{"id":58301,"date":"2025-11-12T10:13:24","date_gmt":"2025-11-12T09:13:24","guid":{"rendered":"https:\/\/lcsn2025.dev-labaleine.fr\/?p=58301"},"modified":"2026-10-27T11:03:45","modified_gmt":"2026-10-27T10:03:45","slug":"understanding-transformer-temperature-rise-and-insulation-classes","status":"publish","type":"post","link":"https:\/\/www.lecosinus.fr\/en\/comprendre-lechauffement-et-les-classes-disolation-des-transformateurs\/","title":{"rendered":"Understanding Transformer Heating and Insulation Classes"},"content":{"rendered":"<p class=\"wp-block-paragraph translation-block\">At Le Cosinus, we have been manufacturing and supporting <a href=\"https:\/\/www.lecosinus.fr\/en\/transformers\/\" data-type=\"link\" data-id=\"https:\/\/www.lecosinus.fr\/transformateurs\/\" target=\"_blank\" rel=\"noreferrer noopener\">transformers<\/a>,, inductors and DC power supplies for nearly 80 years. But behind every transformer there is much more than just a component: it ensures the continuity and transfer of energy. And to function, it must manage an unavoidable reality: heating.\u202f<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"1024\" src=\"https:\/\/www.lecosinus.fr\/wp-content\/uploads\/2026\/09\/Heat-under-control.jpg\" alt=\"Comment prot\u00e9ger un transformateur de la chaleur\" class=\"wp-image-86848\" srcset=\"https:\/\/www.lecosinus.fr\/wp-content\/uploads\/2026\/09\/Heat-under-control.jpg 1200w, https:\/\/www.lecosinus.fr\/wp-content\/uploads\/2026\/09\/Heat-under-control-300x300.jpg 300w, https:\/\/www.lecosinus.fr\/wp-content\/uploads\/2026\/09\/Heat-under-control-1024x1024.jpg 1024w, https:\/\/www.lecosinus.fr\/wp-content\/uploads\/2026\/09\/Heat-under-control-150x150.jpg 150w, https:\/\/www.lecosinus.fr\/wp-content\/uploads\/2026\/09\/Heat-under-control-768x768.jpg 768w, https:\/\/www.lecosinus.fr\/wp-content\/uploads\/2026\/09\/Heat-under-control-12x12.jpg 12w, https:\/\/www.lecosinus.fr\/wp-content\/uploads\/2026\/09\/Heat-under-control-600x600.jpg 600w, https:\/\/www.lecosinus.fr\/wp-content\/uploads\/2026\/09\/Heat-under-control-100x100.jpg 100w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\">Overheating is a normal phenomenon to control<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">When a transformer is running, it generates an electromagnetic field, and this produces heat.\u202fThis heat appears mainly in:&nbsp;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The windings, by joule losses, because of the resistance of the conducting wires.&nbsp;<\/li>\n<\/ul>\n\n\n\n<ul class=\"wp-block-list\">\n<li>The magnetic core, \"iron losses\" because of eddy currents and hysteresis losses.&nbsp;<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">A little heat is normal if the heating standards are respected and the insulation is provided for these heating. So we pay attention to the surrounding temperature, ventilation, the charge, the environment, etc, so that everything works well and lasts over time.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading translation-block\">Insulation classes: protecting your equipment<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Transformers heat up when they are running, this is normal. Insulation is used to prevent damage to the equipment. Different insulating material tolerates heat differently, and insulation classes tell how far a transformer can go to see these insulators degrade abnormally.&nbsp;<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The insulation class is chosen according to the expected heat and the location where the transformer will be installed. The goal is simple: for the transformer to remain sustainable, whatever the conditions.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Heating class and maximum temperatures of the insulation<\/h2>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><tbody><tr><td>Class&nbsp;<\/td><td>Warm-up (Ta 40\u00b0)&nbsp;<\/td><td>Max Temperature&nbsp;<\/td><\/tr><tr><td>Has&nbsp;<\/td><td>60\u00b0C\u202f&nbsp;<\/td><td>105\u00b0C\u202f&nbsp;<\/td><\/tr><tr><td>E\u202f&nbsp;<\/td><td>75\u00b0C\u202f&nbsp;<\/td><td>120\u00b0C\u202f&nbsp;<\/td><\/tr><tr><td>B\u202f&nbsp;<\/td><td>80\u00b0C\u202f&nbsp;<\/td><td>130\u00b0C\u202f&nbsp;<\/td><\/tr><tr><td>F\u202f&nbsp;<\/td><td>100\u00b0C\u202f&nbsp;<\/td><td>155\u00b0C\u202f&nbsp;<\/td><\/tr><tr><td>H\u202f&nbsp;<\/td><td>125\u00b0C\u202f&nbsp;<\/td><td>180\u00b0C\u202f&nbsp;<\/td><\/tr><tr><td>C\u202f&nbsp;<\/td><td>150\u00b0C\u202f&nbsp;<\/td><td>&gt;180\u00b0C\u202f&nbsp;<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>Finding the right balance<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">A high insulation class does not necessarily mean the best solution. The aim is to find the right compromise between performance, cost and longevity.\u202fFor example, Class B is sufficient in a standard industrial environment often for low power, while F or H will be preferable for higher power or more demanding environments: high ambient temperature, continuous operation or limited space. We analyse all these parameters to ensure that your transformer always stays in its thermal comfort zone.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\"><strong>People first<\/strong><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Our sales and technical teams work together to offer simple, robust solutions adapted to the field. Here, there are no impersonal speeches or ready-made answers: only passionate, available and committed experts. Because in the end, trust is as important as technique.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">La qualit\u00e9 du circuit magn\u00e9tique influence les pertes fer et la temp\u00e9rature de fonctionnement. D\u00e9couvrez comment les t\u00f4les magn\u00e9tiques contribuent au rendement des transformateurs.\u00a0<\/p>\n\n\n\n<div class=\"hs-cta-embed hs-cta-simple-placeholder hs-cta-embed-185420320831\" style=\"max-width:100%;max-height:100%;width:700px;height:239.53125px\" data-hubspot-wrapper-cta-id=\"185420320831\">\n  <a href=\"https:\/\/cta-service-cms2.hubspot.com\/web-interactives\/public\/v1\/track\/redirect?encryptedPayload=AVxigLJ%2B8uzXIlYd5F1Cg72GDEo4S1p9zzkqyLAlT3McWV%2BDNRWsrtcQFwhBihGlWDL3nSWdQscvugwJIEM%2Blo0sWyqvQjAIafWdESsEYmcGkml4PxESyXNVWWZLqCNHgrHd%2BIsg8qUJHAayrn2LojP7LZPyflwCywOPcg8taJdeZJCXxpOTHuE%3D&amp;webInteractiveContentId=185420320831&amp;portalId=48243687\" target=\"_blank\" rel=\"noopener\">\n    <img decoding=\"async\" alt=\"Demande de devis Saisissez votre r&eacute;f&eacute;rence produit ou indiquer les caract&eacute;ristiques du produit recherch&eacute; &nbsp;\" loading=\"lazy\" src=\"https:\/\/no-cache.hubspot.com\/cta\/default\/48243687\/interactive-185420320831.png\" style=\"height: 100%;width: 100%;object-fit: fill\" \/>\n  <\/a>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/cta-service-cms2.hubspot.com\/web-interactives\/public\/v1\/track\/redirect?encryptedPayload=AVxigLJ%2B8uzXIlYd5F1Cg72GDEo4S1p9zzkqyLAlT3McWV%2BDNRWsrtcQFwhBihGlWDL3nSWdQscvugwJIEM%2Blo0sWyqvQjAIafWdESsEYmcGkml4PxESyXNVWWZLqCNHgrHd%2BIsg8qUJHAayrn2LojP7LZPyflwCywOPcg8taJdeZJCXxpOTHuE%3D&amp;webInteractiveContentId=185420320831&amp;portalId=48243687\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/cta-service-cms2.hubspot.com\/web-interactives\/public\/v1\/track\/redirect?encryptedPayload=AVxigLJ%2B8uzXIlYd5F1Cg72GDEo4S1p9zzkqyLAlT3McWV%2BDNRWsrtcQFwhBihGlWDL3nSWdQscvugwJIEM%2Blo0sWyqvQjAIafWdESsEYmcGkml4PxESyXNVWWZLqCNHgrHd%2BIsg8qUJHAayrn2LojP7LZPyflwCywOPcg8taJdeZJCXxpOTHuE%3D&amp;webInteractiveContentId=185420320831&amp;portalId=48243687\" target=\"_blank\" rel=\"noreferrer noopener\"><\/a><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>","protected":false},"excerpt":{"rendered":"<p>Chez Le Cosinus, nous fabriquons et accompagnons depuis pr\u00e8s de 80 ans des\u202ftransformateurs, inductances et alimentations \u00e9lectriques en courant continu. Mais derri\u00e8re chaque transformateur, il y a bien plus qu\u2019un simple composant : il assure la continuit\u00e9 et le transfert de l\u2019\u00e9nergie. Et pour fonctionner, il doit g\u00e9rer une r\u00e9alit\u00e9 incontournable : l\u2019\u00e9chauffement.\u202f&nbsp; L\u2019\u00e9chauffement d&rsquo;un [&hellip;]<\/p>\n","protected":false},"author":5,"featured_media":86848,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"_seopress_titles_title":"Transformateur : \u00e9chauffement et isolation | Le Cosinus","_seopress_titles_desc":"Le Cosinus con\u00e7oit depuis pr\u00e8s de 80 ans des transformateurs, inductances et alimentations DC, en ma\u00eetrisant un enjeu cl\u00e9 : l\u2019\u00e9chauffement.","_seopress_robots_index":"","_seopress_robots_follow":"","_seopress_robots_imageindex":"","_seopress_robots_snippet":"","_seopress_robots_primary_cat":"none","_seopress_robots_breadcrumbs":"","_seopress_robots_freeze_modified_date":"","_seopress_robots_custom_modified_date":"","_seopress_robots_canonical":"","_seopress_social_fb_title":"","_seopress_social_fb_desc":"","_seopress_social_fb_img":"","_seopress_social_fb_img_attachment_id":0,"_seopress_social_fb_img_width":0,"_seopress_social_fb_img_height":0,"_seopress_social_twitter_title":"","_seopress_social_twitter_desc":"","_seopress_social_twitter_img":"","_seopress_social_twitter_img_attachment_id":0,"_seopress_social_twitter_img_width":0,"_seopress_social_twitter_img_height":0,"_seopress_redirections_value":"","_seopress_redirections_enabled":"","_seopress_redirections_enabled_regex":"","_seopress_redirections_logged_status":"both","_seopress_redirections_param":"","_seopress_redirections_type":301,"_seopress_analysis_target_kw":"\u00e9chauffement de transformateurs,\u00e9chauffement,echauffement,lechauffement","_seopress_news_disabled":"","_seopress_video_disabled":"","_seopress_video":[],"_seopress_pro_schemas_manual":[],"_seopress_pro_rich_snippets_disable_all":"","_seopress_pro_rich_snippets_disable":[],"_seopress_pro_schemas":[],"content-type":"","footnotes":""},"categories":[24],"tags":[],"class_list":["post-58301","post","type-post","status-publish","format-standard","has-post-thumbnail","category-securite"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.lecosinus.fr\/en\/wp-json\/wp\/v2\/posts\/58301","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.lecosinus.fr\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.lecosinus.fr\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.lecosinus.fr\/en\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/www.lecosinus.fr\/en\/wp-json\/wp\/v2\/comments?post=58301"}],"version-history":[{"count":28,"href":"https:\/\/www.lecosinus.fr\/en\/wp-json\/wp\/v2\/posts\/58301\/revisions"}],"predecessor-version":[{"id":96639,"href":"https:\/\/www.lecosinus.fr\/en\/wp-json\/wp\/v2\/posts\/58301\/revisions\/96639"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.lecosinus.fr\/en\/wp-json\/wp\/v2\/media\/86848"}],"wp:attachment":[{"href":"https:\/\/www.lecosinus.fr\/en\/wp-json\/wp\/v2\/media?parent=58301"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.lecosinus.fr\/en\/wp-json\/wp\/v2\/categories?post=58301"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.lecosinus.fr\/en\/wp-json\/wp\/v2\/tags?post=58301"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}