{"id":2063,"date":"2026-09-01T14:39:22","date_gmt":"2026-09-01T06:39:22","guid":{"rendered":"https:\/\/jutrion.com\/?p=2063"},"modified":"2026-09-01T14:39:24","modified_gmt":"2026-09-01T06:39:24","slug":"hybrid-solar-inverter-ats-sizing","status":"publish","type":"post","link":"https:\/\/jutrion.com\/fr\/hybrid-solar-inverter-ats-sizing\/","title":{"rendered":"Comment dimensionner un ATS pour les onduleurs solaires hybrides : commutation de secours connect\u00e9e au r\u00e9seau vs hors r\u00e9seau expliqu\u00e9e"},"content":{"rendered":"<p class=\"wp-block-paragraph\"><strong>Pour dimensionner un ATS pour un onduleur solaire hybride, identifiez d'abord ce que le commutateur va r\u00e9ellement transf\u00e9rer.<\/strong>&nbsp;Do not select it from PV-array kilowatts alone. At the installed point, compare the maximum grid pass-through current, the inverter&#8217;s maximum backup-output current, and the design current of the transferred-load panel. Use the highest current that can legitimately pass through the ATS, then verify pole arrangement, short-circuit duty, utilization category, transfer logic, and compatibility with the inverter&#8217;s approved backup architecture.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Cette distinction est importante car \u201c raccord\u00e9 au r\u00e9seau \u201d, \u201c hybride \u201d et \u201c hors r\u00e9seau \u201d d\u00e9crivent des comportements \u00e9lectriques diff\u00e9rents. Un onduleur photovolta\u00efque conventionnel asservi au r\u00e9seau cesse normalement d'alimenter pendant une coupure de r\u00e9seau prolong\u00e9e. Un onduleur hybride peut contenir un relais de transfert interne et une sortie de secours d\u00e9di\u00e9e. Un onduleur hors r\u00e9seau peut former son propre bus CA et n'utiliser le r\u00e9seau ou un g\u00e9n\u00e9rateur que comme entr\u00e9e alternative. Installer le m\u00eame ATS g\u00e9n\u00e9rique dans les trois syst\u00e8mes peut produire des d\u00e9clenchements intempestifs, des charges de secours mortes, des commandes de transfert conflictuelles ou un chemin parall\u00e8le dangereux.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ce guide explique comment \u00e9tablir la bonne limite de l'ATS, calculer le courant et sp\u00e9cifier la configuration de commutation pour chaque architecture. Il compl\u00e8te notre&nbsp;<a href=\"https:\/\/jutrion.com\/fr\/automatic-transfer-switch-sizing\/\">guide g\u00e9n\u00e9ral de dimensionnement des commutateurs de transfert automatiques<\/a>, en se concentrant sp\u00e9cifiquement sur les syst\u00e8mes solaires hybrides et de secours par batterie.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-1\">R\u00e9ponse rapide : quelle valeur nominale doit contr\u00f4ler la taille de l'ATS ?<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Le courant d\u00e9terminant d\u00e9pend de l'emplacement de l'ATS :<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Emplacement de l\u2019inverseur de source<\/th><th>Sources s\u00e9lectionn\u00e9es<\/th><th>Base de courant<\/th><th>Erreur courante<\/th><\/tr><\/thead><tbody><tr><td>Avant l'entr\u00e9e CA de l'onduleur<\/td><td>R\u00e9seau et g\u00e9n\u00e9rateur<\/td><td>Courant d'entr\u00e9e CA ou de passage maximal autoris\u00e9, demande de charge transf\u00e9r\u00e9e et limite de source<\/td><td>Dimensionnement uniquement \u00e0 partir des kW de sortie de l'onduleur<\/td><\/tr><tr><td>Apr\u00e8s la sortie de secours<\/td><td>Sortie de secours de l'onduleur et d\u00e9rivation r\u00e9seau<\/td><td>Courant cr\u00e9dible le plus \u00e9lev\u00e9 d\u00e9livr\u00e9 au tableau de charges de secours<\/td><td>Utilisation des kW du champ photovolta\u00efque au lieu du courant du tableau de secours<\/td><\/tr><tr><td>Limite de service de l'ensemble du b\u00e2timent<\/td><td>Source utilitaire et source d'\u00eelotage intentionnel<\/td><td>Calcul de service\/charge plus valeur nominale approuv\u00e9e de l'interface de secours<\/td><td>Ajout d'un ATS g\u00e9n\u00e9rique \u00e0 un syst\u00e8me n\u00e9cessitant une interface de secours certifi\u00e9e<\/td><\/tr><tr><td>Bus CA hors r\u00e9seau<\/td><td>Onduleur et g\u00e9n\u00e9rateur ou d\u00e9rivation utilitaire<\/td><td>Maximum transferred-load current and both sources&#8217; continuous limits<\/td><td>Autoriser deux contr\u00f4leurs ind\u00e9pendants \u00e0 connecter des sources sans verrouillage coordonn\u00e9<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">La taille de ch\u00e2ssis s\u00e9lectionn\u00e9e ne doit pas \u00eatre inf\u00e9rieure au courant de conception maximal traversant le commutateur. Cependant, les amp\u00e8res seuls ne compl\u00e8tent pas la sp\u00e9cification. L'ATS final doit \u00e9galement convenir \u00e0 la tension du syst\u00e8me, au nombre de phases, \u00e0 la disposition du neutre et de la mise \u00e0 la terre, au niveau de d\u00e9faut attendu, \u00e0 la m\u00e9thode de transfert et aux r\u00e8gles d'installation applicables.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-2\">Commencez par l'architecture, pas par le catalogue d'ATS<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Avant de calculer le courant, tracez une ligne de chaque source possible vers les charges. Marquez le point de connexion utilitaire, l'entr\u00e9e r\u00e9seau de l'onduleur, la sortie de secours de l'onduleur, la batterie, le g\u00e9n\u00e9rateur, le tableau de charges essentielles et chaque dispositif capable d'ouvrir ou de fermer un chemin de source. Si le m\u00e9canisme de commutation, le contr\u00f4leur, la d\u00e9tection de source et le verrouillage ne sont pas encore familiers, consultez&nbsp;<a href=\"https:\/\/jutrion.com\/fr\/what-is-ats-how-to-select\/\">comment fonctionne un commutateur de transfert automatique et comment en s\u00e9lectionner un<\/a>&nbsp;avant de finaliser le sch\u00e9ma unifilaire. Le sch\u00e9ma doit rendre impossible la connexion simultan\u00e9e du r\u00e9seau et d'une source d'\u00eelotage non synchronis\u00e9e.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"341\" src=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/01-grid-tied-hybrid-off-grid-ats-architecture-1200x400-1-1024x341.png\" alt=\"\" class=\"wp-image-2065\" srcset=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/01-grid-tied-hybrid-off-grid-ats-architecture-1200x400-1-1024x341.png 1024w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/01-grid-tied-hybrid-off-grid-ats-architecture-1200x400-1-300x100.png 300w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/01-grid-tied-hybrid-off-grid-ats-architecture-1200x400-1-18x6.png 18w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/01-grid-tied-hybrid-off-grid-ats-architecture-1200x400-1-768x256.png 768w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/01-grid-tied-hybrid-off-grid-ats-architecture-1200x400-1.png 1200w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\"><em>Architectures d'onduleurs raccord\u00e9s au r\u00e9seau, hybrides avec secours et hors r\u00e9seau montrant diff\u00e9rentes positions d'ATS.<\/em><\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Le d\u00e9partement de l'\u00c9nergie des \u00c9tats-Unis distingue les onduleurs asservis au r\u00e9seau, qui n\u00e9cessitent un r\u00e9seau fonctionnel, des onduleurs formateurs de r\u00e9seau qui peuvent fonctionner lorsque le r\u00e9seau est indisponible. Il note \u00e9galement que les onduleurs ordinaires raccord\u00e9s au r\u00e9seau se d\u00e9connectent lors de perturbations plus importantes ou prolong\u00e9es du r\u00e9seau. C'est pourquoi un ATS ne peut pas transformer un onduleur standard raccord\u00e9 au r\u00e9seau en source de secours. Un secours intentionnel n\u00e9cessite un onduleur et une configuration d'isolation sp\u00e9cifiquement con\u00e7us pour le fonctionnement en \u00eelotage.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-medium-font-size wp-elements-3\">Architecture 1 : photovolta\u00efque conventionnel raccord\u00e9 au r\u00e9seau sans secours<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Un onduleur photovolta\u00efque conventionnel raccord\u00e9 au r\u00e9seau fonctionne en parall\u00e8le avec le r\u00e9seau et exporte ou compense l'\u00e9nergie tant que le r\u00e9seau est sain. Pendant une coupure, la protection anti-\u00eelotage d\u00e9connecte l'onduleur. Il n'existe aucune source CA alternative stable qu'un ATS puisse s\u00e9lectionner.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Dans cette architecture, installer un ATS entre le r\u00e9seau et la maison ne fait pas continuer \u00e0 fonctionner le syst\u00e8me photovolta\u00efque. L'onduleur a toujours besoin d'une r\u00e9f\u00e9rence r\u00e9seau valide et n'est pas autoris\u00e9 \u00e0 alimenter un circuit isol\u00e9 \u00e0 moins d'\u00eatre con\u00e7u et approuv\u00e9 pour former cet \u00eelotage. Si un secours en cas de coupure est requis, l'architecture du syst\u00e8me doit changer : g\u00e9n\u00e9ralement en ajoutant une batterie compatible, une fonction d'onduleur formateur de r\u00e9seau, une interface de secours et une limite de charges essentielles.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-medium-font-size wp-elements-4\">Architecture 2 : onduleur hybride avec dispositif de transfert interne<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Many hybrid inverters have separate grid and backup terminals. Internally, a transfer device isolates the utility and supplies a designated backup output from the battery and inverter during an outage. In this case, the inverter&#8217;s documentation\u2014not a generic diagram\u2014defines the permitted neutral arrangement, protective devices, backup-panel size, reconnection sequence, and whether an external ATS is allowed.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">An additional ATS may still serve a legitimate purpose. For example, it can bypass a failed inverter and reconnect the essential-load panel directly to the utility. In that arrangement, the ATS is not creating the solar island. It is selecting between the inverter&#8217;s backup output and a grid bypass. The ATS current rating must therefore cover the maximum current available on either of those paths.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Certaines plateformes hybrides utilisent plut\u00f4t un contr\u00f4leur syst\u00e8me d\u00e9di\u00e9 ou une interface de secours qui contient d\u00e9j\u00e0 la fonction de transfert. Remplacer ou dupliquer cette fonction avec un ATS polyvalent peut compromettre la surveillance du syst\u00e8me, le contr\u00f4le du neutre, la logique anti-\u00eelotage ou la certification du fabricant. Traitez \u201c commutateur de transfert interne \u201d, \u201c interface de secours \u201d et \u201c ATS de d\u00e9rivation externe \u201d comme trois composants diff\u00e9rents jusqu'\u00e0 ce que le sch\u00e9ma unifilaire approuv\u00e9 prouve le contraire.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-medium-font-size wp-elements-5\">Architecture 3 : Onduleur hors r\u00e9seau ou formateur de r\u00e9seau avec entr\u00e9e CA alternative<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Un onduleur hors r\u00e9seau \u00e9tablit normalement la tension et la fr\u00e9quence pour le bus CA local. Un r\u00e9seau public ou un g\u00e9n\u00e9rateur peut se connecter \u00e0 une entr\u00e9e CA afin que l'onduleur\/chargeur puisse transf\u00e9rer les charges, charger la batterie ou soutenir l'alimentation. De nombreux onduleurs\/chargeurs contiennent d\u00e9j\u00e0 un relais de transfert interne. Si la conception utilise un ATS externe, celui-ci peut s\u00e9lectionner le r\u00e9seau public versus le g\u00e9n\u00e9rateur \u00e0 l'entr\u00e9e de l'onduleur, ou la sortie de l'onduleur versus une source de d\u00e9rivation au panneau de charge.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Those two positions are not interchangeable. An input-side ATS sees the current accepted and passed through by the inverter\/charger. An output-side bypass ATS sees the current demanded by the transferred loads. The input-side controller may also need generator start\/stop contacts, warm-up time, voltage and frequency acceptance windows, and a cool-down sequence. The output-side device must avoid back-feeding the inverter output when bypass is active unless the manufacturer&#8217;s design expressly permits it.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-large-font-size\">Les quatre valeurs de courant que vous devez enregistrer<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Une fiche de s\u00e9lection fiable enregistre quatre valeurs de courant plut\u00f4t qu'un seul chiffre de puissance solaire.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"341\" src=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/02-hybrid-inverter-ats-current-boundaries-1200x400-1-1024x341.png\" alt=\"\" class=\"wp-image-2066\" srcset=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/02-hybrid-inverter-ats-current-boundaries-1200x400-1-1024x341.png 1024w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/02-hybrid-inverter-ats-current-boundaries-1200x400-1-300x100.png 300w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/02-hybrid-inverter-ats-current-boundaries-1200x400-1-18x6.png 18w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/02-hybrid-inverter-ats-current-boundaries-1200x400-1-768x256.png 768w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/02-hybrid-inverter-ats-current-boundaries-1200x400-1.png 1200w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\"><em>Chemins de courant ATS d'onduleur hybride comparant une sortie de secours de 35 A, une d\u00e9rivation r\u00e9seau de 63 A et un panneau de charge de 46 A.<\/em><\/figcaption><\/figure>\n\n\n\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-medium-font-size wp-elements-6\">Courant de conception des charges transf\u00e9r\u00e9es<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Il s'agit du courant requis par les charges connect\u00e9es en aval de l'ATS. Ce n'est pas automatiquement la capacit\u00e9 du service principal ni automatiquement la capacit\u00e9 de l'onduleur. Un commutateur de transfert pour b\u00e2timent entier peut porter la demande calcul\u00e9e du b\u00e2timent. Un ATS pour charges essentielles peut ne porter que la r\u00e9frig\u00e9ration, l'\u00e9clairage, les commandes, les communications, les prises s\u00e9lectionn\u00e9es et d'autres circuits prioritaires.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Utilisez le calcul de charge du projet et le code \u00e9lectrique applicable. Tenez compte des charges continues, des moteurs, des transformateurs, des compresseurs et du fonctionnement simultan\u00e9. Si le d\u00e9lestage fait partie de la conception, documentez quelles charges se d\u00e9connectent avant d'utiliser la valeur r\u00e9duite.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-medium-font-size wp-elements-7\">Courant maximal de sortie de secours de l'onduleur<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Lisez la fiche technique ou le manuel d'installation de l'onduleur. Pr\u00e9f\u00e9rez son courant maximal continu de sortie de secours d\u00e9clar\u00e9 \u00e0 un calcul \u00e0 partir de la puissance marketing. Si seule la puissance apparente est disponible, les calculs CA de base sont :<\/p>\n\n\n\n<div class=\"wp-block-group has-palette-color-8-color has-palette-color-9-background-color has-text-color has-background has-link-color wp-elements-8 is-layout-constrained wp-block-group-is-layout-constrained\">\n<p class=\"wp-block-paragraph\"><strong>Monophas\u00e9 :<\/strong>&nbsp;I = S \u00f7 V<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Triphas\u00e9 :<\/strong>&nbsp;I = S \u00f7 (\u221a3 \u00d7 V)<\/p>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\">For a 10 kVA, 230 V single-phase output, the ideal current is approximately 43.5 A. For a 30 kVA, 400 V three-phase output, it is approximately 43.3 A per phase. These values are starting points, not permission to ignore the manufacturer&#8217;s current limit, overload curve, phase-imbalance limit, or ambient derating.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-medium-font-size wp-elements-9\">Courant de passage ou de d\u00e9rivation du r\u00e9seau<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">C'est fr\u00e9quemment la valeur d\u00e9terminante. Un onduleur hybride nominal de 8 kW de sortie de secours peut permettre \u00e0 un courant de r\u00e9seau plus \u00e9lev\u00e9 de traverser son relais interne tant que le r\u00e9seau public est disponible. De m\u00eame, un chemin de d\u00e9rivation externe peut alimenter directement l'ensemble du tableau de charges essentielles depuis le r\u00e9seau.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If 63 A can pass through the ATS in grid mode, selecting a 40 A ATS because the inverter produces only 8 kW is incorrect. The switch contacts and terminals still carry the 63 A path. Record the inverter&#8217;s maximum AC-input\/pass-through current, the bypass breaker rating, and the downstream load calculation, then use the most restrictive coordinated design.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-medium-font-size wp-elements-10\">Courant maximal permis par chaque source et dispositif de protection<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">L'alimentation du r\u00e9seau, le disjoncteur du g\u00e9n\u00e9rateur, la protection de sortie de l'onduleur, les conducteurs et le dispositif principal du tableau de distribution \u00e9tablissent les limites. L'ATS ne cr\u00e9e pas de capacit\u00e9 de source suppl\u00e9mentaire, et son calibre de courant ne prot\u00e8ge pas les c\u00e2bles \u00e0 lui seul. Un commutateur de transfert de classe PC s'appuie g\u00e9n\u00e9ralement sur une protection contre les surintensit\u00e9s en amont coordonn\u00e9e ; un agencement de classe CB int\u00e8gre les fonctions de disjoncteur. S\u00e9lectionnez et v\u00e9rifiez toute la cha\u00eene de protection.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-11\">Une m\u00e9thode pratique de dimensionnement de l'ATS pour les onduleurs hybrides<\/h2>\n<\/blockquote>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Confirmez que l'onduleur peut former un \u00eelot.<\/strong>&nbsp;S'il est uniquement photovolta\u00efque et suiveur de r\u00e9seau, arr\u00eatez : il n'y a pas de source de secours valide pour l'ATS.<\/li>\n\n\n\n<li><strong>Use the manufacturer&#8217;s approved architecture.<\/strong>&nbsp;Identifiez l'interface de secours requise, le relais de transfert interne, le commutateur externe compatible ou l'agencement de d\u00e9rivation autoris\u00e9.<\/li>\n\n\n\n<li><strong>Marquez la position de l'ATS.<\/strong>&nbsp;Indiquez exactement quelles deux sources se connectent \u00e0 la Source I et \u00e0 la Source II, et quel tableau se connecte \u00e0 la sortie commune.<\/li>\n\n\n\n<li><strong>D\u00e9finissez les charges transf\u00e9r\u00e9es.<\/strong>&nbsp;Utilisez un tableau des charges essentielles ou le calcul de demande de l'ensemble du b\u00e2timent plut\u00f4t que d'additionner les plaques signal\u00e9tiques des appareils sans discernement.<\/li>\n\n\n\n<li><strong>Notez le courant de sortie de secours.<\/strong>&nbsp;Utilisez le courant maximal d\u00e9clar\u00e9 et notez s\u00e9par\u00e9ment la capacit\u00e9 de surcharge de courte dur\u00e9e.<\/li>\n\n\n\n<li><strong>Notez le courant de passage ou de d\u00e9rivation du r\u00e9seau.<\/strong>&nbsp;V\u00e9rifiez la limite d'entr\u00e9e de l'onduleur, le calibre du relais interne, l'alimentation de d\u00e9rivation et le dispositif principal du tableau.<\/li>\n\n\n\n<li><strong>S\u00e9lectionnez le courant continu.<\/strong>&nbsp;L'ATS doit supporter le courant maximal cr\u00e9dible \u00e0 sa position install\u00e9e, sous r\u00e9serve des r\u00e8gles du code, du d\u00e9classement, de la temp\u00e9rature de l'enceinte et des instructions du fabricant.<\/li>\n\n\n\n<li><strong>Effectuez les v\u00e9rifications hors amp\u00e9rage.<\/strong>&nbsp;V\u00e9rifiez la tension, la fr\u00e9quence, les phases, les p\u00f4les, le traitement du neutre, le calibre de court-circuit, la cat\u00e9gorie d'emploi, le temps de transfert, la d\u00e9tection, la tension de commande et le verrouillage.<\/li>\n\n\n\n<li><strong>Validez chaque \u00e9tat de fonctionnement.<\/strong>&nbsp;Passez en revue le fonctionnement normal sur r\u00e9seau, la panne de r\u00e9seau, la d\u00e9faillance de l'onduleur, la batterie d\u00e9charg\u00e9e, le fonctionnement du g\u00e9n\u00e9rateur, la d\u00e9rivation de maintenance et le retour du r\u00e9seau.<\/li>\n<\/ol>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-12\">Exemple concret : onduleur hybride de 8 kW avec d\u00e9rivation r\u00e9seau<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Consid\u00e9rez un syst\u00e8me monophas\u00e9 illustratif de 230 V avec ces valeurs de conception :<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Calibre de secours de l'onduleur hybride : 8 kVA en continu<\/li>\n\n\n\n<li>Courant maximal de sortie de secours d\u00e9clar\u00e9 : 35 A<\/li>\n\n\n\n<li>Courant de passage du r\u00e9seau autoris\u00e9 : 63 A<\/li>\n\n\n\n<li>Courant de conception du tableau de charges essentielles : 46 A lorsque le r\u00e9seau est disponible<\/li>\n\n\n\n<li>Limite de gestion de charge en mode secours : 32 A<\/li>\n\n\n\n<li>Position de l'ATS externe : sortie de secours de l'onduleur contre d\u00e9rivation directe du r\u00e9seau<\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"341\" src=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/03-8kva-hybrid-inverter-ats-sizing-example-1200x400-1-1024x341.png\" alt=\"\" class=\"wp-image-2067\" srcset=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/03-8kva-hybrid-inverter-ats-sizing-example-1200x400-1-1024x341.png 1024w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/03-8kva-hybrid-inverter-ats-sizing-example-1200x400-1-300x100.png 300w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/03-8kva-hybrid-inverter-ats-sizing-example-1200x400-1-18x6.png 18w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/03-8kva-hybrid-inverter-ats-sizing-example-1200x400-1-768x256.png 768w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/03-8kva-hybrid-inverter-ats-sizing-example-1200x400-1.png 1200w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\"><em>Exemple concret de dimensionnement d'ATS pour un onduleur hybride de 8 kVA 230 V avec des chemins de secours de 35 A et de r\u00e9seau de 63 A.<\/em><\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Le courant approximatif de l'onduleur \u00e0 partir de la puissance apparente est de 8 000 \u00f7 230 = 34,8 A, ce qui est coh\u00e9rent avec la sortie d\u00e9clar\u00e9e de 35 A. Mais un ATS de 40 A n'est pas automatiquement appropri\u00e9. En mode d\u00e9rivation r\u00e9seau, le tableau de charges essentielles peut tirer 46 A et le chemin de source est autoris\u00e9 jusqu'\u00e0 63 A.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">\u00c0 cet emplacement, la s\u00e9lection du courant de l'ATS est d\u00e9termin\u00e9e par le chemin de d\u00e9rivation r\u00e9seau et de charges transf\u00e9r\u00e9es, et non par la sortie de 8 kVA de l'onduleur. Une classe de 63 A peut \u00eatre la classe de courant minimale pratique si toutes les v\u00e9rifications applicables de charge continue, de temp\u00e9rature, d'enceinte, de bornes et de code local le permettent. Un cadre de 80 A peut \u00eatre s\u00e9lectionn\u00e9 lorsque la conception coordonn\u00e9e, le d\u00e9classement en fonction de la temp\u00e9rature ambiante, le raccordement des conducteurs ou la norme du projet exige plus de marge. La r\u00e9ponse finale ne peut pas \u00eatre obtenue \u00e0 partir de 8 kW seuls.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The load-management controller must keep backup-mode demand within the inverter&#8217;s 35 A capability. Oversizing the ATS to 63 A or 80 A does not make the inverter capable of supplying 46 A during an outage. That is a separate energy and power-management constraint.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-13\">Transfert de toute la maison ou transfert des charges essentielles ?<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Ce choix modifie \u00e0 la fois la taille de l'ATS et le comportement du syst\u00e8me. Un agencement de transfert de toute la maison place la limite de secours autour de la majeure partie ou de la totalit\u00e9 de la distribution du b\u00e2timent. L'ATS et l'interface associ\u00e9e peuvent donc devoir correspondre \u00e0 l'alimentation ou \u00e0 la demande calcul\u00e9e, m\u00eame lorsque l'onduleur ne peut fournir qu'une fraction de ce courant. Un secours r\u00e9ussi de toute la maison d\u00e9pend g\u00e9n\u00e9ralement d'une gestion automatique des charges qui d\u00e9connecte le chauffage de l'eau, la climatisation de grande taille, la recharge des v\u00e9hicules \u00e9lectriques, la cuisson \u00e9lectrique ou d'autres charges avant que l'onduleur ne soit surcharg\u00e9.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"341\" src=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/04-whole-home-vs-essential-load-backup-1200x400-1-1024x341.png\" alt=\"\" class=\"wp-image-2068\" srcset=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/04-whole-home-vs-essential-load-backup-1200x400-1-1024x341.png 1024w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/04-whole-home-vs-essential-load-backup-1200x400-1-300x100.png 300w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/04-whole-home-vs-essential-load-backup-1200x400-1-18x6.png 18w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/04-whole-home-vs-essential-load-backup-1200x400-1-768x256.png 768w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/04-whole-home-vs-essential-load-backup-1200x400-1.png 1200w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\"><em>Secours hybride de toute la maison avec d\u00e9lestage compar\u00e9 \u00e0 un tableau de secours d\u00e9di\u00e9 aux charges essentielles.<\/em><\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">An essential-load arrangement creates a smaller downstream panel. Only the selected circuits transfer to inverter power. This often allows a lower ATS current rating, smaller conductors, and more predictable battery autonomy. It also makes the backup-mode current limit visible: if the panel contains 32 A of managed demand, the designer can verify that against the inverter&#8217;s declared output rather than hoping occupants will avoid simultaneous loads.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Utilisez la d\u00e9cision suivante :<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Choisir un panneau de charges essentielles<\/strong>&nbsp;lorsque la sortie de l'onduleur est sensiblement inf\u00e9rieure \u00e0 la capacit\u00e9 de service, que l'\u00e9nergie de la batterie est limit\u00e9e, ou qu'une priorisation fiable des charges est plus importante que la commodit\u00e9.<\/li>\n\n\n\n<li><strong>Consider whole-home transfer<\/strong>&nbsp;when the approved system controller supports it, the inverter and battery can sustain the intended demand, and automatic load shedding is documented.<\/li>\n\n\n\n<li><strong>Do not reduce ATS current merely because backup-mode software limits the inverter.<\/strong>&nbsp;If the same contacts carry full grid-mode demand, size them for that grid path.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">For procurement, state both numbers: \u201cATS continuous current at installed boundary\u201d and \u201cmaximum permitted backup-mode load.\u201d They answer different questions and prevent installers from treating an oversized switch as evidence of adequate inverter capacity.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-14\">Three-Phase Hybrid Inverters Need Additional Checks<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">A three-phase current calculation assumes balanced apparent power. Real backup panels may be unbalanced, and some hybrid inverters impose a maximum current per phase or a maximum permitted phase imbalance. For example, a nominal 30 kVA, 400 V three-phase inverter corresponds to approximately 43.3 A per phase:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>I = 30,000 \u00f7 (1.732 \u00d7 400) = 43.3 A per phase<\/strong><\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"341\" src=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/05-three-phase-hybrid-inverter-4p-ats-1200x400-1-1024x341.png\" alt=\"\" class=\"wp-image-2069\" srcset=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/05-three-phase-hybrid-inverter-4p-ats-1200x400-1-1024x341.png 1024w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/05-three-phase-hybrid-inverter-4p-ats-1200x400-1-300x100.png 300w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/05-three-phase-hybrid-inverter-4p-ats-1200x400-1-18x6.png 18w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/05-three-phase-hybrid-inverter-4p-ats-1200x400-1-768x256.png 768w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/05-three-phase-hybrid-inverter-4p-ats-1200x400-1.png 1200w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\"><em>Three-phase hybrid inverter connected through a four-pole ATS with L1, L2, L3, neutral, and phase imbalance.<\/em><\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">That result does not prove a 50 A ATS is suitable. Check whether the grid pass-through rating is 63 A, 80 A, or another value; whether the backup panel can concentrate single-phase loads on one phase; and whether the inverter can energize all three phases during island operation. A 4 kW load added to one phase represents roughly 17.4 A at 230 V even though total three-phase kVA still appears acceptable.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Build a phase schedule for the essential loads. Keep large single-phase loads distributed where possible, and verify the worst phase rather than only the average. If the inverter permits 40 A on each phase but the grid bypass permits 63 A, the ATS at a backup-output\/grid-bypass boundary may still require a 63 A current class. Backup-mode load controls must then prevent any phase from exceeding the inverter limit.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Also confirm what happens when one phase fails. Some ATS controllers transfer on phase loss; some hybrid inverters disconnect the complete output; and some applications require a specific delay to prevent operation on unstable utility power. Phase-sequence monitoring may be necessary for motors and rotating equipment. The controller specification should state undervoltage, overvoltage, phase-loss, phase-sequence, and frequency behavior\u2014not merely \u201cautomatic.\u201d<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-15\">Adding a Generator to a Hybrid Solar System<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">A generator creates a third source even though a conventional ATS normally selects only two. The design therefore needs a clear hierarchy. Common architectures include:<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Utility versus generator at the inverter AC input.<\/strong>&nbsp;The inverter\/charger receives whichever external AC source the input ATS selects, while its internal relay manages pass-through and battery operation.<\/li>\n\n\n\n<li><strong>Utility on the inverter grid input and generator on a dedicated generator input.<\/strong>&nbsp;The hybrid controller manages both sources without an extra source-selection ATS, provided the model supports this arrangement.<\/li>\n\n\n\n<li><strong>Inverter backup output versus generator bypass at the essential-load panel.<\/strong>&nbsp;This can preserve loads if the inverter or battery becomes unavailable, but the generator branch and inverter output must never be paralleled unintentionally.<\/li>\n<\/ol>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"341\" src=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/06-generator-hybrid-inverter-input-ats-1200x400-1-1024x341.png\" alt=\"\" class=\"wp-image-2070\" srcset=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/06-generator-hybrid-inverter-input-ats-1200x400-1-1024x341.png 1024w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/06-generator-hybrid-inverter-input-ats-1200x400-1-300x100.png 300w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/06-generator-hybrid-inverter-input-ats-1200x400-1-18x6.png 18w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/06-generator-hybrid-inverter-input-ats-1200x400-1-768x256.png 768w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/06-generator-hybrid-inverter-input-ats-1200x400-1.png 1200w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\"><em>Grid and generator source selection through an input ATS feeding a battery-backed hybrid inverter and essential loads.<\/em><\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">For an input-side utility\/generator ATS, calculate generator current from its kVA rating and compare it with the inverter&#8217;s maximum accepted AC-input current. Suppose a 15 kVA, 230 V single-phase generator supplies an inverter charger. Its nominal current is about 65.2 A. If the inverter accepts only 50 A, its settings or upstream protection may limit charging and pass-through current, but the ATS source circuit still has to be coordinated with the generator breaker, conductors, and actual load path. Do not assume the software input limit is a substitute for circuit protection.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Generator operation adds control requirements that solar-only diagrams do not show: start signal, crank attempts, warm-up delay, source-available verification, minimum run time, cool-down, exercise schedule, low-fuel or fault feedback, and battery state-of-charge thresholds. A basic voltage-sensing ATS can transfer loads, but it may not coordinate charging power or prevent the inverter charger from overloading a small generator. Where the hybrid inverter manages the generator, use the specified dry contacts and control sequence. If the generator starts but the load does not transfer, follow the&nbsp;<a href=\"https:\/\/jutrion.com\/fr\/automatic-transfer-switch-not-switching-to-generator\/\">ATS generator transfer diagnostic sequence<\/a>&nbsp;to locate the first missing controller or power-path state.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Three-source systems may require two interlocked transfer stages or purpose-built multi-source switchgear. IEC 60947-6-1:2026 notes boundaries around multi-source and hybrid TSE within its scope description, so the complete assembly and controller arrangement should be verified rather than assembled from unrelated switches and assumed to be compliant.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-16\">Grid-Tied Versus Off-Grid: What Changes in the Transfer Sequence?<\/h2>\n<\/blockquote>\n\n\n\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-medium-font-size wp-elements-17\">Grid-Tied Hybrid Backup Sequence<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">In normal operation, the utility establishes the grid reference and may supply loads through the inverter&#8217;s pass-through path. When grid voltage or frequency leaves the permitted window, the approved isolation device opens the utility connection. Only after isolation is confirmed can the grid-forming inverter energize the backup bus. When the utility returns and remains stable for the configured delay, the system resynchronizes or performs an open transition according to its approved control logic.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"341\" src=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/07-hybrid-inverter-grid-failure-transfer-sequence-1200x400-1-1024x341.png\" alt=\"\" class=\"wp-image-2071\" srcset=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/07-hybrid-inverter-grid-failure-transfer-sequence-1200x400-1-1024x341.png 1024w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/07-hybrid-inverter-grid-failure-transfer-sequence-1200x400-1-300x100.png 300w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/07-hybrid-inverter-grid-failure-transfer-sequence-1200x400-1-18x6.png 18w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/07-hybrid-inverter-grid-failure-transfer-sequence-1200x400-1-768x256.png 768w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/09\/07-hybrid-inverter-grid-failure-transfer-sequence-1200x400-1.png 1200w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\"><em>Five-step hybrid inverter transfer sequence from grid outage and isolation to energized essential loads.<\/em><\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">A generic ATS that merely detects \u201cno voltage\u201d may not know whether the inverter has completed isolation, whether its backup bus is stable, or whether reconnection is permitted. That is why hybrid systems often rely on an integrated controller, a dedicated backup interface, or dry-contact coordination specified by the inverter manufacturer.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-medium-font-size wp-elements-18\">Off-Grid Source-Selection Sequence<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">In an off-grid installation, the inverter is normally the grid-forming source. The alternate utility or generator input becomes acceptable only after its voltage and frequency stabilize. An input-side ATS may choose between utility and generator before feeding the inverter\/charger. The inverter&#8217;s internal relay then decides whether to pass the accepted source through or continue supporting the loads from battery power.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If a second, output-side ATS provides maintenance bypass, its logic must be coordinated with the inverter. The design should prevent a bypass source from being connected to an energized inverter output unless the equipment is specifically intended for synchronized parallel operation. Mechanical and electrical interlocking should not depend on software commands alone.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-19\">Poles, Neutral Switching, and Earthing<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Do not choose 2P, 3P, or 4P solely from a simple \u201csingle phase versus three phase\u201d rule. Determine whether the neutral must remain solidly connected or be switched, how each source is earthed, where the neutral-to-earth bond exists, and how residual-current protection behaves in every source state.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A single-phase line-and-neutral system may use a two-pole transfer arrangement where both conductors must be switched. A three-phase four-wire system may require a four-pole ATS when the alternate source creates a separately derived or differently referenced neutral. Other systems deliberately keep a common neutral. The correct arrangement depends on the inverter design, local code, utility requirements, and the manufacturer&#8217;s approved diagram.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Incorrect neutral handling can create parallel neutral paths, circulating current, ineffective residual-current protection, nuisance tripping, or a floating backup system. Make a neutral-and-earth state table for utility mode, island mode, generator mode, and maintenance bypass. If the table does not show one intentional bonding strategy in each state, the design is not ready for installation.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-20\">Short-Circuit Duty Is Not the Same as Continuous Current<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Hybrid systems have two very different fault-current sources. The utility can deliver a high prospective short-circuit current. An inverter normally limits output electronically and may supply only a modest multiple of rated current for a short duration. The ATS still has to withstand and, where required, close onto the worst fault duty available at its installed point.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Check the available fault current from every connected source, the upstream protective device, and the ATS manufacturer&#8217;s conditional short-circuit or withstand-and-closing data. Do not assume that an inverter&#8217;s limited fault current makes a small transfer switch acceptable if the same contacts are connected to a strong utility bypass.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For IEC-oriented projects,&nbsp;<a href=\"https:\/\/webstore.iec.ch\/en\/publication\/90494\" target=\"_blank\" rel=\"noopener\">CEI 60947-6-1:2026<\/a>&nbsp;covers transfer switching equipment used to transfer a load between sources. For North American projects,&nbsp;<a href=\"https:\/\/www.ul.com\/services\/switch-certification-and-evaluation-services\" target=\"_blank\" rel=\"noopener\">UL&#8217;s switch certification overview<\/a>&nbsp;identifies UL 1008 categories for automatic and nonautomatic transfer switches. Always apply the edition and installation rules adopted by the project&#8217;s authority having jurisdiction.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-21\">Transfer Time: An ATS Is Not Automatically a UPS<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">An ATS transfer includes detection, validation, mechanical operation, and stabilization time. Even a fast switch can create an interruption long enough to reset controls, contactors, communications equipment, or computers. A hybrid inverter with an internal transfer relay may support a shorter transition than a separate electromechanical ATS, but the actual value must come from the system documentation and testing.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Classify the loads by ride-through tolerance. Lighting and refrigeration may tolerate a brief interruption. Servers, PLCs, medical equipment, and network devices may require a UPS or a no-break inverter path. Do not promise \u201cuninterrupted power\u201d from the ATS current rating.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-22\">Control and Sensing Details That Determine Whether It Works<\/h2>\n<\/blockquote>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Source sensing:<\/strong>&nbsp;Measure the voltage and frequency at the actual source terminals. PV production or battery state of charge is not the same as a healthy AC backup source.<\/li>\n\n\n\n<li><strong>Transfer delays:<\/strong>&nbsp;Prevent rapid cycling during unstable utility conditions and allow a generator or inverter bus to stabilize.<\/li>\n\n\n\n<li><strong>Preferred source:<\/strong>&nbsp;Decide whether the inverter backup output, grid bypass, or generator is the normal source for each ATS.<\/li>\n\n\n\n<li><strong>Dry contacts:<\/strong>&nbsp;Confirm voltage-free contact ratings, logic polarity, and fail-safe behavior before connecting inverter or generator controls.<\/li>\n\n\n\n<li><strong>Return logic:<\/strong>&nbsp;Define whether the system automatically returns to utility, waits for battery recovery, or requires manual approval.<\/li>\n\n\n\n<li><strong>Failure mode:<\/strong>&nbsp;Decide what happens if the inverter controller, ATS motor, sensing fuse, or communications link fails.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">For projects needing remote status, select an&nbsp;<a href=\"https:\/\/jutrion.com\/fr\/ats\/\">automatic transfer switch<\/a>&nbsp;with the required auxiliary contacts or communications options. Keep hardwired source interlocking independent from supervisory monitoring.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-23\">How to Read Inverter and ATS Datasheets Together<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">The inverter manual and ATS datasheet use different terms, so create a cross-check instead of comparing one \u201crated current\u201d line.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Inverter data<\/th><th>ATS data to compare<\/th><th>Design question<\/th><\/tr><\/thead><tbody><tr><td>Maximum continuous backup current<\/td><td>Rated operational current and utilization category<\/td><td>Can the contacts carry the inverter output continuously?<\/td><\/tr><tr><td>Maximum AC input\/pass-through current<\/td><td>Rated operational current and terminal capacity<\/td><td>Can the ATS carry the larger grid or generator path?<\/td><\/tr><tr><td>Output overload curve<\/td><td>Making\/breaking duty and load category<\/td><td>Will motor or transformer events cause transfer stress or inverter shutdown?<\/td><\/tr><tr><td>Grid and backup voltage\/frequency windows<\/td><td>Controller sensing range and adjustable thresholds<\/td><td>Will both devices agree that a source is acceptable?<\/td><\/tr><tr><td>Internal transfer time<\/td><td>ATS operating and intentional delay time<\/td><td>What interruption will the load actually experience?<\/td><\/tr><tr><td>Neutral\/earthing diagram<\/td><td>2P, 3P, or 4P switching arrangement<\/td><td>Does each operating state preserve the approved bonding system?<\/td><\/tr><tr><td>Maximum fault contribution<\/td><td>Short-circuit withstand\/conditional rating<\/td><td>Is the switch coordinated for both inverter and utility sources?<\/td><\/tr><tr><td>Dry-contact or communications interface<\/td><td>Controller inputs, outputs, and auxiliary contacts<\/td><td>Can the devices exchange permissive, fault, and position status safely?<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">If a value is missing, request it before issuing the switch specification. \u201cCompatible with solar\u201d is not an electrical rating. Likewise, \u201c63 A ATS\u201d does not state whether the device is suitable for the voltage, load category, fault level, switching sequence, or market certification.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity is-style-wide\"\/>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-24\">Common Hybrid-Inverter ATS Sizing Errors<\/h2>\n<\/blockquote>\n\n\n\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-medium-font-size wp-elements-25\">Sizing from PV Array kW<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A 12 kWp array does not mean the ATS carries 12 kW. The inverter AC rating, battery discharge limit, grid pass-through path, and transferred-load demand determine current at different locations.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-medium-font-size wp-elements-26\">Using Only the Inverter Output Rating<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The grid or generator may pass more current through an ATS than the inverter can produce. This is the most important reason to record pass-through and bypass ratings separately.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-medium-font-size wp-elements-27\">Duplicating an Internal Transfer Function<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Two automatic controllers can issue contradictory commands, create unnecessary interruptions, or bypass the inverter&#8217;s approved isolation sequence. Use a documented master-control relationship.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-medium-font-size wp-elements-28\">Assuming Any Grid-Tied Inverter Can Provide Backup<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The U.S. Department of Energy explains that grid-following inverters shut down when grid power is unavailable, while grid-forming capability is required for off-grid or backup operation. An ATS alone does not supply that capability.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-medium-font-size wp-elements-29\">Ignoring Neutral Behavior<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A current rating can be correct while the system remains unsafe because of an incorrect neutral or bonding arrangement. Review protective-conductor and residual-current operation in every transfer state.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-medium-font-size wp-elements-30\">Treating the ATS as Overcurrent Protection<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A transfer switch changes source paths. Unless the selected product is specifically a CB-class protective arrangement, coordinated breakers or fuses are still required.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity is-style-wide\"\/>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-31\">Commissioning Tests Before the System Goes Live<\/h2>\n<\/blockquote>\n\n\n\n<ol class=\"wp-block-list\">\n<li>Verify conductor identity, terminal torque, phase sequence, polarity, neutral continuity, and protective-earthing connections.<\/li>\n\n\n\n<li>Confirm the ATS source names match the actual preferred and alternate sources.<\/li>\n\n\n\n<li>Measure grid, inverter-backup, and generator voltage and frequency at the sensing points.<\/li>\n\n\n\n<li>Simulate a grid failure and confirm utility isolation occurs before the island bus is energized.<\/li>\n\n\n\n<li>Apply representative essential loads and verify backup current remains within the inverter limit.<\/li>\n\n\n\n<li>Disable or fault the inverter and verify the intended bypass response without back-feeding its output.<\/li>\n\n\n\n<li>Restore the utility and confirm the retransfer delay, source stability checks, and final operating state.<\/li>\n\n\n\n<li>Test battery-low, overload, emergency-stop, manual operation, and communications-loss states.<\/li>\n\n\n\n<li>Record transfer times, currents, alarms, controller settings, and as-built wiring changes.<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">Commissioning must be performed by qualified personnel using an approved test procedure. Utility-connected solar and battery systems can energize conductors from multiple directions even when one disconnect is open.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-32\">ATS Specification Checklist for a Hybrid Solar Project<\/h2>\n<\/blockquote>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th>Specification item<\/th><th>Project entry<\/th><\/tr><\/thead><tbody><tr><td>ATS function and location<\/td><td>Input source selector, backup-output bypass, or service isolation<\/td><\/tr><tr><td>Source I \/ Source II<\/td><td>Utility, generator, inverter backup output, or approved combination<\/td><\/tr><tr><td>Transferred-load design current<\/td><td>From the load schedule and local rules<\/td><\/tr><tr><td>Inverter backup current<\/td><td>Manufacturer&#8217;s maximum continuous value<\/td><\/tr><tr><td>Grid pass-through\/bypass current<\/td><td>Maximum permitted at the installed point<\/td><\/tr><tr><td>Rated operational current<\/td><td>Selected after load, derating, and coordination checks<\/td><\/tr><tr><td>Voltage, frequency, phases<\/td><td>Match both sources and load<\/td><\/tr><tr><td>P\u00f4les et neutre<\/td><td>Based on the approved earthing design<\/td><\/tr><tr><td>Fault-duty data<\/td><td>Available fault current and coordinated protective device<\/td><\/tr><tr><td>Transfer method<\/td><td>Open transition unless an approved synchronized method is required<\/td><\/tr><tr><td>Control and feedback<\/td><td>Sensing thresholds, delays, dry contacts, status, communications<\/td><\/tr><tr><td>Compatibility evidence<\/td><td>Inverter-approved one-line diagram and applicable certification<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-33\">Final Selection Rule<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">The correct ATS size for a hybrid solar inverter is the rating required at the switch&#8217;s real electrical boundary\u2014not the number printed beside the PV array. First prove that the system has an approved grid-forming and isolation method. Then compare transferred-load current, inverter backup-output current, and grid pass-through or bypass current. Select for the highest credible current through that location and finish the design with pole, neutral, fault-duty, transfer-time, protection, and controller checks.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For a project-specific selection, send JUTRION the one-line diagram, system voltage and phases, inverter model, backup-output current, pass-through rating, transferred-load schedule, available fault current, and required control signals. Those details allow the&nbsp;<a href=\"https:\/\/jutrion.com\/fr\/ats\/\">ATS configuration<\/a>&nbsp;to be matched to the actual hybrid or off-grid architecture.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity is-style-wide\"\/>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-34\">Questions fr\u00e9quemment pos\u00e9es<\/h2>\n<\/blockquote>\n\n\n<div id=\"rank-math-faq\" class=\"rank-math-block\">\n<div class=\"rank-math-list\">\n<div id=\"faq-question-1788243694206\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">Do I need an ATS with a hybrid solar inverter?<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>Not always. Many hybrid inverters already contain an internal transfer relay or work with a dedicated backup interface. An external ATS is appropriate only when the manufacturer&#8217;s approved architecture calls for functions such as grid-versus-generator input selection, inverter-output bypass, or maintenance redundancy. Adding another ATS without checking the approved diagram can create conflicting transfer logic.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-question-1788243711457\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">Can an ATS make a grid-tied solar inverter work during a power outage?<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>No. A conventional grid-following inverter disconnects when the utility grid is unavailable. An ATS cannot give it grid-forming capability. Backup operation requires compatible islanding equipment, an inverter designed to establish a local AC bus, and usually battery storage or another stable energy source.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-question-1788243723696\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">Should ATS size match the solar inverter kW rating?<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>Not necessarily. The ATS must be rated for the maximum current that can pass through its installed position. A hybrid inverter may provide 35 A in backup mode while permitting 63 A of grid pass-through current. If the ATS carries that grid path, the larger credible current\u2014not PV-array power or inverter kW alone\u2014controls the initial current class.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-question-1788243734552\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">How do I convert hybrid inverter kVA to ATS current?<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>For single-phase systems, divide apparent power in VA by voltage: I = S \u00f7 V. For balanced three-phase systems, use I = S \u00f7 (\u221a3 \u00d7 V). Compare the result with the inverter&#8217;s declared maximum AC current, because the nameplate limit takes precedence over an ideal calculation. Then check whether grid pass-through current or transferred-load demand is higher.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-question-1788243746857\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">Should the ATS be installed before or after the hybrid inverter?<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>It depends on its intended job. An input-side ATS may select utility or generator before the inverter\/charger. An output-side ATS may select inverter backup output or a direct grid bypass for an essential-load panel. A service-boundary transfer device may be part of a dedicated backup interface. These positions have different current, neutral, sensing, and control requirements.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-question-1788243758097\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">Do I need a 2-pole or 4-pole ATS for a solar inverter?<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>Choose the pole arrangement from the number of phases and the approved neutral-and-earthing design. Some systems retain a solid neutral; others must switch the neutral to avoid parallel paths or to accommodate a separately derived source. Do not apply a universal \u201csingle phase equals 2P\u201d or \u201cthree phase equals 4P\u201d rule without checking the inverter manual, local code, residual-current protection, and bonding arrangement.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-question-1788243770189\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">Can I use a larger ATS than the inverter output current?<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>Yes, provided the voltage, poles, utilization duty, fault rating, protection, controls, and certification are suitable. A larger ATS is commonly required when grid bypass current exceeds inverter backup current. However, the larger switch does not increase inverter output or battery capacity; backup loads must still remain within the inverter&#8217;s limit.<\/p>\n\n<\/div>\n<\/div>\n<div id=\"faq-question-1788243781488\" class=\"rank-math-list-item\">\n<h3 class=\"rank-math-question\">Is an ATS fast enough to replace a UPS?<\/h3>\n<div class=\"rank-math-answer\">\n\n<p>Not automatically. Source detection, validation, mechanical operation, and inverter stabilization can create an interruption. Sensitive computers, servers, controls, communications equipment, or medical loads may still need a UPS or a verified no-break power path. Check the complete system transfer time rather than relying on the ATS current rating.<\/p>\n\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h2 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-35\">R\u00e9f\u00e9rences<\/h2>\n<\/blockquote>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/webstore.iec.ch\/en\/publication\/90494\" target=\"_blank\" rel=\"noopener\">IEC 60947-6-1:2026 \u2014 Transfer Switching Equipment<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/www.ul.com\/services\/switch-certification-and-evaluation-services\" target=\"_blank\" rel=\"noopener\">UL Solutions \u2014 Switch Certification and Evaluation Services<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/www.energy.gov\/cmei\/systems\/solar-integration-inverters-and-grid-services-basics\" target=\"_blank\" rel=\"noopener\">U.S. Department of Energy \u2014 Solar Integration: Inverters and Grid Services Basics<\/a><\/li>\n\n\n\n<li><a href=\"https:\/\/www.energy.gov\/indianenergy\/tribal-energy-guide\/solar\" target=\"_blank\" rel=\"noopener\">U.S. Department of Energy \u2014 Solar Guide and Grid-Forming Inverter Guidance<\/a><\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"<p>To size an ATS for a hybrid solar inverter, first identify what the switch will actually transfer.&nbsp;Do not select it from PV-array kilowatts alone. At the installed point, compare the maximum grid pass-through current, the inverter&#8217;s maximum backup-output current, and the design current of the transferred-load panel. Use the highest current that can legitimately pass [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":2073,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-2063","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-electrical-guides"],"blocksy_meta":[],"_links":{"self":[{"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/posts\/2063","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/comments?post=2063"}],"version-history":[{"count":3,"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/posts\/2063\/revisions"}],"predecessor-version":[{"id":2074,"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/posts\/2063\/revisions\/2074"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/media\/2073"}],"wp:attachment":[{"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/media?parent=2063"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/categories?post=2063"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/tags?post=2063"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}