{"id":2170,"date":"2026-08-07T15:00:00","date_gmt":"2026-08-07T07:00:00","guid":{"rendered":"https:\/\/lbajiele.com\/news\/dry-type-insulation-temperature-class-selection-guide\/"},"modified":"2026-08-08T16:28:12","modified_gmt":"2026-08-08T08:28:12","slug":"dry-type-insulation-temperature-class-selection-guide","status":"publish","type":"post","link":"https:\/\/lbajiele.com\/vi\/blog\/dry-type-insulation-temperature-class-selection-guide\/","title":{"rendered":"H\u01b0\u1edbng d\u1eabn l\u1ef1a ch\u1ecdn C\u1ea5p nhi\u1ec7t \u0111\u1ed9 v\u00e0 C\u00e1ch \u0111i\u1ec7n lo\u1ea1i kh\u00f4"},"content":{"rendered":"<div class=\"b2b-article\">\n<p style=\"margin:0 0 16px;line-height:1.7\"><strong>Dry type insulation and temperature class<\/strong> choices decide whether an indoor unit runs inside its thermal budget\u2014or ages quietly behind a closed door.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">Buyers who pick a familiar class without ambient and airflow data often discover derating, fan noise, or hot-spot alarms after energization. This guide separates the labels, lists RFQ fields, and flags unfit paths.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">Lock thermal class with the room plan before cable tray freeze.<\/p>\n<figure style=\"margin:26px 0;text-align:center\"><img decoding=\"async\" style=\"max-width:640px;width:100%;height:auto;display:block;margin:0 auto;border-radius:8px\" alt=\"Dry type insulation and temperature class selection overview\" src=\"https:\/\/lbajiele.com\/wp-content\/uploads\/2026\/07\/315kva-dry-type-power-specifications-applications-product.webp\" \/><\/figure>\n<nav class=\"b2b-toc\" style=\"background:#f5f8fa;padding:16px 20px;border-radius:8px;margin:0 0 24px\">\n<h2 id=\"contents\" style=\"margin:42px 0 14px;scroll-margin-top:96px\">Contents<\/h2>\n<ul style=\"margin:0 0 18px 1.2em;line-height:1.7\">\n<li style=\"margin:0 0 8px\"><a href=\"#part-1-when-insulation-class-becomes-a-room-decision\">Part 1. When insulation class becomes a room decision<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-2-rfq-fields-that-keep-thermal-bids-comparable\">Part 2. RFQ fields that keep thermal bids comparable<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-3-insulation-class-versus-temperature-rise-class\">Part 3. Insulation class versus temperature rise class<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-4-ambient-enclosure-and-ventilation-interactions\">Part 4. Ambient, enclosure, and ventilation interactions<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-5-drawings-and-checks-before-order-release\">Part 5. Drawings and checks before order release<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-6-shortlist-dry-type-series-after-thermal-limits-are-written\">Part 6. Shortlist dry type series after thermal limits are written<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-7-thermal-selection-mistakes-that-overheat-rooms\">Part 7. Thermal-selection mistakes that overheat rooms<\/a><\/li>\n<\/ul>\n<\/nav>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-1-when-insulation-class-becomes-a-room-decision\">Part 1. When insulation class becomes a room decision<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">Indoor dry type units sit close to occupied spaces and shared ventilation paths.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">Class selection is therefore a room interface problem, not only a catalog preference.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">For adjacent indoor thermal and install notes, review the <a href=\"https:\/\/lbajiele.com\/vi\/blog\/transformer-temperature-rise-class-what-to-specify-in-procurement\/\">temperature rise class guide<\/a> v\u00e0 <a href=\"https:\/\/lbajiele.com\/vi\/blog\/dry-type-transformer-indoor-installation-ventilation-clearance-requirements\/\">dry type indoor installation guide<\/a>.<\/p>\n<blockquote>\n<p style=\"margin:0 0 16px;line-height:1.7\"><strong>Important:<\/strong> Do not freeze insulation class before ambient, rise limits, and ventilation are written into the RFQ (<a href=\"https:\/\/webstore.iec.ch\/en\/publication\/612\" rel=\"nofollow noopener\" target=\"_blank\">IEC 60076-11<\/a>).<\/p>\n<\/blockquote>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-2-rfq-fields-that-keep-thermal-bids-comparable\">Part 2. RFQ fields that keep thermal bids comparable<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">Ask suppliers to quote the same ambient and rise package.<\/p>\n<figure style=\"margin:26px 0;text-align:center\"><img decoding=\"async\" style=\"max-width:640px;width:100%;height:auto;display:block;margin:0 auto;border-radius:8px\" alt=\"Ambient and rise inputs for dry type transformer quotations\" src=\"https:\/\/lbajiele.com\/wp-content\/uploads\/2026\/07\/315kva-dry-type-power-specifications-applications-cover.webp\" \/><\/figure>\n<table style=\"width:100%;border-collapse:collapse\">\n<thead>\n<tr>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">RFQ item<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">Why it matters<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">Send with quote<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Insulation \/ temperature class<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Thermal capability label<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Yes<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Temperature rise limits<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Comparable thermal bids<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Yes<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Rated kVA and voltage combination<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Continuous sizing basis<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Yes<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Cooling method and enclosure<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Air path and IP interfaces<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Yes<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">No-load and load losses<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Heat to be rejected<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Yes<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Short-circuit impedance<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Protection coordination<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Yes<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p style=\"margin:0 0 16px;line-height:1.7\">Include maximum ambient and altitude if relevant.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-3-insulation-class-versus-temperature-rise-class\">Part 3. Insulation class versus temperature rise class<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">Insulation class describes material temperature capability; rise class describes allowed temperature rise above ambient.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">Mixing the two labels without ambient data produces false confidence.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">Write both into the RFQ in plain language.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-4-ambient-enclosure-and-ventilation-interactions\">Part 4. Ambient, enclosure, and ventilation interactions<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">Enclosures and blocked vents raise effective ambient at the windings.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">Forced-air stages change both capacity and sound; state which stages are allowed.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">Civil and electrical teams must share one ventilation assumption.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-5-drawings-and-checks-before-order-release\">Part 5. Drawings and checks before order release<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">Request GA drawings with ventilation openings, clearances, and any fan locations.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">Confirm vector group and tap range with the single-line diagram.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">Record the ambient basis used for design in the project file.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-6-shortlist-dry-type-series-after-thermal-limits-are-written\">Part 6. Shortlist dry type series after thermal limits are written<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\"><strong>Product recommendation:<\/strong> After thermal limits are written, open the <a href=\"https:\/\/lbajiele.com\/vi\/transformer\/\">transformer product category<\/a> and prioritize the <a href=\"https:\/\/lbajiele.com\/vi\/san-pham\/scb-resin-insulation-dry-transformer-series\/\">SC(B) resin insulated dry transformer series<\/a>, with the <a href=\"https:\/\/lbajiele.com\/vi\/san-pham\/s-m-oil-immersed-power-transformer\/\">S\u25a1-M oil-immersed power transformer series<\/a> only if an outdoor oil alternative re-enters the study.<\/p>\n<figure style=\"margin:26px 0;text-align:center\"><img decoding=\"async\" style=\"max-width:640px;width:100%;height:auto;display:block;margin:0 auto;border-radius:8px\" alt=\"Dry type transformer series for insulation class planning\" src=\"https:\/\/lbajiele.com\/wp-content\/uploads\/2026\/07\/315kva-dry-type-power-specifications-applications-body.webp\" \/><\/figure>\n<table style=\"width:100%;border-collapse:collapse\">\n<thead>\n<tr>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">Better fit<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">Needs more study<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Ambient and rise stated early<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Class chosen from habit alone<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Ventilation fixed with enclosure<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Layout frozen before airflow review<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Losses and impedance included<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Thermal class quoted without electrical package<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p style=\"margin:0 0 16px;line-height:1.7\">Submit ratings and room notes through <a href=\"https:\/\/lbajiele.com\/vi\/contact-us\/\">Li\u00ean h\u1ec7 v\u1edbi ch\u00fang t\u00f4i<\/a> for catalog confirmation.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-7-thermal-selection-mistakes-that-overheat-rooms\">Part 7. Thermal-selection mistakes that overheat rooms<\/h2>\n<ul style=\"margin:0 0 18px 1.2em;line-height:1.7\">\n<li style=\"margin:0 0 8px\">Treating insulation class as interchangeable with rise class.<\/li>\n<li style=\"margin:0 0 8px\">Omitting ambient from the RFQ.<\/li>\n<li style=\"margin:0 0 8px\">Upgrading enclosures without revisiting airflow.<\/li>\n<li style=\"margin:0 0 8px\">Ignoring fan noise when forced air is required.<\/li>\n<li style=\"margin:0 0 8px\">Freezing room layout before thermal class is set.<\/li>\n<li style=\"margin:0 0 8px\">Comparing bids on different ambient assumptions.<\/li>\n<\/ul>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"faq\">C\u00e2u h\u1ecfi th\u01b0\u1eddng g\u1eb7p<\/h2>\n<h3 style=\"margin:28px 0 12px\">What is the difference between insulation class and temperature rise?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">Insulation class is material capability; temperature rise is the allowed rise above ambient\u2014both need ambient context.<\/p>\n<h3 style=\"margin:28px 0 12px\">Can a higher insulation class fix a hot room?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">Not by itself; ventilation, enclosure, and ambient still govern usable margin.<\/p>\n<h3 style=\"margin:28px 0 12px\">Which data belong in a dry type thermal RFQ?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">State ambient, rise limits, class labels, kVA\/voltage, cooling\/enclosure, losses, and impedance together.<\/p>\n<h3 style=\"margin:28px 0 12px\">Do fans change the class decision?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">Forced-air stages can raise capacity but add noise and maintenance; define allowed stages in the RFQ.<\/p>\n<h3 style=\"margin:28px 0 12px\">When should altitude be included?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">Whenever the site is above the standard reference altitude used by the governing specification.<\/p>\n<h3 style=\"margin:28px 0 12px\">Should oil immersed options stay in the comparison?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">Only if outdoor placement and liquid interfaces are still open; otherwise keep the dry type thermal package focused.<\/p>\n<h3 style=\"margin:28px 0 12px\">What should buyers send suppliers?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">Send room ambient, ventilation limits, ratings needs, and required drawings with the RFQ.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"references\">References<\/h2>\n<ul style=\"margin:0 0 18px 1.2em;line-height:1.7\">\n<li style=\"margin:0 0 8px\"><a href=\"https:\/\/webstore.iec.ch\/en\/publication\/612\" rel=\"nofollow noopener\" target=\"_blank\">M\u00e1y bi\u1ebfn \u00e1p kh\u00f4 IEC 60076-11<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"https:\/\/webstore.iec.ch\/en\/publication\/590\" rel=\"nofollow noopener\" target=\"_blank\">IEC 60076-2 temperature rise<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"https:\/\/standards.ieee.org\/ieee\/C57.12.01\/1021\/\" rel=\"nofollow noopener\" target=\"_blank\">IEEE C57.12.01 dry-type general requirements<\/a><\/li>\n<\/ul>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>Dry type insulation and temperature class choices decide whether an indoor unit runs inside its thermal budget\u2014or ages quietly behind a closed door. Buyers who pick a familiar class without ambient and airflow data often discover derating, fan noise, or hot-spot alarms after energization. This guide separates the labels, lists RFQ fields, and flags unfit [&hellip;]<\/p>\n","protected":false},"author":5,"featured_media":2049,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[31],"tags":[],"class_list":["post-2170","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"blocksy_meta":[],"acf":[],"_links":{"self":[{"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/posts\/2170","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/comments?post=2170"}],"version-history":[{"count":1,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/posts\/2170\/revisions"}],"predecessor-version":[{"id":2172,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/posts\/2170\/revisions\/2172"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/media\/2049"}],"wp:attachment":[{"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/media?parent=2170"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/categories?post=2170"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lbajiele.com\/vi\/wp-json\/wp\/v2\/tags?post=2170"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}