{"id":1855,"date":"2026-07-27T22:15:02","date_gmt":"2026-07-27T14:15:02","guid":{"rendered":"https:\/\/jutrion.com\/?p=1855"},"modified":"2026-07-27T22:25:59","modified_gmt":"2026-07-27T14:25:59","slug":"comment-selectionner-un-parafoudre-dc-pour-systeme-solaire-photovoltaique","status":"publish","type":"post","link":"https:\/\/jutrion.com\/fr\/how-to-select-dc-spd-solar-pv\/","title":{"rendered":"How to Select a DC SPD for Solar PV: Type, Sizing, and Standards"},"content":{"rendered":"<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/01-dc-spd-solar-pv-hero-1024x576.jpg\" alt=\"\" class=\"wp-image-1857\" srcset=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/01-dc-spd-solar-pv-hero-1024x576.jpg 1024w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/01-dc-spd-solar-pv-hero-300x169.jpg 300w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/01-dc-spd-solar-pv-hero-768x432.jpg 768w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/01-dc-spd-solar-pv-hero.jpg 1400w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"has-palette-color-9-color has-text-color has-link-color has-large-font-size wp-elements-1 wp-block-paragraph\"><strong>R\u00e9ponse rapide : comment sp\u00e9cifier un SPD DC pour un champ solaire<\/strong><\/p>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Choose a DC SPD by four inputs: the array&#8217;s maximum open-circuit voltage, its maximum short-circuit current, whether a lightning protection system is present, and the earthing arrangement. Size the maximum continuous operating voltage to&nbsp;<strong>Ucpv \u2265 1.2 \u00d7 the array&#8217;s maximum Voc<\/strong>&nbsp;(IEC 61643-32), choisissez&nbsp;<strong>Type 2<\/strong>&nbsp;pour les toitures ordinaires ou&nbsp;<strong>Type 1+2<\/strong>&nbsp;lorsque l\u2019exposition \u00e0 la foudre ou un LPS est pr\u00e9sent, et confirmez que le dispositif est homologu\u00e9 DC avec un sectionneur thermique int\u00e9gr\u00e9. Adaptez la classe de tension au syst\u00e8me : 600 V, 1000 V ou 1500 V.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">A DC surge protective device fails in a way an AC one never does. On a cold, clear morning a photovoltaic string sits at its highest voltage of the year, the array is live the instant the sun clears the horizon, and there is no alternating zero-crossing to help extinguish an internal arc. An SPD chosen against the nominal system voltage \u2014 &#8220;it&#8217;s a 1000 V system, so a 1000 V device is fine&#8221; \u2014 can sit permanently overstressed, drift into leakage, and trip its thermal disconnector months before its rated life. The number that protects the array is not the nominal voltage; it is the array&#8217;s real maximum open-circuit voltage plus a margin, and everything else in the specification follows from getting that one figure right.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Ce guide parcourt la s\u00e9lection c\u00f4t\u00e9 DC de la mani\u00e8re dont un constructeur de tableaux ou un sp\u00e9cificateur EPC proc\u00e8de r\u00e9ellement : \u00e9tablir les donn\u00e9es du champ, dimensionner la tension, choisir le type, fixer les caract\u00e9ristiques de protection, puis boucler sur le courant de d\u00e9faut, le sectionneur thermique, la configuration, la mise \u00e0 la terre, la fiche technique, le c\u00f4t\u00e9 AC et le cycle de vie. Il suit le cadre de l\u2019IEC 61643-31 (la norme produit pour les SPD DC photovolta\u00efques) et de l\u2019IEC 61643-32 (s\u00e9lection et application). Pour une vue plus large couvrant les dispositifs de Type 1, 2 et 3 et les c\u00f4t\u00e9s AC et DC, voir le&nbsp;<a href=\"https:\/\/jutrion.com\/fr\/guide-des-dispositifs-de-protection-contre-les-surtensions\/\">guide complet des dispositifs de protection contre les surtensions<\/a>; cet article est le compagnon c\u00f4t\u00e9 DC qui approfondit l\u00e0 o\u00f9 un champ solaire rend la d\u00e9cision diff\u00e9rente.<\/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\">Pourquoi un SPD DC n\u2019est pas un SPD AC tourn\u00e9 sur le c\u00f4t\u00e9<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">La tentation de r\u00e9utiliser un parafoudre AC de rechange c\u00f4t\u00e9 PV est le raccourci le plus dangereux de la protection contre les surtensions solaires. Le courant alternatif passe par z\u00e9ro cent fois par seconde ; lorsqu\u2019une varistance en fin de vie commence \u00e0 conduire, ce passage naturel par z\u00e9ro aide le sectionneur interne \u00e0 couper le courant de suite. Un champ photovolta\u00efque fournit un courant continu permanent sans aucun passage par z\u00e9ro. Une varistance \u00e0 oxyde m\u00e9tallique en d\u00e9gradation peut donc entretenir un arc DC, chauffer et devenir une source d\u2019incendie au lieu de tomber en panne de mani\u00e8re s\u00fbre.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">L\u2019\u00e9l\u00e9ment de protection lui-m\u00eame fonctionne de la m\u00eame mani\u00e8re dans les deux mondes : une varistance \u00e0 oxyde m\u00e9tallique (MOV) est en pratique un circuit ouvert \u00e0 la tension normale et s\u2019effondre \u00e0 une faible imp\u00e9dance en quelques nanosecondes lorsque la tension franchit son seuil, d\u00e9viant la surtension vers la terre et limitant la tension r\u00e9siduelle. Certains dispositifs associent la MOV \u00e0 un \u00e9clateur \u00e0 gaz (GDT) en s\u00e9rie pour \u00e9liminer le courant de fuite et am\u00e9liorer le mode de d\u00e9faillance. Ce qui change c\u00f4t\u00e9 DC n\u2019est pas la physique de l\u2019\u00e9cr\u00eatage mais le comportement en d\u00e9faut apr\u00e8s le vieillissement de l\u2019\u00e9l\u00e9ment, et c\u2019est pourquoi le dispositif entier \u2014 sa tension assign\u00e9e, son sectionneur et sa topologie interne \u2014 est con\u00e7u pour le DC.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Pour cette raison, un SPD DC photovolta\u00efque conforme est construit diff\u00e9remment. Il est homologu\u00e9 pour un fonctionnement continu en DC, ses modes de protection sont agenc\u00e9s pour un champ DC flottant ou fonctionnellement mis \u00e0 la terre plut\u00f4t que pour une alimentation AC r\u00e9f\u00e9renc\u00e9e au neutre, et il comporte un&nbsp;<strong>sectionneur thermique int\u00e9gr\u00e9<\/strong>&nbsp;L\u2019\u00e9l\u00e9ment de protection lui-m\u00eame fonctionne de la m\u00eame mani\u00e8re dans les deux mondes : une varistance \u00e0 oxyde m\u00e9tallique (MOV) est en pratique un circuit ouvert \u00e0 la tension normale et s\u2019effondre \u00e0 une faible imp\u00e9dance en quelques nanosecondes lorsque la tension franchit son seuil, d\u00e9rivant la surtension vers la terre et limitant la tension r\u00e9siduelle. Certains appareils associent la MOV \u00e0 un \u00e9clateur \u00e0 gaz (GDT) en s\u00e9rie pour \u00e9liminer le courant de fuite et am\u00e9liorer le mode de d\u00e9faillance. Ce qui change c\u00f4t\u00e9 continu, ce n\u2019est pas la physique de l\u2019\u00e9cr\u00eatage, mais le comportement en d\u00e9faut apr\u00e8s le vieillissement de l\u2019\u00e9l\u00e9ment, et c\u2019est pourquoi l\u2019appareil complet \u2014 son calibre de tension, son sectionneur et sa topologie interne \u2014 est con\u00e7u pour le continu.&nbsp;<a href=\"https:\/\/jutrion.com\/fr\/protecteur-contre-les-surtensions-et-sous-tensions\/\">C\u2019est pourquoi un parafoudre DC photovolta\u00efque conforme est construit diff\u00e9remment. Il est pr\u00e9vu pour un fonctionnement continu en courant continu, ses modes de protection sont agenc\u00e9s pour un champ photovolta\u00efque flottant ou fonctionnellement reli\u00e9 \u00e0 la terre plut\u00f4t que pour une alimentation alternative r\u00e9f\u00e9renc\u00e9e au neutre, et il comporte un<\/a>, sectionneur thermique int\u00e9gr\u00e9.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color wp-elements-3\">qui isole la varistance en cas de d\u00e9faillance sans d\u00e9pendre d\u2019un passage \u00e0 z\u00e9ro du courant. La norme IEC 61643-31 indique explicitement que ces appareils sont d\u00e9di\u00e9s au c\u00f4t\u00e9 continu des g\u00e9n\u00e9rateurs photovolta\u00efques et des onduleurs \u2014 un parafoudre AC ne satisfait pas \u00e0 ces exigences et ne doit jamais \u00eatre utilis\u00e9 en remplacement. Il s\u2019agit d\u2019un travail diff\u00e9rent de celui d\u2019un appareil qui prot\u00e8ge contre les surtensions et sous-tensions durables du r\u00e9seau ; si votre pr\u00e9occupation est une mont\u00e9e ou une baisse lente de la tension d\u2019alimentation plut\u00f4t qu\u2019un transitoire de l\u2019ordre de la microseconde, cela rel\u00e8ve du domaine d\u2019un<\/h3>\n<\/blockquote>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/02-solar-pv-dc-spd-selection-inputs-1024x576.jpg\" alt=\"\" class=\"wp-image-1858\" srcset=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/02-solar-pv-dc-spd-selection-inputs-1024x576.jpg 1024w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/02-solar-pv-dc-spd-selection-inputs-300x169.jpg 300w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/02-solar-pv-dc-spd-selection-inputs-768x432.jpg 768w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/02-solar-pv-dc-spd-selection-inputs.jpg 1400w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">protecteur contre les surtensions et sous-tensions<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>, et non d\u2019un parafoudre.<\/strong>&nbsp;Commencez par le champ photovolta\u00efque : les quatre donn\u00e9es qui d\u00e9terminent le parafoudre.<\/li>\n\n\n\n<li><strong>Chaque caract\u00e9ristique de la fiche technique du parafoudre r\u00e9pond \u00e0 une question sur le champ photovolta\u00efque. \u00c9tablissez ces quatre donn\u00e9es avant de consulter un quelconque produit :.<\/strong>&nbsp;The array&#8217;s prospective short-circuit current at the SPD&#8217;s position, enhanced for irradiance and temperature. This sets the short-circuit withstand requirement and decides whether an external backup device is needed.<\/li>\n\n\n\n<li><strong>Pas la tension nominale du syst\u00e8me \u2014 la tension la plus \u00e9lev\u00e9e que la cha\u00eene peut atteindre, qui survient en circuit ouvert le matin le plus froid attendu. Cela d\u00e9termine Ucpv.<\/strong>&nbsp;Courant de court-circuit maximal, Iscpv.<\/li>\n\n\n\n<li><strong>Le courant de court-circuit pr\u00e9sum\u00e9 du champ photovolta\u00efque \u00e0 l\u2019emplacement du parafoudre, major\u00e9 pour l\u2019irradiance et la temp\u00e9rature. Cela d\u00e9termine l\u2019exigence de tenue au court-circuit et d\u00e9cide si un dispositif de secours externe est n\u00e9cessaire.<\/strong>&nbsp;Functionally earthed or floating array, and the cable distance between array and inverter. This decides the SPD&#8217;s internal configuration and how many SPD locations the system needs.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Si le site poss\u00e8de un syst\u00e8me de protection contre la foudre, se trouve dans un endroit expos\u00e9 ou \u00e0 forte densit\u00e9 de foudroiement, ou ne peut pas maintenir la distance de s\u00e9paration par rapport aux conducteurs de descente. Cela d\u00e9cide entre Type 2 et Type 1+2.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color wp-elements-4\">R\u00e9gime de neutre et longueur des c\u00e2bles DC.<\/h3>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Champ photovolta\u00efque fonctionnellement reli\u00e9 \u00e0 la terre ou flottant, et distance de c\u00e2ble entre le champ et l\u2019onduleur. Cela d\u00e9cide de la configuration interne du parafoudre et du nombre d\u2019emplacements de parafoudres n\u00e9cessaires au syst\u00e8me.<\/strong>&nbsp;is the maximum continuous operating voltage the SPD can withstand indefinitely without degrading. Every mode of protection inside the device \u2014 positive-to-earth, negative-to-earth, and pole-to-pole \u2014 must ride above the array&#8217;s highest voltage under all service conditions. IEC 61643-32 states the rule directly:<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Dimensionnement de Ucpv : la r\u00e8gle du 1,2 \u00d7 Voc et la v\u00e9rification du matin froid<\/strong>, where Uoc(max) is the array&#8217;s maximum open-circuit voltage at standard test conditions.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">est la tension de service continu maximale que le parafoudre peut supporter ind\u00e9finiment sans se d\u00e9grader. Chaque mode de protection \u00e0 l\u2019int\u00e9rieur de l\u2019appareil \u2014 positif-terre, n\u00e9gatif-terre et p\u00f4le-p\u00f4le \u2014 doit rester au-dessus de la tension la plus \u00e9lev\u00e9e du champ photovolta\u00efque dans toutes les conditions de service. La norme IEC 61643-32 \u00e9nonce directement la r\u00e8gle :.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color wp-elements-5\">Ucpv \u2265 1,2 \u00d7 Uoc(max)<\/h3>\n<\/blockquote>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/03-ucpv-sizing-example-1024x576.jpg\" alt=\"\" class=\"wp-image-1859\" srcset=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/03-ucpv-sizing-example-1024x576.jpg 1024w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/03-ucpv-sizing-example-300x169.jpg 300w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/03-ucpv-sizing-example-768x432.jpg 768w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/03-ucpv-sizing-example.jpg 1400w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">, o\u00f9 Uoc(max) est la tension maximale en circuit ouvert du champ photovolta\u00efque dans les conditions d\u2019essai normalis\u00e9es.<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li>Le facteur 1,2 n\u2019est pas une marge arbitraire. La tension en circuit ouvert augmente lorsque la temp\u00e9rature des cellules descend sous les 25 \u00b0C des conditions d\u2019essai normalis\u00e9es, d\u2019environ 0,3 % par degr\u00e9 pour le silicium cristallin. La marge de 20 % absorbe cette hausse par temps froid dans la plupart des climats, de sorte que le parafoudre n\u2019est jamais exploit\u00e9 \u00e0 sa valeur Ucpv ou au-dessus lorsque le champ photovolta\u00efque atteint son maximum \u00e0 l\u2019aube.&nbsp;<strong>Exemple concret : une cha\u00eene de classe 1500 V<\/strong>.<\/li>\n\n\n\n<li>Prenons une cha\u00eene de 24 modules, chacun ayant une tension en circuit ouvert STC de 49,5 V.&nbsp;<strong>Uoc(max) du champ photovolta\u00efque aux STC = 24 \u00d7 49,5 V =<\/strong>.<\/li>\n\n\n\n<li>1188 V&nbsp;<strong>Appliquez la marge normalis\u00e9e : Ucpv \u2265 1,2 \u00d7 1188 V =<\/strong>&nbsp;1426 V.<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\">Choisissez la classe de tension imm\u00e9diatement sup\u00e9rieure \u00e0 ce chiffre : un&nbsp;<strong>parafoudre DC 1500 V<\/strong>&nbsp;\u2014 still comfortably below the 1500 V Ucpv. For a very cold climate, compute Voc at your own design minimum temperature with the module&#8217;s temperature coefficient and confirm Ucpv still clears it; the 1.2 factor covers ordinary conditions, not an Arctic install. Then map to the class shortlist:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>V\u00e9rifiez le matin froid pour un site extr\u00eame. \u00c0 une temp\u00e9rature minimale de conception des cellules de \u221210 \u00b0C, le terme de temp\u00e9rature est une baisse de 35 degr\u00e9s \u00d7 0,3 %\/\u00b0C \u2248 +10,5 %, donc Voc monte \u00e0 environ 1188 \u00d7 1,105 \u2248.<\/li>\n\n\n\n<li>1313 V.<\/li>\n\n\n\n<li>Syst\u00e8mes 1500 V \u2192 classe 1500 V.<\/li>\n<\/ul>\n\n\n\n<blockquote class=\"wp-block-quote has-palette-color-9-color has-text-color has-link-color wp-elements-6 is-layout-flow wp-block-quote-is-layout-flow\">\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color wp-elements-7\">Type 2 ou Type 1+2 ? Adaptez le parafoudre \u00e0 l\u2019exposition \u00e0 la foudre<\/h3>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">The type is a lightning-risk decision, not a quality tier. It follows from the fourth input above and from the site&#8217;s lightning protection design.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Type 2<\/strong>&nbsp;les appareils sont test\u00e9s avec l\u2019onde 8\/20 \u00b5s et caract\u00e9ris\u00e9s par le courant nominal de d\u00e9charge (In) et le courant maximal de d\u00e9charge (Imax). Ils traitent les surtensions induites et les transitoires de commutation \u2014 la menace quotidienne sur une toiture de b\u00e2timent sans syst\u00e8me de protection externe contre la foudre. Cela couvre la majorit\u00e9 des installations photovolta\u00efques r\u00e9sidentielles et commerciales en toiture.<\/li>\n\n\n\n<li><strong>Type 1+2<\/strong>&nbsp;les appareils ajoutent une tenue au courant partiel de foudre, le courant impulsionnel Iimp test\u00e9 avec l\u2019onde 10\/350 \u00b5s, tout en assurant une protection de Type 2. Sp\u00e9cifiez-les lorsqu\u2019un syst\u00e8me de protection contre la foudre est pr\u00e9sent et que la distance de s\u00e9paration ne peut pas \u00eatre maintenue, sur les installations au sol expos\u00e9es et en sommet de colline, et dans les r\u00e9gions \u00e0 forte densit\u00e9 de foudroiement \u2014 partout o\u00f9 une part du courant direct de foudre peut \u00eatre conduite vers le c\u00f4t\u00e9 DC.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The deciding question is whether direct or partial lightning current can reach the array wiring, which is assessed through the site&#8217;s lightning protection risk analysis (the IEC 62305 series). If the answer is yes, the extra Iimp capability of a Type 1+2 device is protecting against an energy the Type 2 test does not represent. If the answer is clearly no, a well-specified Type 2 device is the correct and more economical choice, not a compromise.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote has-palette-color-9-color has-text-color has-link-color wp-elements-8 is-layout-flow wp-block-quote-is-layout-flow\">\n<h3 class=\"wp-block-heading has-palette-color-9-color has-text-color has-link-color wp-elements-9\">Les caract\u00e9ristiques c\u00f4t\u00e9 DC qui prot\u00e8gent r\u00e9ellement l\u2019onduleur<\/h3>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Une fois la tension et le type fix\u00e9s, trois caract\u00e9ristiques d\u00e9terminent si l\u2019onduleur derri\u00e8re le parafoudre est r\u00e9ellement prot\u00e9g\u00e9 :<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th class=\"has-text-align-left\" data-align=\"left\">Caract\u00e9ristique<\/th><th class=\"has-text-align-left\" data-align=\"left\">Ce qu\u2019elle repr\u00e9sente<\/th><th class=\"has-text-align-left\" data-align=\"left\">R\u00e8gle de s\u00e9lection<\/th><\/tr><\/thead><tbody><tr><td class=\"has-text-align-left\" data-align=\"left\"><strong>En haut<\/strong>&nbsp;(niveau de protection en tension)<\/td><td class=\"has-text-align-left\" data-align=\"left\">La tension r\u00e9siduelle que le parafoudre laisse atteindre l\u2019\u00e9quipement pendant une surtension<\/td><td class=\"has-text-align-left\" data-align=\"left\">Keep Up at least ~20&nbsp;% below the impulse withstand voltage (Uw) of the inverter&#8217;s DC input, so a margin remains after lead-length losses<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\"><strong>Dans<\/strong>&nbsp;(courant nominal de d\u00e9charge)<\/td><td class=\"has-text-align-left\" data-align=\"left\">Le courant 8\/20 \u00b5s que le parafoudre peut d\u00e9river de fa\u00e7on r\u00e9p\u00e9t\u00e9e sans dommage<\/td><td class=\"has-text-align-left\" data-align=\"left\">Un In plus \u00e9lev\u00e9 donne plus de r\u00e9serve et une dur\u00e9e de vie plus longue sur les sites expos\u00e9s ; traitez-le comme la caract\u00e9ristique de travail, pas comme le maximum<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\"><strong>Imax<\/strong>&nbsp;(courant maximal de d\u00e9charge)<\/td><td class=\"has-text-align-left\" data-align=\"left\">Le courant 8\/20 \u00b5s d\u2019un seul \u00e9v\u00e9nement que le parafoudre peut supporter une fois<\/td><td class=\"has-text-align-left\" data-align=\"left\">Un plafond de survie pour un \u00e9v\u00e9nement s\u00e9v\u00e8re, pas une valeur de service ; sp\u00e9cifiez avec une marge au-dessus de la surtension attendue, pas \u00e9gale \u00e0 celle-ci<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Up is the rating that most often gets ignored and most directly decides whether the inverter survives. A device with an impressive Imax but a Up that sits close to the inverter&#8217;s withstand voltage lets through a transient the electronics cannot absorb. The JUTRION solar DC range, for example, specifies Up on its 40 kA (8\/20&nbsp;\u00b5s Imax) devices so this coordination can be checked against the inverter datasheet rather than assumed.<\/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 wp-elements-10\">Coordinate the stages, and check the inverter&#8217;s built-in SPD<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Deux questions li\u00e9es aux parafoudres d\u00e9terminent si des appareils suppl\u00e9mentaires aident ou gaspillent simplement de l\u2019argent.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Coordination \u00e9nerg\u00e9tique entre les \u00e9tages.<\/strong>&nbsp;When a Type 1+2 device at the array or combiner box works together with a Type 2 device at the inverter, the two must be energy-coordinated so the upstream device takes the high-energy hit and the downstream device only trims the residual. Coordination is achieved by keeping enough DC cable between the stages \u2014 roughly 10 metres provides sufficient inductive decoupling \u2014 or, where that distance is not available, by a decoupling inductor or a manufacturer-verified coordinated set. Mixing two makers&#8217; devices with no defined decoupling can leave the downstream SPD overstressed; follow the manufacturer&#8217;s coordination data rather than assuming any two devices cooperate.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>L\u2019onduleur peut d\u00e9j\u00e0 contenir un SPD DC.<\/strong>&nbsp;De nombreux onduleurs string modernes sont livr\u00e9s avec un SPD DC de Type 2 int\u00e9gr\u00e9 ou un emplacement pour un module enfichable. Confirmez ce point avant de sp\u00e9cifier un dispositif externe \u00e0 l\u2019entr\u00e9e DC de l\u2019onduleur : si l\u2019onduleur prot\u00e8ge d\u00e9j\u00e0 ses propres bornes, l\u2019effort externe appartient au niveau du champ ou du coffret de regroupement, l\u00e0 o\u00f9 un long c\u00e2ble DC direct est sinon non prot\u00e9g\u00e9. Sp\u00e9cifier un second SPD \u00e0 200 mm d\u2019un dispositif int\u00e9gr\u00e9 existant ne prot\u00e8ge rien de nouveau et ajoute un point de d\u00e9faillance.<\/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 wp-elements-11\">Courant de d\u00e9faut, protection de secours et sectionneur thermique : la cha\u00eene de s\u00e9curit\u00e9 que les concurrents ignorent<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">C\u2019est ici qu\u2019une s\u00e9lection de qualit\u00e9 se distingue d\u2019un choix de catalogue, et c\u2019est l\u00e0 que la plupart des articles sur les SPD solaires restent silencieux. Trois exigences li\u00e9es emp\u00eachent un SPD d\u00e9faillant de devenir un d\u00e9faut DC.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-medium-font-size\">Tenue au court-circuit (Iscpv \/ SCCR)<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The SPD must survive the array&#8217;s prospective short-circuit current at its installed position. Compare the device&#8217;s rated short-circuit withstand current, Iscpv, against the array&#8217;s maximum short-circuit current \u2014 approximately 1.25 \u00d7 the modules&#8217; STC Isc for the relevant number of parallel strings, the 1.25 factor covering irradiance and temperature enhancement per PV array design practice (IEC 62548). For a combiner box gathering four parallel strings of modules rated 13.5 A STC short-circuit current, that is 1.25 \u00d7 13.5 A \u00d7 4 \u2248&nbsp;<strong>68 A<\/strong>; the SPD at that position needs an Iscpv rating at or above roughly 68 A. The SPD&#8217;s Iscpv must be equal to or greater than that figure at every location where it is installed.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-medium-font-size\">Le sectionneur thermique int\u00e9gr\u00e9<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Comme un arc DC n\u2019a pas de passage naturel par z\u00e9ro du courant, la norme IEC 61643-31 exige que le SPD s\u2019isole lui-m\u00eame en cas de d\u00e9faillance. En pratique, il s\u2019agit d\u2019un&nbsp;<strong>sectionneur thermique<\/strong>&nbsp;li\u00e9 \u00e0 la varistance qui ouvre le chemin de protection lorsque l\u2019\u00e9l\u00e9ment surchauffe en fin de vie. C\u2019est un \u00e9l\u00e9ment de s\u00e9curit\u00e9 obligatoire d\u2019un SPD DC PV, pas une fonction haut de gamme \u2014 un dispositif qui en est d\u00e9pourvu n\u2019a pas sa place du c\u00f4t\u00e9 DC.<\/p>\n\n\n\n<h3 class=\"wp-block-heading has-medium-font-size\">Lorsqu\u2019un dispositif de secours externe est n\u00e9cessaire<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">An external backup fuse or DC-rated disconnector is required only when the array&#8217;s prospective short-circuit current&nbsp;<em>d\u00e9passe<\/em>&nbsp;the SPD&#8217;s Iscpv rating. Many PV DC SPDs are rated to withstand the full string short-circuit current and need no external backup at all; adding an unnecessary fuse only introduces an extra failure point and lead length. Read the SPD datasheet: it states the maximum array short-circuit current the device tolerates unaided and, where a backup is needed, the recommended rating. On larger plants, also specify a device with a&nbsp;<strong>contact de signalisation \u00e0 distance<\/strong>&nbsp;afin qu\u2019un op\u00e9rateur voie un SPD en fin de vie sur le syst\u00e8me de surveillance au lieu d\u2019ouvrir les armoires pour v\u00e9rifier les indicateurs d\u2019\u00e9tat.<\/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 wp-elements-12\">Configuration de c\u00e2blage : 2 p\u00f4les standard ou Y pour les champs mis \u00e0 la terre et flottants<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">PV DC SPDs come in more than one internal topology, and the choice depends on the array&#8217;s earthing arrangement. The two you will meet are:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Bipolaire standard :<\/strong>&nbsp;une varistance entre le p\u00f4le positif et la terre et une autre entre le p\u00f4le n\u00e9gatif et la terre. Simple et adapt\u00e9e aux syst\u00e8mes mis \u00e0 la terre fonctionnellement lorsque cette configuration convient au g\u00e9n\u00e9rateur.<\/li>\n\n\n\n<li><strong>Configuration en Y (\u00e9galement appel\u00e9e 3+0 ou protection totale) :<\/strong>&nbsp;les p\u00f4les positif et n\u00e9gatif se connectent chacun via une varistance \u00e0 un n\u0153ud commun, et ce n\u0153ud est reli\u00e9 \u00e0 la terre via un \u00e9clateur \u00e0 gaz (parafoudre \u00e0 \u00e9clateur). Comme l\u2019\u00e9clateur bloque le courant continu permanent vers la terre, une seule varistance d\u00e9faillante ne peut pas cr\u00e9er de d\u00e9faut permanent p\u00f4le-terre, et cette configuration convient aussi bien aux installations flottantes (non reli\u00e9es \u00e0 la terre) qu\u2019aux installations fonctionnellement reli\u00e9es \u00e0 la terre. C\u2019est la configuration utilis\u00e9e par la plupart des parafoudres DC photovolta\u00efques pr\u00e9cis\u00e9ment pour cette raison.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Match the configuration to the array&#8217;s earthing arrangement and confirm it against the SPD datasheet; a device chosen only on voltage and current but wired in the wrong topology can leave a mode of protection ineffective or introduce leakage.<\/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 wp-elements-13\">Mise \u00e0 la terre, liaison \u00e9quipotentielle et dimensionnement des conducteurs<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">An SPD is only as good as the earth path it discharges into. The surge current the device diverts has to reach the mass of earth through a low-impedance route, and if that route is long, thin, or loosely terminated, the let-through voltage rises no matter how good the device&#8217;s Up is.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Section des conducteurs.<\/strong>&nbsp;Size the SPD&#8217;s connecting and earthing conductors for the surge, not just the working current. Common installation practice (IEC 60364-5-53) is at least 6&nbsp;mm\u00b2 copper for a Type 2 device and at least 16&nbsp;mm\u00b2 copper for a Type 1 or Type 1+2 device that carries partial lightning current. Confirm the figure against local wiring rules and the SPD instructions.<\/li>\n\n\n\n<li><strong>Liaison \u00e9quipotentielle.<\/strong>&nbsp;Bond the SPD&#8217;s earth terminal to the array frame earthing and the main earthing system so that, during a surge, the whole installation rises and falls together and no dangerous potential difference appears across the inverter. On systems with a lightning protection system, this bonding is part of the LPS earthing design, not a separate afterthought.<\/li>\n\n\n\n<li><strong>Raccordements.<\/strong>&nbsp;Maintenez les raccordements bien serr\u00e9s et prot\u00e9g\u00e9s contre la corrosion dans un coffret de regroupement ext\u00e9rieur ; un joint \u00e0 r\u00e9sistance \u00e9lev\u00e9e dans le chemin de terre neutralise discr\u00e8tement l\u2019appareil.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">La mise \u00e0 la terre est la partie de la sp\u00e9cification qu\u2019une fiche technique ne peut pas r\u00e9gler \u00e0 votre place. Deux parafoudres identiques, l\u2019un avec une terre \u00e9quipotentielle courte en 16 mm\u00b2 et l\u2019autre avec une queue longue et sous-dimensionn\u00e9e, prot\u00e8gent l\u2019onduleur de mani\u00e8re tr\u00e8s diff\u00e9rente.<\/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 wp-elements-14\">O\u00f9 installer, et les deux r\u00e8gles qui d\u00e9terminent la tension r\u00e9siduelle<\/h2>\n<\/blockquote>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/04-solar-pv-spd-installation-diagram-1024x576.jpg\" alt=\"\" class=\"wp-image-1860\" srcset=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/04-solar-pv-spd-installation-diagram-1024x576.jpg 1024w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/04-solar-pv-spd-installation-diagram-300x169.jpg 300w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/04-solar-pv-spd-installation-diagram-768x432.jpg 768w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/04-solar-pv-spd-installation-diagram.jpg 1400w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Un parafoudre ne prot\u00e8ge que ce qui se trouve \u00e0 proximit\u00e9 imm\u00e9diate, donc l\u2019emplacement fait partie de la sp\u00e9cification, et non d\u2019un ajout apr\u00e8s coup.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>\u00c0 l\u2019entr\u00e9e DC de l\u2019onduleur<\/strong>&nbsp;\u2014 sauf si l\u2019onduleur contient d\u00e9j\u00e0 un parafoudre DC coordonn\u00e9. C\u2019est l\u2019\u00e9quipement que vous prot\u00e9gez.<\/li>\n\n\n\n<li><strong>Au niveau du g\u00e9n\u00e9rateur ou du coffret de regroupement<\/strong>&nbsp;\u2014 lorsque le c\u00e2ble DC entre le g\u00e9n\u00e9rateur et l\u2019onduleur d\u00e9passe environ 10 m\u00e8tres. Au-del\u00e0 de cette distance, une surtension induite sur le long c\u00e2ble DC peut atteindre une tension suffisante pour qu\u2019un seul parafoudre \u00e0 l\u2019extr\u00e9mit\u00e9 \u00e9loign\u00e9e ne prot\u00e8ge plus les deux extr\u00e9mit\u00e9s ; il faut donc prot\u00e9ger aux deux.<\/li>\n\n\n\n<li><strong>Aux coffrets de regroupement et de regroupement secondaire<\/strong>&nbsp;\u2014 on multi-string and large ground-mount systems, one SPD per string group plus the DC disconnect, following the array&#8217;s protection zones.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Deux r\u00e8gles d\u2019installation d\u00e9terminent ensuite la tension qui atteint r\u00e9ellement l\u2019\u00e9quipement :<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>La r\u00e8gle des 0,5 m.<\/strong>&nbsp;Keep the total connecting-lead length \u2014 the loop through the live poles and the earth conductor \u2014 to about 0.5 m. Every extra length of lead adds inductive voltage (V = L \u00d7 di\/dt) on top of the device&#8217;s Up during a fast surge, so neat cabling routed the long way round the enclosure quietly raises the let-through voltage. Take the shortest path to the busbar and the earth bar.<\/li>\n\n\n\n<li><strong>Raccordez la terre en premier.<\/strong>&nbsp;\u00c9tablissez le chemin de terre de protection avant les conducteurs actifs afin que le chemin de d\u00e9charge existe d\u00e8s que le parafoudre est sous tension.<\/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 wp-elements-15\">Lisez la fiche technique : un d\u00e9codeur des param\u00e8tres d\u2019un SPD DC photovolta\u00efque<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Une sp\u00e9cification n\u2019est s\u00fbre qu\u2019une fois que vous savez lire la fiche technique sans deviner. Voici les lignes qui comptent sur un SPD DC photovolta\u00efque, et ce que chacune vous indique.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th class=\"has-text-align-left\" data-align=\"left\">Ligne de la fiche technique<\/th><th class=\"has-text-align-left\" data-align=\"left\">Ce qu\u2019elle signifie<\/th><th class=\"has-text-align-left\" data-align=\"left\">Ce qu\u2019il faut v\u00e9rifier<\/th><\/tr><\/thead><tbody><tr><td class=\"has-text-align-left\" data-align=\"left\">Ucpv (Uc DC)<\/td><td class=\"has-text-align-left\" data-align=\"left\">Tension de service continue maximale en DC<\/td><td class=\"has-text-align-left\" data-align=\"left\">\u2265 1,2 \u00d7 Voc maximal du champ, par mode de protection<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\">Type \/ Classe<\/td><td class=\"has-text-align-left\" data-align=\"left\">Type 2 (Classe II) ou Type 1+2 (Classe I+II)<\/td><td class=\"has-text-align-left\" data-align=\"left\">Correspond \u00e0 la d\u00e9cision d\u2019exposition \u00e0 la foudre<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\">Iimp (10\/350 \u00b5s)<\/td><td class=\"has-text-align-left\" data-align=\"left\">Courant impulsionnel partiel de foudre, essai Type 1<\/td><td class=\"has-text-align-left\" data-align=\"left\">Pr\u00e9sent et ad\u00e9quat uniquement l\u00e0 o\u00f9 le Type 1+2 est requis<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\">In (8\/20 \u00b5s)<\/td><td class=\"has-text-align-left\" data-align=\"left\">Courant nominal de d\u00e9charge, service r\u00e9p\u00e9t\u00e9<\/td><td class=\"has-text-align-left\" data-align=\"left\">Dimensionn\u00e9 selon l\u2019exposition du site ; la valeur de service<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\">Imax (8\/20 \u00b5s)<\/td><td class=\"has-text-align-left\" data-align=\"left\">Courant maximal de d\u00e9charge unique<\/td><td class=\"has-text-align-left\" data-align=\"left\">Marge confortable au-dessus de la surtension attendue<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\">En haut<\/td><td class=\"has-text-align-left\" data-align=\"left\">Niveau de protection en tension (tension r\u00e9siduelle)<\/td><td class=\"has-text-align-left\" data-align=\"left\">\u2265 20 % en dessous de la tension de tenue DC de l\u2019onduleur<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\">Iscpv \/ SCCR<\/td><td class=\"has-text-align-left\" data-align=\"left\">Tenue au court-circuit aux bornes<\/td><td class=\"has-text-align-left\" data-align=\"left\">\u2265 courant de court-circuit maximal du champ \u00e0 cet endroit<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\">Temps de r\u00e9ponse (tA)<\/td><td class=\"has-text-align-left\" data-align=\"left\">\u00c0 quelle vitesse l'\u00e9l\u00e9ment se serre<\/td><td class=\"has-text-align-left\" data-align=\"left\">Ordre de la nanoseconde pour les dispositifs \u00e0 base de MOV<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\">D\u00e9connecteur thermique \/ indicateur<\/td><td class=\"has-text-align-left\" data-align=\"left\">S\u00e9curit\u00e9 int\u00e9gr\u00e9e interne et fen\u00eatre d'\u00e9tat<\/td><td class=\"has-text-align-left\" data-align=\"left\">Pr\u00e9sent ; indication vert\/rouge ou drapeau ; module enfichable pr\u00e9f\u00e9r\u00e9<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\">Contact de signalisation \u00e0 distance<\/td><td class=\"has-text-align-left\" data-align=\"left\">Contact libre de potentiel pour la surveillance<\/td><td class=\"has-text-align-left\" data-align=\"left\">\u00c0 sp\u00e9cifier sur les grandes installations ou celles sans surveillance<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\">Temp\u00e9rature de fonctionnement \/ IP<\/td><td class=\"has-text-align-left\" data-align=\"left\">Plage environnementale et indice de protection<\/td><td class=\"has-text-align-left\" data-align=\"left\">Adapt\u00e9 au climat et \u00e0 l'enveloppe du coffret de regroupement<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\">P\u00f4les \/ montage \/ bornes<\/td><td class=\"has-text-align-left\" data-align=\"left\">2 p\u00f4les ou Y, rail DIN 35 mm, capacit\u00e9 des conducteurs<\/td><td class=\"has-text-align-left\" data-align=\"left\">Correspond au r\u00e9gime de neutre et \u00e0 la section des c\u00e2bles<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Si l'une de ces lignes manque dans une fiche technique \u2014 en particulier Ucpv, Iscpv ou le d\u00e9connecteur thermique \u2014 traitez cette omission comme une raison de poser la question, pas comme une hypoth\u00e8se \u00e0 faire. Un dispositif qui ne pr\u00e9cise pas sa tenue au court-circuit ou sa tension nominale DC n'est pas document\u00e9 pour le c\u00f4t\u00e9 DC.<\/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 wp-elements-16\">Don&#8217;t forget the AC side: protecting the whole PV system<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">A PV surge-protection specification that stops at the DC side is only half a specification. The same lightning or switching event that threatens the array reaches the inverter&#8217;s AC output and the point of connection to the building or grid, and that side needs its own SPD to IEC 61643-11 \u2014 an&nbsp;<em>CA<\/em>&nbsp;dispositif, dimensionn\u00e9 selon la tension du syst\u00e8me AC (par exemple Uc autour de 275 V phase-terre sur un syst\u00e8me 230\/400 V), et non un dispositif DC.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Coordinate the two sides: a Type 2 AC SPD at the inverter output and main AC board for a building with no external LPS, or a Type 1+2 AC SPD at the origin where an LPS is present, mirroring the logic used on the DC side. JUTRION&#8217;s AC range \u2014 the JUSPD-40AC (Type 2) and JUSPD-12.5AC (Type 1+2) \u2014 covers this side to the same standards, so a single supplier can provide a coordinated DC-and-AC set rather than two unmatched halves.<\/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 wp-elements-17\">Surveillance, maintenance et remplacement<\/h2>\n<\/blockquote>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/05-dc-spd-maintenance-features-1024x576.jpg\" alt=\"\" class=\"wp-image-1861\" srcset=\"https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/05-dc-spd-maintenance-features-1024x576.jpg 1024w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/05-dc-spd-maintenance-features-300x169.jpg 300w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/05-dc-spd-maintenance-features-768x432.jpg 768w, https:\/\/jutrion.com\/wp-content\/uploads\/2026\/07\/05-dc-spd-maintenance-features.jpg 1400w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">An SPD is a wear part. Every surge it diverts consumes a little of the varistor&#8217;s life, and the device is designed to reach end of life and disconnect rather than fail catastrophically. Specifying for that lifecycle is part of selection, not a separate maintenance topic.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Modules enfichables.<\/strong>&nbsp;Pr\u00e9f\u00e9rez un dispositif avec un module de protection enfichable et une embase qui reste c\u00e2bl\u00e9e. Le remplacement ne prend alors que quelques secondes et ne perturbe pas les terminaisons DC ni le chemin de terre \u2014 important sur un syst\u00e8me photovolta\u00efque sous tension qui ne peut pas simplement \u00eatre \u00e9teint en plein jour.<\/li>\n\n\n\n<li><strong>Indication d'\u00e9tat.<\/strong>&nbsp;Un drapeau m\u00e9canique ou une fen\u00eatre vert-rouge montre en un coup d'\u0153il si le module prot\u00e8ge encore. Sur un grand champ ou un champ en toiture o\u00f9 personne n'inspecte le coffret de regroupement chaque semaine, ajoutez le contact de signalisation \u00e0 distance et c\u00e2blez-le au syst\u00e8me de surveillance afin qu'un module en fin de vie d\u00e9clenche une alarme.<\/li>\n\n\n\n<li><strong>Inspection et remplacement.<\/strong>&nbsp;Check the indicators at each scheduled maintenance visit and after any known severe lightning event in the area. When the window shows red or the module has disconnected, replace the module \u2014 it no longer protects, even though the array keeps generating. Isolate safely and follow the manufacturer&#8217;s live-working guidance before removing a module on an energised DC system.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Designing the array&#8217;s protection so a failed module can be seen and swapped quickly is what keeps the protection real years after commissioning, rather than a green light everyone assumes is still green.<\/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 wp-elements-18\">Exemple concret : une toiture commerciale de 100 kW<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">La m\u00e9thode se rassemble sur un seul projet r\u00e9aliste. Ce cas est illustratif, pas une installation JUTRION sp\u00e9cifique, mais l'arithm\u00e9tique est l'arithm\u00e9tique que vous feriez r\u00e9ellement.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Le syst\u00e8me.<\/strong>&nbsp;Un toit commercial plat de 100 kWc, onduleurs string 1500 V, aucun syst\u00e8me de protection externe contre la foudre sur le b\u00e2timent, densit\u00e9 de foudroiement mod\u00e9r\u00e9e. Modules : 550 W, Voc(STC) 49,9 V, Isc(STC) 13,85 A, coefficient de temp\u00e9rature de Voc environ \u22120,28 %\/\u00b0C. Cha\u00eenes de 24 modules, quatre cha\u00eenes par coffret de regroupement, coffrets de regroupement \u00e0 environ 15 m de c\u00e2ble des onduleurs.<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Tension.<\/strong>&nbsp;Voc(STC) de cha\u00eene = 24 \u00d7 49,9 = 1197,6 V. Ucpv \u2265 1,2 \u00d7 1197,6 =&nbsp;<strong>1437 V<\/strong>&nbsp;\u2192 un dispositif de&nbsp;<strong>classe 1500 V<\/strong>&nbsp;V\u00e9rification \u00e0 froid \u00e0 un minimum de conception de \u22125 \u00b0C : +8,4 % sur Voc \u2248 1298 V, toujours sous 1500 V. La longueur de cha\u00eene est s\u00fbre pour un syst\u00e8me 1500 V ; une cha\u00eene de 26 modules aurait pouss\u00e9 Ucpv \u00e0 ~1560 V et hors de la classe 1500 V.<\/li>\n\n\n\n<li><strong>Type.<\/strong>&nbsp;Pas de parafoudre externe et un toit de b\u00e2timent \u2192&nbsp;<strong>Type 2<\/strong>&nbsp;est correct \u00e0 la fois c\u00f4t\u00e9 coffret de regroupement et c\u00f4t\u00e9 onduleur. Un Type 1+2 ne serait sp\u00e9cifi\u00e9 que si un parafoudre \u00e9tait ajout\u00e9 ou si le site \u00e9tait fortement expos\u00e9.<\/li>\n\n\n\n<li><strong>Tenue au court-circuit.<\/strong>&nbsp;Par coffret, quatre cha\u00eenes en parall\u00e8le : Iscpv \u2265 1,25 \u00d7 13,85 \u00d7 4 \u2248&nbsp;<strong>69 A<\/strong>. Choisir un dispositif dont l\u2019Iscpv d\u00e9passe 69 A ; la plupart le feront, donc aucun fusible de secours externe n\u2019est n\u00e9cessaire \u2014 \u00e0 confirmer sur la fiche technique.<\/li>\n\n\n\n<li><strong>Emplacements et coordination.<\/strong>&nbsp;Le trajet de 15 m d\u00e9passe 10 m, donc prot\u00e9ger&nbsp;<strong>les deux<\/strong>&nbsp;coffrets de regroupement et l\u2019entr\u00e9e DC de l\u2019onduleur ; les 15 m de c\u00e2ble fournissent aussi le d\u00e9couplage qui maintient la coordination \u00e9nerg\u00e9tique des deux \u00e9tages. V\u00e9rifier d\u2019abord si les onduleurs contiennent d\u00e9j\u00e0 un SPD DC int\u00e9gr\u00e9 \u2014 si c\u2019est le cas, conserver les dispositifs des coffrets de regroupement et omettre ceux redondants \u00e0 l\u2019entr\u00e9e de l\u2019onduleur.<\/li>\n\n\n\n<li><strong>Up et mise \u00e0 la terre.<\/strong>&nbsp;Confirm each device&#8217;s Up sits at least 20&nbsp;% below the inverter&#8217;s DC withstand voltage, and earth each SPD with at least 6&nbsp;mm\u00b2 copper bonded to the array frame and main earth.<\/li>\n\n\n\n<li><strong>AC side.<\/strong>&nbsp;Add a Type 2 AC SPD at the inverter AC output \/ main LV board, Uc about 275&nbsp;V, to IEC 61643-11.<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Result:<\/strong>&nbsp;Type 2, 1500&nbsp;V-class DC SPDs with Iscpv \u2265 ~70&nbsp;A at each combiner box and (if the inverter has no integrated device) at each inverter DC input, remote signaling on the combiner units for roof-level monitoring, plus a Type 2 AC SPD at the AC board. That is a coordinated, documented specification \u2014 not a box picked on discharge current 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 wp-elements-19\">Selection matrix: from PV system to a specified DC SPD<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">The matrix below turns the four inputs into a first-pass specification. Read across from the system and its exposure to the type, voltage class, discharge rating, and where the device belongs. Confirm the exact figures against the array calculation and the SPD datasheet before ordering.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><th class=\"has-text-align-left\" data-align=\"left\">PV system and exposure<\/th><th class=\"has-text-align-left\" data-align=\"left\">SPD type<\/th><th class=\"has-text-align-left\" data-align=\"left\">Ucpv class<\/th><th class=\"has-text-align-left\" data-align=\"left\">Pouvoir de d\u00e9charge<\/th><th class=\"has-text-align-left\" data-align=\"left\">Location<\/th><\/tr><\/thead><tbody><tr><td class=\"has-text-align-left\" data-align=\"left\">Residential rooftop, no external LPS<\/td><td class=\"has-text-align-left\" data-align=\"left\">Type 2<\/td><td class=\"has-text-align-left\" data-align=\"left\">Match system (600 \/ 1000 V)<\/td><td class=\"has-text-align-left\" data-align=\"left\">In sized to exposure; Imax with margin<\/td><td class=\"has-text-align-left\" data-align=\"left\">Inverter DC input; add array end if run &gt; ~10 m<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\">Commercial rooftop, no external LPS<\/td><td class=\"has-text-align-left\" data-align=\"left\">Type 2<\/td><td class=\"has-text-align-left\" data-align=\"left\">1000 \/ 1500 V<\/td><td class=\"has-text-align-left\" data-align=\"left\">Higher In for repeated duty<\/td><td class=\"has-text-align-left\" data-align=\"left\">Inverter DC input and combiner box<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\">Commercial rooftop with LPS present<\/td><td class=\"has-text-align-left\" data-align=\"left\">Type 1+2<\/td><td class=\"has-text-align-left\" data-align=\"left\">1000 \/ 1500 V<\/td><td class=\"has-text-align-left\" data-align=\"left\">Iimp (10\/350&nbsp;\u00b5s) plus In\/Imax<\/td><td class=\"has-text-align-left\" data-align=\"left\">Inverter DC input and combiner box<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\">Exposed ground-mount \/ hilltop \/ high flash density<\/td><td class=\"has-text-align-left\" data-align=\"left\">Type 1+2<\/td><td class=\"has-text-align-left\" data-align=\"left\">1500 V<\/td><td class=\"has-text-align-left\" data-align=\"left\">Iimp rated for partial lightning current<\/td><td class=\"has-text-align-left\" data-align=\"left\">Combiner and recombiner boxes; inverter DC input<\/td><\/tr><tr><td class=\"has-text-align-left\" data-align=\"left\">Utility-scale free-field array<\/td><td class=\"has-text-align-left\" data-align=\"left\">Type 1+2<\/td><td class=\"has-text-align-left\" data-align=\"left\">1500 V<\/td><td class=\"has-text-align-left\" data-align=\"left\">High Iimp and In; remote signaling<\/td><td class=\"has-text-align-left\" data-align=\"left\">Every combiner\/recombiner and inverter station, per protection zones<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Notice what the matrix does not include: a battery or energy-storage DC bus. IEC 61643-31 and IEC 61643-32 cover the PV generator and inverter DC side up to 1500 V DC; they explicitly do not cover PV systems with energy storage. A battery DC bus needs its surge protection assessed under its own requirements, so do not assume a PV-string SPD is a drop-in for the storage side \u2014 specify that separately.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote has-palette-color-9-color has-text-color has-link-color wp-elements-20 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 wp-elements-21\">The mistakes that undersize or void a PV DC SPD<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Most failed or ineffective PV surge protection traces back to a short list of avoidable errors. Each one has a direct consequence.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Using an AC SPD on the DC side.<\/strong>&nbsp;No DC-capable disconnector, wrong voltage basis \u2014 a fire risk, not a protection device.<\/li>\n\n\n\n<li><strong>Sizing Ucpv to the nominal voltage.<\/strong>&nbsp;Ignoring the cold-morning Voc rise overstresses the device and trips its thermal disconnector early. Always size to 1.2 \u00d7 the maximum Voc.<\/li>\n\n\n\n<li><strong>Over-long or oversized strings.<\/strong>&nbsp;A string whose Voc pushes Ucpv past the 1500&nbsp;V class leaves no compliant SPD; fix it at design time by shortening the string.<\/li>\n\n\n\n<li><strong>Ignoring Iscpv.<\/strong>&nbsp;An SPD with a short-circuit withstand below the array&#8217;s fault current can fail violently instead of disconnecting cleanly.<\/li>\n\n\n\n<li><strong>Leads too long.<\/strong>&nbsp;Exceeding the 0.5&nbsp;m connecting-lead target adds inductive voltage and defeats a low Up.<\/li>\n\n\n\n<li><strong>Doubling up on an integrated SPD.<\/strong>&nbsp;Fitting an external device beside the inverter&#8217;s own coordinated SPD protects nothing new and adds a failure point \u2014 put the effort at the unprotected array end.<\/li>\n\n\n\n<li><strong>Uncoordinated stages.<\/strong>&nbsp;Two SPDs with no decoupling distance or defined inductor can leave the downstream device overstressed. Keep ~10&nbsp;m between stages or follow the maker&#8217;s coordination data.<\/li>\n\n\n\n<li><strong>No monitoring on unattended arrays.<\/strong>&nbsp;A red window on a rooftop combiner box no one opens means months of unprotected operation; specify the remote contact.<\/li>\n<\/ul>\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 wp-elements-22\">Turn the selection into an RFQ line<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">A selection is only useful once it becomes something a supplier can quote against without a second round of questions. The reader job at the end of this process is a single, unambiguous specification line. Capture these fields and an enquiry can be answered in one reply:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Application and standard:<\/strong>&nbsp;PV DC side, to IEC 61643-31; state Type 2 or Type 1+2.<\/li>\n\n\n\n<li><strong>System voltage class and Ucpv:<\/strong>&nbsp;the 600 \/ 1000 \/ 1500 V class and the minimum Ucpv from the 1.2 \u00d7 Voc calculation.<\/li>\n\n\n\n<li><strong>Array maximum Voc:<\/strong>&nbsp;the figure Ucpv was sized against, so the supplier can verify the margin.<\/li>\n\n\n\n<li><strong>Discharge rating:<\/strong>&nbsp;required In and Imax (8\/20&nbsp;\u00b5s), and Iimp (10\/350&nbsp;\u00b5s) for a Type 1+2 device.<\/li>\n\n\n\n<li><strong>Voltage protection level:<\/strong>&nbsp;the maximum acceptable Up, derived from the inverter&#8217;s DC withstand voltage.<\/li>\n\n\n\n<li><strong>Short-circuit withstand:<\/strong>&nbsp;the minimum Iscpv from the array short-circuit calculation, and whether an external backup device is expected.<\/li>\n\n\n\n<li><strong>Configuration and poles:<\/strong>&nbsp;standard 2-pole or Y-configuration, matched to the earthing arrangement.<\/li>\n\n\n\n<li><strong>Installation point and monitoring:<\/strong>&nbsp;inverter input, combiner, or recombiner; DIN-rail format; and whether a remote signaling contact is required.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">That line removes the guesswork on both sides and is the difference between a quote and a conversation.<\/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 wp-elements-23\">Recommended DC SPD by project type<\/h2>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">Bringing the method back to real decisions, here is how the specification typically lands for four common projects, mapped to the two JUTRION solar DC series \u2014 JRSPD-40DC-II (Type 2) and JRSPD-40DC-I+II (Type 1+2), both to IEC 61643-31, up to DC 1500 V, 40 kA Imax.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Residential rooftop string inverter (no LPS):<\/strong>&nbsp;a Type 2 device (JRSPD-40DC-II class) at the inverter DC input, Ucpv matched to the string&#8217;s cold-morning Voc, sized for occasional induced surges. Add a second at the array end only if the DC run is long.<\/li>\n\n\n\n<li><strong>Commercial rooftop (no LPS):<\/strong>&nbsp;Type 2 at both the combiner box and the inverter DC input, a higher nominal discharge current for repeated duty, and Up checked against the inverter&#8217;s DC withstand.<\/li>\n\n\n\n<li><strong>Exposed ground-mount or utility array:<\/strong>&nbsp;Type 1+2 (JRSPD-40DC-I+II class) with a real Iimp rating at combiner and recombiner boxes, 1500 V class, and a remote signaling contact for plant monitoring \u2014 this is where the partial-lightning-current capability earns its cost.<\/li>\n\n\n\n<li><strong>Array with a lightning protection system:<\/strong>&nbsp;Type 1+2 wherever separation distance to down-conductors cannot be maintained, coordinated with the LPS design rather than chosen in isolation.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Specify the four inputs first, size Ucpv to 1.2 \u00d7 the real maximum Voc, choose the type from lightning exposure, then confirm Up, short-circuit withstand, the thermal disconnector, configuration, and earthing against the datasheet. If you want those figures checked against a specific array before you order, the&nbsp;<a href=\"https:\/\/jutrion.com\/fr\/spd\/\">JUTRION AC &amp; DC surge protective device range<\/a>&nbsp;lists the DC series with the ratings this guide asks for, and the engineering team can confirm the match for your string voltage and site exposure.<\/p>\n\n\n\n<p class=\"has-large-font-size wp-block-paragraph\"><strong>References<\/strong><\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><a href=\"https:\/\/webstore.iec.ch\/en\/publication\/26931\" target=\"_blank\" rel=\"noopener\">IEC 61643-31:2018<\/a>&nbsp;\u2014 Low-voltage surge protective devices, Part 31: Requirements and test methods for SPDs for photovoltaic installations.<\/li>\n\n\n\n<li><a href=\"https:\/\/webstore.iec.ch\/en\/publication\/30774\" target=\"_blank\" rel=\"noopener\">IEC 61643-32:2017<\/a>&nbsp;\u2014 Low-voltage surge protective devices, Part 32: SPDs connected to the DC side of photovoltaic installations, selection and application principles.<\/li>\n\n\n\n<li>IEC 62305 series \u2014 Protection against lightning (risk assessment and lightning protection system coordination).<\/li>\n\n\n\n<li>IEC 62548 \u2014 Photovoltaic (PV) arrays: design requirements (basis for array maximum short-circuit current).<\/li>\n\n\n\n<li>IEC 60364-5-53 \u2014 Low-voltage electrical installations: selection and erection of electrical equipment, isolation, switching and control (SPD connection and conductor sizing).<\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"<p>Fast answer: how to specify a DC SPD for a solar array Choose a DC SPD by four inputs: the array&#8217;s maximum open-circuit voltage, its maximum short-circuit current, whether a lightning protection system is present, and the earthing arrangement. Size the maximum continuous operating voltage to&nbsp;Ucpv \u2265 1.2 \u00d7 the array&#8217;s maximum Voc&nbsp;(IEC 61643-32), pick&nbsp;Type [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":1868,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-1855","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\/1855","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=1855"}],"version-history":[{"count":3,"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/posts\/1855\/revisions"}],"predecessor-version":[{"id":1873,"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/posts\/1855\/revisions\/1873"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/media\/1868"}],"wp:attachment":[{"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/media?parent=1855"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/categories?post=1855"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/jutrion.com\/fr\/wp-json\/wp\/v2\/tags?post=1855"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}