{"id":18999,"date":"2026-10-12T16:40:43","date_gmt":"2026-10-12T08:40:43","guid":{"rendered":"https:\/\/www.wehopower.com\/news\/power-supply-derating-curves-read-input-voltage-and-temperature-separately\/"},"modified":"2026-10-12T16:40:43","modified_gmt":"2026-10-12T08:40:43","slug":"power-supply-derating-curves-read-input-voltage-and-temperature-separately","status":"publish","type":"news","link":"https:\/\/www.wehopower.com\/ur\/news\/power-supply-derating-curves-read-input-voltage-and-temperature-separately\/","title":{"rendered":"Power Supply Derating Curves: Read Input Voltage and Temperature Separately"},"content":{"rendered":"<p>A <strong>power supply derating curve<\/strong> answers a conditional question: how much output is permitted under the conditions named on that curve? Two graphs on the same sheet are not automatically interchangeable. An input-voltage graph and an ambient-temperature graph can constrain the same application for different reasons.<\/p>\n<p>This guide uses the source-controlled WEHO HDR-60-24 as the product reference. The specimen is marked 24V, 2.5A, corresponding to a 60W nominal output. That identifies the starting point. It does not establish that the full output is available at every input, temperature, orientation or enclosure condition.<\/p>\n<figure><img fetchpriority=\"high\" decoding=\"async\" src=\"https:\/\/www.wehopower.com\/wp-content\/uploads\/2026\/10\/03-product-detail-39.png\" alt=\"Power Supply Derating Curves: Read Input Voltage and Temperature Separately  title=\" width=\"1536\" height=\"1024\" power supply derating curves: read input voltage and temperature separately title=\"\"><figcaption>\u72ec\u7acb\u6280\u672f\u6838\u9a8c\u901a\u8fc7 \u00b7 Original product reference, uniformly resized without repainting the casing, trademark, label or terminals. This is not a new installed application scene.<\/figcaption><\/figure>\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_86 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">\u0645\u0646\u062f\u0631\u062c\u0627\u062a \u06a9\u0627 \u062c\u062f\u0648\u0644<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">\u0679\u0648\u06af\u0644 \u06a9\u0631\u06cc\u06ba\u06d4<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewbox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewbox=\"0 0 24 24\" version=\"1.2\" baseprofile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.wehopower.com\/ur\/news\/power-supply-derating-curves-read-input-voltage-and-temperature-separately\/#Read_the_axes_and_notes_before_reading_the_curve\" >Read the axes and notes before reading the curve<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.wehopower.com\/ur\/news\/power-supply-derating-curves-read-input-voltage-and-temperature-separately\/#Keep_the_two_checks_separate\" >Keep the two checks separate<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.wehopower.com\/ur\/news\/power-supply-derating-curves-read-input-voltage-and-temperature-separately\/#Use_installed_temperature_rather_than_room_temperature\" >Use installed temperature rather than room temperature<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.wehopower.com\/ur\/news\/power-supply-derating-curves-read-input-voltage-and-temperature-separately\/#Keep_body_size_and_clearance_distinct\" >Keep body size and clearance distinct<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.wehopower.com\/ur\/news\/power-supply-derating-curves-read-input-voltage-and-temperature-separately\/#Make_the_purchasing_decision_traceable\" >Make the purchasing decision traceable<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.wehopower.com\/ur\/news\/power-supply-derating-curves-read-input-voltage-and-temperature-separately\/#Is_nominal_60W_always_available\" >Is nominal 60W always available?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.wehopower.com\/ur\/news\/power-supply-derating-curves-read-input-voltage-and-temperature-separately\/#Can_one_curve_cover_both_input_and_temperature\" >Can one curve cover both input and temperature?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.wehopower.com\/ur\/news\/power-supply-derating-curves-read-input-voltage-and-temperature-separately\/#What_should_be_sent_with_a_technical_enquiry\" >What should be sent with a technical enquiry?<\/a><\/li><\/ul><\/li><\/ul><\/nav><\/div>\n<h2><span class=\"ez-toc-section\" id=\"Read_the_axes_and_notes_before_reading_the_curve\"><\/span>Read the axes and notes before reading the curve<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Start by identifying the exact model, document revision and meaning of each axis. A percentage of rated load is different from amperes; AC input voltage is different from cabinet temperature. Check which input, mounting orientation, airflow and output variant the graph assumes. A curve copied from a neighbouring HDR model is not a substitute for the ordered unit&#8217;s controlled sheet.<\/p>\n<p>Record the footnotes as part of the selection evidence. The retained complete HDR-60 sheet does not provide the model-specific input\/load and ambient-temperature\/load curves needed for a numeric decision. This is missing evidence, not a small curve that has been decoded. Request those controlled curves from the manufacturer; do not borrow a neighbouring model&#8217;s graph. Public and retained operating descriptions also differ, so this draft gives a reading method, not numeric thermal breakpoints or a universal combined derating formula.<\/p>\n<figure><img decoding=\"async\" src=\"https:\/\/www.wehopower.com\/wp-content\/uploads\/2026\/10\/01-application-a-42.png\" alt=\"Power Supply Derating Curves: Read Input Voltage and Temperature Separately  title=\" width=\"1536\" height=\"1024\" power supply derating curves: read input voltage and temperature separately title=\"\"><figcaption>\u72ec\u7acb\u6280\u672f\u6838\u9a8c\u901a\u8fc7 \u00b7 Source-referenced auxiliary-bay layout before termination beside a pallet-positioning fixture. Six supply clamps remain empty; no load compatibility, accepted ventilation spacing or thermal test is established.<\/figcaption><\/figure>\n<h2><span class=\"ez-toc-section\" id=\"Keep_the_two_checks_separate\"><\/span>Keep the two checks separate<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<table>\n<thead>\n<tr>\n<th>Check<\/th>\n<th>Question<\/th>\n<th>Evidence needed<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Input-related limit<\/td>\n<td>What output is permitted at the actual supply input?<\/td>\n<td>Controlled model-specific input\/load curve and site conditions<\/td>\n<\/tr>\n<tr>\n<td>Temperature-related limit<\/td>\n<td>What output is permitted at the air temperature around the installed supply?<\/td>\n<td>Controlled thermal curve, orientation and enclosure conditions<\/td>\n<\/tr>\n<tr>\n<td>Combined operating point<\/td>\n<td>How should simultaneous constraints be applied?<\/td>\n<td>Manufacturer&#8217;s stated rule or application confirmation<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Do not multiply two percentages merely because there are two graphs. Do not automatically take the lower percentage either unless the manufacturer&#8217;s instructions support that method. If combined low-input and high-temperature operation is relevant, include both conditions in the technical enquiry and obtain a documented answer.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Use_installed_temperature_rather_than_room_temperature\"><\/span>Use installed temperature rather than room temperature<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>A panel in a comfortable workshop may contain a warmer electrical compartment. Nearby contactors, drives and enclosure ventilation all affect the local environment. Define the relevant measurement location and test state with the equipment designer. A single outside-room reading is not proof that the internal thermal condition matches the graph.<\/p>\n<p>Record whether the cabinet is closed, which neighbouring equipment operates and how long the selected state lasts. Use actual observed data only after testing. A generated application image must not display a fabricated instrument reading or be described as proof that a thermal test passed.<\/p>\n<figure><img decoding=\"async\" src=\"https:\/\/www.wehopower.com\/wp-content\/uploads\/2026\/10\/02-application-b-40.png\" alt=\"Power Supply Derating Curves: Read Input Voltage and Temperature Separately  title=\" width=\"1536\" height=\"1024\" power supply derating curves: read input voltage and temperature separately title=\"\"><figcaption>\u72ec\u7acb\u6280\u672f\u6838\u9a8c\u901a\u8fc7 \u00b7 A different fixture-rack auxiliary service compartment at provisional pre-termination layout stage. It illustrates mounting\/access, not a measured burn-in or derating result.<\/figcaption><\/figure>\n<h2><span class=\"ez-toc-section\" id=\"Keep_body_size_and_clearance_distinct\"><\/span>Keep body size and clearance distinct<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>The HDR-60 mechanical evidence identifies a 52.5mm horizontal width, 90mm upright height and 54.5mm body depth. A separate rear mounting projection is shown in the drawing; it is not a replacement for body depth. The source supports rear DIN-rail mounting, not an arbitrary front bracket.<\/p>\n<p>Use the envelope to reserve physical space, then add the ordered unit&#8217;s required ventilation and service clearances. Filling every available gap with adjoining components can undermine the assumptions used for thermal selection. Do not infer a clearance from an illustration or use a ruler as a decorative substitute for engineering evidence.<\/p>\n<figure><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/www.wehopower.com\/wp-content\/uploads\/2026\/10\/04-engineering-context-43.png\" alt=\"Power Supply Derating Curves: Read Input Voltage and Temperature Separately  title=\" width=\"1536\" height=\"1024\" power supply derating curves: read input voltage and temperature separately title=\"\"><figcaption>\u72ec\u7acb\u6280\u672f\u6838\u9a8c\u901a\u8fc7 \u00b7 A curve-reading evidence worksheet. The complete retained sheet lacks the two required model-specific graphs; no manufacturer curves or numerical breakpoints are invented.<\/figcaption><\/figure>\n<h2><span class=\"ez-toc-section\" id=\"Make_the_purchasing_decision_traceable\"><\/span>Make the purchasing decision traceable<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>A useful release record contains the exact HDR-60-24 identity, controlled document revision, maximum load state, input condition, installed ambient and mounting arrangement. If a value remains unresolved, name it explicitly rather than borrowing a convenient limit from a catalogue summary. Preserve the original physical label unchanged in the accompanying product reference.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Is_nominal_60W_always_available\"><\/span>Is nominal 60W always available?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>No. Nominal output and permitted output at a particular operating point are different decisions.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Can_one_curve_cover_both_input_and_temperature\"><\/span>Can one curve cover both input and temperature?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Only if the manufacturer explicitly defines it that way. Separate axes and conditions need separate interpretation.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"What_should_be_sent_with_a_technical_enquiry\"><\/span>What should be sent with a technical enquiry?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The intended load, input extremes, measured or specified enclosure conditions and mounting layout. Ask how the exact revision handles their combination.<\/p>\n<p><a href=\"https:\/\/www.wehopower.com\/ur\/product\/60w-ultra-slim-step-shape-din-rail-power-supply-hdr-60\/\">Official HDR-60 product reference<\/a>. The original photograph and complete approved sheet accompany this local draft for revision-controlled review.<\/p>","protected":false},"excerpt":{"rendered":"<p>An HDR-60-24 review method that separates documented operating limits, cabinet temperature and the exact ordered revision.<\/p>","protected":false},"author":2,"featured_media":18995,"parent":0,"menu_order":103,"comment_status":"","ping_status":"","template":"","format":"standard","meta":{"_acf_changed":false,"_joinchat":[],"footnotes":""},"news_category":[149,284],"class_list":["post-18999","news","type-news","status-publish","format-standard","has-post-thumbnail","hentry","news_category-blog","news_category-product-articles","entry"],"acf":[],"post_mailing_queue_ids":[],"_links":{"self":[{"href":"https:\/\/www.wehopower.com\/ur\/wp-json\/wp\/v2\/news\/18999","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.wehopower.com\/ur\/wp-json\/wp\/v2\/news"}],"about":[{"href":"https:\/\/www.wehopower.com\/ur\/wp-json\/wp\/v2\/types\/news"}],"author":[{"embeddable":true,"href":"https:\/\/www.wehopower.com\/ur\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.wehopower.com\/ur\/wp-json\/wp\/v2\/comments?post=18999"}],"version-history":[{"count":0,"href":"https:\/\/www.wehopower.com\/ur\/wp-json\/wp\/v2\/news\/18999\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.wehopower.com\/ur\/wp-json\/wp\/v2\/media\/18995"}],"wp:attachment":[{"href":"https:\/\/www.wehopower.com\/ur\/wp-json\/wp\/v2\/media?parent=18999"}],"wp:term":[{"taxonomy":"news_category","embeddable":true,"href":"https:\/\/www.wehopower.com\/ur\/wp-json\/wp\/v2\/news_category?post=18999"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}