"simg-pop-btn\" style=\"top: 3215.05px; left: 14px; display: none;\"><\/div>\n<div class=\"simg-pop-btn\" style=\"top: 2357.05px; left: 14px; display: none;\"><\/div>\n<div class=\"simg-pop-btn\" style=\"top: 2357.05px; left: 14px; display: none;\"><\/div>\n<div class=\"simg-pop-btn\" style=\"top: 283.828px; left: 14px; display: none;\"><\/div>\n<div class=\"simg-pop-btn\" style=\"top: 4434.05px; left: 14px; display: none;\"><\/div>\n<div class=\"simg-pop-btn\" style=\"top: 4434.05px; left: 14px; display: none;\"><\/div>\n<div class=\"simg-pop-btn\" style=\"top: 2386.75px; left: 14px; display: none;\"><\/div>\n<div class=\"simg-pop-btn\" style=\"top: 2386.75px; left: 14px; display: none;\"><\/div>","protected":false},"excerpt":{"rendered":"<p>Understanding Electrical Derating: Why It Matters for Safe Installations Electrical derating is the systematic reduction of a conductor&#8217;s current-carrying capacity (ampacity) to account for real-world installation conditions that deviate from standard testing environments. When cables operate in high temperatures, at elevated altitudes, or bundled with other conductors, their ability to dissipate heat diminishes significantly. Without [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":21210,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"inline_featured_image":false,"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[1],"tags":[],"class_list":["post-21209","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"_links":{"self":[{"href":"https:\/\/test.viox.com\/cs\/wp-json\/wp\/v2\/posts\/21209","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/test.viox.com\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/test.viox.com\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/test.viox.com\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/test.viox.com\/cs\/wp-json\/wp\/v2\/comments?post=21209"}],"version-history":[{"count":3,"href":"https:\/\/test.viox.com\/cs\/wp-json\/wp\/v2\/posts\/21209\/revisions"}],"predecessor-version":[{"id":21213,"href":"https:\/\/test.viox.com\/cs\/wp-json\/wp\/v2\/posts\/21209\/revisions\/21213"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/test.viox.com\/cs\/wp-json\/wp\/v2\/media\/21210"}],"wp:attachment":[{"href":"https:\/\/test.viox.com\/cs\/wp-json\/wp\/v2\/media?parent=21209"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/test.viox.com\/cs\/wp-json\/wp\/v2\/categories?post=21209"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/test.viox.com\/cs\/wp-json\/wp\/v2\/tags?post=21209"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}