{"id":115122,"date":"2026-08-21T17:07:31","date_gmt":"2026-08-21T15:07:31","guid":{"rendered":"https:\/\/preprod.marechal.com\/overheating-expert-sheet\/"},"modified":"2026-09-10T15:12:49","modified_gmt":"2026-09-10T13:12:49","slug":"overheating-expert-sheet","status":"publish","type":"page","link":"https:\/\/marechal.com\/en\/overheating-expert-sheet\/","title":{"rendered":"Over heating expert sheet"},"content":{"rendered":"<header\n    class=\"hero-page hero-page--centered\"\n    >\n            <img class=\"hero-page__bg\" src=\"https:\/\/marechal.com\/wp-content\/uploads\/2026\/08\/marechal-header-expert-sheets-background-scaled.webp\" srcset=\"https:\/\/marechal.com\/wp-content\/uploads\/2026\/08\/marechal-header-expert-sheets-background-scaled.webp 2560w, https:\/\/marechal.com\/wp-content\/uploads\/2026\/08\/marechal-header-expert-sheets-background-300x101.webp 300w, https:\/\/marechal.com\/wp-content\/uploads\/2026\/08\/marechal-header-expert-sheets-background-1024x344.webp 1024w, https:\/\/marechal.com\/wp-content\/uploads\/2026\/08\/marechal-header-expert-sheets-background-768x258.webp 768w, https:\/\/marechal.com\/wp-content\/uploads\/2026\/08\/marechal-header-expert-sheets-background-1536x516.webp 1536w, https:\/\/marechal.com\/wp-content\/uploads\/2026\/08\/marechal-header-expert-sheets-background-2048x688.webp 2048w\" sizes=\"100vw\" alt=\"\" aria-hidden=\"true\" fetchpriority=\"high\" loading=\"eager\" decoding=\"async\" \/>\n        \n    <div class=\"hero-page__content\">\n        <div class=\"hero-page__container\">\n                                                <h1 class=\"hero-page__title\">OVERHEATING<br \/>\nexpert sheet<\/h1>                                                                    <\/div>\n    <\/div>\n\n        <\/header>\n\n\n\n<h3 class=\"wp-block-heading has-text-align-center\">Overheating is the main cause of damage to plug socket-outlets.<br> It is linked to the comprehensive resistance of 5 contacts in set:<\/h3>\n\n\n\n\n<div class=\"hotspots-image hotspots-image--w850\">\n    <div class=\"hotspots-image__media\">\n                <div class=\"hotspots-image__frame\">\n                            <img decoding=\"async\" class=\"hotspots-image__img\" src=\"https:\/\/marechal.com\/wp-content\/uploads\/2026\/08\/marechal-expert-sheet-heating-contacts.webp\" alt=\"\" \/>\n            \n                                            <button type=\"button\"\n                        class=\"hotspots-image__point is-active\"\n                        data-point=\"1\"\n                        data-group=\"1\"\n                        style=\"left:20.2%;top:40.9%;\"\n                        aria-label=\"Point 1\">\n                    <span class=\"hotspots-image__dot\"><\/span>\n                    <span class=\"hotspots-image__pulse\" aria-hidden=\"true\"><\/span>\n                <\/button>\n                                            <button type=\"button\"\n                        class=\"hotspots-image__point\"\n                        data-point=\"2\"\n                        data-group=\"2\"\n                        style=\"left:29.4%;top:43.5%;\"\n                        aria-label=\"Point 2\">\n                    <span class=\"hotspots-image__dot\"><\/span>\n                    <span class=\"hotspots-image__pulse\" aria-hidden=\"true\"><\/span>\n                <\/button>\n                                            <button type=\"button\"\n                        class=\"hotspots-image__point\"\n                        data-point=\"3\"\n                        data-group=\"3\"\n                        style=\"left:50%;top:48.6%;\"\n                        aria-label=\"Point 3\">\n                    <span class=\"hotspots-image__dot\"><\/span>\n                    <span class=\"hotspots-image__pulse\" aria-hidden=\"true\"><\/span>\n                <\/button>\n                                            <button type=\"button\"\n                        class=\"hotspots-image__point\"\n                        data-point=\"4\"\n                        data-group=\"4\"\n                        style=\"left:77.1%;top:40.9%;\"\n                        aria-label=\"Point 4\">\n                    <span class=\"hotspots-image__dot\"><\/span>\n                    <span class=\"hotspots-image__pulse\" aria-hidden=\"true\"><\/span>\n                <\/button>\n                    <\/div>\n\n                <ul class=\"hotspots-image__list\">\n                                            <li class=\"hotspots-image__leader is-active is-left\"\n                    data-point=\"1\"\n                    data-group=\"1\"\n                    style=\"--x:20.2%;--y:40.9%;--len:7.9%;--angle:267deg\">\n                                            <div class=\"hotspots-image__label\"><p><strong>1.<\/strong> The contact of the conductor in the clamp of the plug socket-outlet.<\/p>\n<\/div>\n                                    <\/li>\n                                            <li class=\"hotspots-image__leader\"\n                    data-point=\"2\"\n                    data-group=\"2\"\n                    style=\"--x:29.4%;--y:43.5%;--len:11.5%;--angle:295deg\">\n                                            <div class=\"hotspots-image__label\"><p><strong>2. and 3.<\/strong> The crimps at the 2 ends of the braid.<\/p>\n<\/div>\n                                    <\/li>\n                                            <li class=\"hotspots-image__leader\"\n                    data-point=\"3\"\n                    data-group=\"3\"\n                    style=\"--x:50%;--y:48.6%;--len:7.9%;--angle:75deg\">\n                                            <div class=\"hotspots-image__label\"><p><strong>4.<\/strong> The contact at the socket\/plug interface.<\/p>\n<\/div>\n                                    <\/li>\n                                            <li class=\"hotspots-image__leader is-left\"\n                    data-point=\"4\"\n                    data-group=\"4\"\n                    style=\"--x:77.1%;--y:40.9%;--len:8.1%;--angle:269deg\">\n                                            <div class=\"hotspots-image__label\"><p><strong>5.<\/strong> The conductor contact in the plug clamp.<\/p>\n<\/div>\n                                    <\/li>\n                    <\/ul>\n    <\/div>\n<\/div>\n\n\n<section class=\"expertise-section expertise-section--text expertise-section--dark expertise-section--text-center\">\n\n    \n        <div class=\"container\">\n                        \n            \n                                    <div class=\"expertise-section__text\">\n                        <p>The same care must be taken in the design and implementation of these five contacts.<\/p>\n                    <\/div>\n                                \n                    <\/div>\n\n    <\/section>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-center\">Quality of materials<\/h2>\n\n\n<section class=\"expertise-section expertise-section--text-image expertise-section--dark expertise-section--valign-top expertise-section--narrow expertise-section--col-img90\">\n\n    \n        <div class=\"container\">\n                        \n            \n                                <div class=\"expertise-section__cols\">\n                    <div class=\"expertise-section__col expertise-section__col--text\">\n                                                    <div class=\"expertise-section__text\"><p><strong>The choice of contact material is fundamental.<\/strong><\/p>\n<p>It must:<\/p>\n<ul>\n<li>Have the lowest possible contact resistance in order to avoid heat generation and, a fortiori, deterioration of the contact.<\/li>\n<li>Be sufficiently solid to offer a long time constant and high thermal inertia.<\/li>\n<li>Retain its electrical and mechanical properties for a long time, even in the event of accidental overheating, which could lead to accelerated oxidation (corrosion).<\/li>\n<li>Withstand electrical cut-off tests and the generation of electric arcs.<\/li>\n<\/ul>\n<\/div>                                            <\/div>\n                    <div class=\"expertise-section__col expertise-section__col--image\">\n                                                    <div class=\"expertise-section__image-wrap has-halo\"><div class=\"halo\" aria-hidden=\"true\"><\/div><img decoding=\"async\" src=\"https:\/\/marechal.com\/wp-content\/uploads\/2026\/08\/marechal-expert-sheets-materials.webp\" alt=\"\" loading=\"lazy\"><\/div>                                            <\/div>\n                <\/div>\n\n                    <\/div>\n\n    <\/section>\n\n\n<section class=\"expertise-section expertise-section--text expertise-section--dark expertise-section--text-center\">\n\n    \n        <div class=\"container\">\n                        \n            \n                                    <div class=\"expertise-section__text\">\n                        <p>According to these criteria, the most common materials offer:<\/p>\n                    <\/div>\n                                \n                    <\/div>\n\n    <\/section>\n\n\n<section class=\"expertise-section expertise-section--image expertise-section--dark\">\n\n    \n        <div class=\"container\">\n                        \n            \n                \n                                    <figure class=\"expertise-section__figure\">\n                        <img decoding=\"async\"\n                            src=\"https:\/\/marechal.com\/wp-content\/uploads\/2026\/08\/Groupe-4353.webp\"\n                            alt=\"\"\n                            loading=\"lazy\"\n                        >\n                                            <\/figure>\n                \n                    <\/div>\n\n    <\/section>\n\n\n<section class=\"expertise-section expertise-section--text expertise-section--dark expertise-section--text-center\">\n\n    \n        <div class=\"container\">\n                        \n            \n                                    <div class=\"expertise-section__text\">\n                        <p><strong>The material that best meets all the criteria is silver-nickel alloy.<\/strong><\/p>\n<p>It is commonly used by all electrical switch manufacturers and has therefore been selected for DECONTACTOR<sup>\u2122<\/sup> to guarantee the best electrical conduction performance in operation and switching.<\/p>\n                    <\/div>\n                                \n                    <\/div>\n\n    <\/section>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-center\">The force applied to the contact<\/h2>\n\n\n<section class=\"expertise-section expertise-section--image-text expertise-section--dark expertise-section--narrow\">\n\n    \n        <div class=\"container\">\n                        \n            \n                                <div class=\"expertise-section__cols\">\n                    <div class=\"expertise-section__col expertise-section__col--image\">\n                                                    <div class=\"expertise-section__image-wrap has-halo\"><div class=\"halo\" aria-hidden=\"true\"><\/div><img decoding=\"async\" src=\"https:\/\/marechal.com\/wp-content\/uploads\/2026\/08\/Groupe-4354.webp\" alt=\"\" loading=\"lazy\"><\/div>                                            <\/div>\n                    <div class=\"expertise-section__col expertise-section__col--text\">\n                                                    <div class=\"expertise-section__text\"><p><strong>The force applied to the contact is a key parameter that determines the quality of a contact.<\/strong><\/p>\n<p>A minimum force must be applied when inserting a plug into its socket and this must remain constant over time (whether used or not).<\/p>\n<\/div>                                            <\/div>\n                <\/div>\n\n                    <\/div>\n\n    <\/section>\n\n\n<section class=\"expertise-section expertise-section--text expertise-section--dark expertise-section--text-center\">\n\n    \n        <div class=\"container\">\n                        \n            \n                                    <div class=\"expertise-section__text\">\n                        <p><strong>MARECHAL<sup>\u00ae<\/sup> plug socket-outlets use end contacts with a spring on the socket side. <\/strong><\/p>\n<p>The contact pressure is generated by the compression of this spring, in line with the insertion force, without any friction.<br \/>\nThis spring is very precisely calibrated and its optimum compression range is perfectly calculated.<\/p>\n                    <\/div>\n                                \n                    <\/div>\n\n    <\/section>\n\n\n<section class=\"expertise-section expertise-section--text-image expertise-section--dark expertise-section--narrow\">\n\n    \n        <div class=\"container\">\n                        \n            \n                                <div class=\"expertise-section__cols\">\n                    <div class=\"expertise-section__col expertise-section__col--text\">\n                                                    <div class=\"expertise-section__text\"><ul>\n<li>This concept allows wide tolerances<\/li>\n<li>Removal of the plug, even of a large gauge, requires no effort<\/li>\n<li>The base contact spring of each gauge is calculated so that once the plug is fully connected in its socket, the spring is compressed by a certain length to deliver the required force<\/li>\n<li>The springs work within their optimum range of elasticity to maximise their service life<\/li>\n<li>The flexibility of the braid and spring ensures that the plug on the socket contact is always perfectly aligned with the cap on the plug contact. This braid is also calibrated so that once contact has been made, it does not come into friction with the spring and risk being damaged after a certain number of manipulations<\/li>\n<\/ul>\n<\/div>                                            <\/div>\n                    <div class=\"expertise-section__col expertise-section__col--image\">\n                                                    <div class=\"expertise-section__image-wrap\"><img decoding=\"async\" src=\"https:\/\/marechal.com\/wp-content\/uploads\/2026\/08\/Groupe-4356.webp\" alt=\"\" loading=\"lazy\"><\/div>                                            <\/div>\n                <\/div>\n\n                    <\/div>\n\n    <\/section>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-center\">Connection terminals (clamps)<\/h2>\n\n\n<section class=\"expertise-section expertise-section--text-image expertise-section--dark\">\n\n    \n        <div class=\"container\">\n                        \n            \n                                <div class=\"expertise-section__cols\">\n                    <div class=\"expertise-section__col expertise-section__col--text\">\n                                                    <div class=\"expertise-section__text\"><p><strong>Loose terminals (and the resulting overheating) are one of the main causes of failure.<\/strong><\/p>\n<p>It is due to various factors:<\/p>\n<ul>\n<li>Mobile plugs socket-outlets are often subjected to rough handling<\/li>\n<li>Plug socket-outlets and connectors are subject to the vibrations inherent in industrial installations<\/li>\n<li>The intermittent flow of current creates thermal cycles (expansion)<\/li>\n<li>Flexible conductors are made up of fine strands that settle into their de\ufb01nitive position after tightening<\/li>\n<li>Copper is a soft material with low elasticity, which deforms under moderate pressure, easily generated with a simple screw (creep phenomenon)<\/li>\n<\/ul>\n<p>If the terminal is fitted with a simple screw, the deformation of the copper induces a relaxation of the compression force. As a result, the contact resistance at the clamp increases and the temperature rapidly rises above an acceptable limit.<\/p>\n<p>Conversely, the DECONTACTOR<sup>\u2122<\/sup> is equipped with spring-lock terminals designed to compensate for the deformation (creep) of the copper and to resist shock and vibration: a constant force is applied to the conductor using a screw and a metal spring ring surrounding the body of the split terminal.<\/p>\n<\/div>                                            <\/div>\n                    <div class=\"expertise-section__col expertise-section__col--image\">\n                                                    <div class=\"expertise-section__image-wrap has-halo\"><div class=\"halo\" aria-hidden=\"true\"><\/div><img decoding=\"async\" src=\"https:\/\/marechal.com\/wp-content\/uploads\/2026\/08\/Groupe-4378.webp\" alt=\"\" loading=\"lazy\"><\/div>                                            <\/div>\n                <\/div>\n\n                    <\/div>\n\n    <\/section>\n\n\n<section class=\"expertise-section expertise-section--image-text expertise-section--dark\">\n\n    \n        <div class=\"container\">\n                        \n            \n                                <div class=\"expertise-section__cols\">\n                    <div class=\"expertise-section__col expertise-section__col--image\">\n                                                    <div class=\"expertise-section__image-wrap has-halo\"><div class=\"halo\" aria-hidden=\"true\"><\/div><img decoding=\"async\" src=\"https:\/\/marechal.com\/wp-content\/uploads\/2026\/07\/3bornes_en.webp\" alt=\"\" loading=\"lazy\"><\/div>                                            <\/div>\n                    <div class=\"expertise-section__col expertise-section__col--text\">\n                                                    <div class=\"expertise-section__text\"><p>Under the pressure of the screw, the split in the terminal body opens until it is held by the ring, which then deforms elliptically and elastically.<\/p>\n<p>The elasticity of the ring constantly compensates for the creep of the conductor. During thermal cycles caused by the intermittent flow of current, dimensional variations are compensated for. This elastic clamping also prevents loosening due to shock and vibration.<\/p>\n<p>MARECHAL<sup>\u00ae<\/sup> appliances use different constructions based on this same principle, depending on the size of the conductors to be connected. These terminals are reusable and provide a consistent and reliable connection quality that does not require tightening checks as specified by installation and maintenance regulations.<\/p>\n<\/div>                                            <\/div>\n                <\/div>\n\n                    <\/div>\n\n    <\/section>\n\n\n\n<h2 class=\"wp-block-heading has-text-align-center\">Capacity to withstand overloads (time constant)<\/h2>\n\n\n<section class=\"expertise-section expertise-section--text-image expertise-section--dark\">\n\n    \n        <div class=\"container\">\n                        \n            \n                                <div class=\"expertise-section__cols\">\n                    <div class=\"expertise-section__col expertise-section__col--text\">\n                                                    <div class=\"expertise-section__text\"><p><strong>Thermal equilibrium<br \/>\n<\/strong>An appliance subject to a current flow heats up, reaching a \u2018thermal equilibrium\u2019 after a certain period of time. This stabilisation is achieved when the heat generated by the resistance of the appliance is equal to the heat dissipated along the conductors and in the environment. A conventional parameter has been de\ufb01ned that can accurately measure the time constant, i.e. the time for which an appliance would reach its equilibrium temperature if this rise were linear (slope) and not degressive. This period amounts to 63% of the maximum temperature rise.<\/p>\n<p><strong>Overheating<br \/>\n<\/strong>By convention, temperature rises are expressed in Kelvin (K) to distinguish them from ambient temperatures in degrees Celsius or degrees Fahrenheit. The heating curve of an appliance is a function of its thermal equilibrium and its time constant. It is used to calculate its temperature rise for a given current and for a speci\ufb01c period.<\/p>\n<\/div>                                            <\/div>\n                    <div class=\"expertise-section__col expertise-section__col--image\">\n                                                    <div class=\"expertise-section__image-wrap has-halo\"><div class=\"halo\" aria-hidden=\"true\"><\/div><img decoding=\"async\" src=\"https:\/\/marechal.com\/wp-content\/uploads\/2026\/08\/Groupe-4358.webp\" alt=\"\" loading=\"lazy\"><\/div>                                            <\/div>\n                <\/div>\n\n                    <\/div>\n\n    <\/section>\n\n\n<section class=\"expertise-section expertise-section--text expertise-section--dark expertise-section--text-center\">\n\n    \n        <div class=\"container\">\n                        \n            \n                                    <div class=\"expertise-section__text\">\n                        <p>An industrial plug socket-outlet is rarely used for stable or continuous current operation.<br \/>\nThe DECONTACTOR<sup>\u2122<\/sup> is most often subjected to much more severe operating currents of the motor start-up type, and machinery with variable consumption cycles.<br \/>\nThe very long time constants or thermal inertia of the DECONTACTOR<sup>\u2122<\/sup> allow it to absorb current cycles without dif\ufb01culty and therefore give it a long service life.<br \/>\nThe material of its contacts can withstand accidental overheating without irreversible permanent damage.<\/p>\n                    <\/div>\n                                \n                    <\/div>\n\n    <\/section>\n\n\n<section class=\"expertise-section expertise-section--text expertise-section--dark expertise-section--text-center\">\n\n    \n        <div class=\"container\">\n                        \n            \n                                    <div class=\"expertise-section__text\">\n                        <p><strong>Successive temperature rise curves for a DECONTACTOR<sup>\u2122<\/sup> subjected to a particular current cycle<\/strong><\/p>\n                    <\/div>\n                                \n                    <\/div>\n\n    <\/section>\n\n\n<section class=\"expertise-section expertise-section--image expertise-section--dark\">\n\n    \n        <div class=\"container\">\n                        \n            \n                \n                                    <figure class=\"expertise-section__figure\">\n                        <img decoding=\"async\"\n                            src=\"https:\/\/marechal.com\/wp-content\/uploads\/2026\/08\/Groupe-4381.webp\"\n                            alt=\"\"\n                            loading=\"lazy\"\n                        >\n                                            <\/figure>\n                \n                    <\/div>\n\n    <\/section>\n\n\n<section class=\"expertise-section expertise-section--text expertise-section--dark expertise-section--text-center\">\n\n    \n        <div class=\"container\">\n                        \n            \n                                    <div class=\"expertise-section__text\">\n                        <p>The IEC\/EN 60309-1 plug socket-outlet standard limits contact temperature rise to 50 K in an ambient temperature of up to 45\u00b0C.<br \/>\nSilver alloy contacts can withstand temperatures of up to 400\u00b0C without damage, and their heating is limited by the need not to damage surrounding parts or present a danger to operators.<br \/>\nUnder the test conditions specified in IEC 60309-1, the maximum temperature increase observed for MARECHAL<sup>\u00ae<\/sup> products is less than 50 K.<\/p>\n                    <\/div>\n                                \n                    <\/div>\n\n    <\/section>\n\n\n<section class=\"cta-final cta-final--dark cta-final--has-video\">\n            <video\n            class=\"cta-final__video\"\n            autoplay muted loop playsinline preload=\"none\"\n            data-lazy-video=\"viewport\"\n            data-src=\"https:\/\/marechal.com\/wp-content\/uploads\/2026\/07\/marechal-homepage-contact-background.mp4\"\n        ><\/video>\n    \n    <div class=\"cta-final__container\">\n        <div class=\"cta-final__text\">\n                            <span class=\"cta-final__surtitle\">State-of-the-art technology<\/span>                        <h2 class=\"cta-final__title\">Choose MARECHAL ELECTRIC<\/h2>        <\/div>\n        <div class=\"cta-final__action\">\n            <a class=\"btn-arrow cta-final__btn\" href=\"\/en\/contact\">\n                <span class=\"btn-arrow__label\">CONTACT US<\/span>\n                <span class=\"btn-arrow__arrow\" aria-hidden=\"true\"><\/span>\n            <\/a>\n        <\/div>\n    <\/div>\n<\/section>\n","protected":false},"excerpt":{"rendered":"<p>Overheating is the main cause of damage to plug socket-outlets. It is linked to the comprehensive resistance of 5 contacts in set: Quality of materials The force applied to the contact Connection terminals (clamps) Capacity to withstand overloads (time constant)<\/p>\n","protected":false},"author":115,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"templates\/template-expertise.php","meta":{"_acf_changed":false,"footnotes":""},"class_list":["post-115122","page","type-page","status-publish"],"acf":[],"_links":{"self":[{"href":"https:\/\/marechal.com\/en\/wp-json\/wp\/v2\/pages\/115122","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/marechal.com\/en\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/marechal.com\/en\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/marechal.com\/en\/wp-json\/wp\/v2\/users\/115"}],"replies":[{"embeddable":true,"href":"https:\/\/marechal.com\/en\/wp-json\/wp\/v2\/comments?post=115122"}],"version-history":[{"count":5,"href":"https:\/\/marechal.com\/en\/wp-json\/wp\/v2\/pages\/115122\/revisions"}],"predecessor-version":[{"id":119503,"href":"https:\/\/marechal.com\/en\/wp-json\/wp\/v2\/pages\/115122\/revisions\/119503"}],"wp:attachment":[{"href":"https:\/\/marechal.com\/en\/wp-json\/wp\/v2\/media?parent=115122"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}