{"id":14228,"date":"2023-02-20T10:11:27","date_gmt":"2023-02-20T10:11:27","guid":{"rendered":"https:\/\/kcsensor.com\/?p=14228"},"modified":"2026-09-26T08:57:38","modified_gmt":"2026-09-26T08:57:38","slug":"influence-of-dielectric-constant-on-radar-level-meter","status":"publish","type":"post","link":"https:\/\/www.kcsensor.com\/fr\/influence-of-dielectric-constant-on-radar-level-meter\/","title":{"rendered":"Comment la constante di\u00e9lectrique affecte la mesure du niveau radar (\u03b5r Tableau &amp; Guide de s\u00e9lection)"},"content":{"rendered":"<p class=\"wp-block-paragraph\">La constante di\u00e9lectrique (permis relative,<sub>r<\/sub>) du milieu d\u00e9termine la quantit\u00e9 du signal radar r\u00e9fl\u00e9chie \u00e0 l'antenne. M\u00e9dias avec \u03b5<sub>r<\/sub> &gt; 3.6 refl\u00e8tent fortement et sont des cibles faciles;<sub>r<\/sub> les hydrocarbures (typiquement 1,4\u20134,0) ne refl\u00e8tent qu'une petite fraction du signal et n\u00e9cessitent <strong>radar \u00e0 ondes guid\u00e9es<\/strong> ou <strong>radar \u00e0 haute fr\u00e9quence (80 GHz) sans contact<\/strong> Pour une mesure fiable, l'affirmation commune selon laquelle les liquides constants di\u00e9lectriques faibles ne peuvent pas \u00eatre mesur\u00e9s par radar est donc en partie vraie \u2014 quels sont les changements que vous sp\u00e9cifiez.<\/p>\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\">Si vous n'\u00eates pas familier avec la constante di\u00e9lectrique, veuillez regarder cette vid\u00e9o pour vous aider \u00e0 comprendre les bases.<br \/><a href=\"https:\/\/www.youtube.com\/watch?v=4hpLxJYEBHA&amp;t\" target=\"_blank\" rel=\"noopener\">https:\/\/www.youtube.com\/watch?v=4hpLxJYEBHA&amp;t<\/a><\/p>\n<\/blockquote>\n<h2 class=\"wp-block-heading\"><strong>Qu'est-ce que la constante di\u00e9lectrique<sub>r<\/sub>)?<\/strong><\/h2>\n<p class=\"wp-block-paragraph\">Constante di\u00e9lectrique, plus pr\u00e9cis\u00e9ment <em>autorisation relative<\/em>, d\u00e9crit comment un mat\u00e9riau r\u00e9agit \u00e0 un champ \u00e9lectrique appliqu\u00e9: combien de charge il stocke par unit\u00e9 de tension par rapport au vide. Pour la mesure au niveau du radar, il importe pour une raison \u2014 la taille de la r\u00e9flexion \u00e0 la surface moyenne est r\u00e9gie par la <strong>contraste de la capacit\u00e9<\/strong> entre le milieu et l'air (ou la vapeur) au-dessus. Un grand contraste produit un fort \u00e9cho; un petit contraste produit un faible.<\/p>\n<p class=\"wp-block-paragraph\">Les deux extr\u00e9mit\u00e9s de l'\u00e9chelle pratique:<\/p>\n<ul class=\"wp-block-list\">\n<li><strong>\u00c9lev\u00e9<sub>r<\/sub> (polaire, conducteur):<\/strong> solutions aqueuses, acides et bases. \u03b5<sub>r<\/sub> pour l'eau est d'environ 80 \u00e0 la temp\u00e9rature ambiante, donc la surface se comporte presque comme un miroir radar.<\/li>\n<li><strong>Faible<sub>r<\/sub> (non-polaire):<\/strong> hydrocarbures, solvants et gaz liqu\u00e9fi\u00e9s. Le benz\u00e8ne est autour de 2,3 et le n-hexane autour de 1,9, donc la plupart de l'impulsion passe dans le milieu au lieu de revenir.<\/li>\n<\/ul>\n<p class=\"wp-block-paragraph\">L'industrie regroupe les m\u00e9dias en trois bandes, ce qui est un raccourci utile pour lire une feuille de sp\u00e9cifications : <strong>non polaire<\/strong> (\u03b5)<sub>r<\/sub> etlt; 2.8), <strong>faiblement polaire<\/strong> (2,8 \u2264 \u03b5)<sub>r<\/sub> \u2264 3,6), et <strong>polaire<\/strong> (\u03b5)<sub>r<\/sub> > 3.6).<\/p>\n<h2 class=\"wp-block-heading\"><strong>Type de radar di\u00e9lectrique constant et recommand\u00e9<\/strong><\/h2>\n<p class=\"wp-block-paragraph\">Tableau ci-dessous<sub>r<\/sub> valeurs avec la technologie radar qui mesure de fa\u00e7on fiable chaque milieu. Les valeurs sont la capacit\u00e9 relative \u00e0 environ 20&nbsp;\u00b0C.<\/p>\n<figure class=\"wp-block-table\">\n<table class=\"has-fixed-layout\">\n<thead>\n<tr>\n<th>Moyen<\/th>\n<th>\u03b5<sub>r<\/sub> (typique)<\/th>\n<th>M\u00e9thode de mesure recommand\u00e9e<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Eau<\/td>\n<td>80<\/td>\n<td>Radar sans contact \u2014 fort \u00e9cho, cas le plus facile<\/td>\n<\/tr>\n<tr>\n<td>Acides\/solutions caustiques (conductrices)<\/td>\n<td>40-80<\/td>\n<td>Radar sans contact avec une antenne compatible avec la corrosion (PTFE \/ bride)<\/td>\n<\/tr>\n<tr>\n<td>M\u00e9thanol, \u00e9thanol, ac\u00e9tone<\/td>\n<td>20\u201333<\/td>\n<td>radar sans contact, standard 80&nbsp;GHz<\/td>\n<\/tr>\n<tr>\n<td>Alcools et solvants<\/td>\n<td>15-25<\/td>\n<td>Radar sans contact; onde guid\u00e9e o\u00f9 l'agitation ou une buse \u00e9troite limite le faisceau<\/td>\n<\/tr>\n<tr>\n<td>Acide ac\u00e9tique<\/td>\n<td>6.2<\/td>\n<td>radar sans contact (80&nbsp;GHz recommand\u00e9)<\/td>\n<\/tr>\n<tr>\n<td>Huiles comestibles et huiles de transformation<\/td>\n<td>2-5<\/td>\n<td>80&nbsp;GHz radar sans contact, ou radar \u00e0 ondes guid\u00e9es o\u00f9 un puits de st\u00e8lement est disponible<\/td>\n<\/tr>\n<tr>\n<td>Hydrocarbures\/essence\/benz\u00e8ne<\/td>\n<td>- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -<\/td>\n<td>radar \u00e0 ondes guid\u00e9es (meilleur signal), ou radar sans contact 80&nbsp;GHz<\/td>\n<\/tr>\n<tr>\n<td>Gaz de p\u00e9trole liqu\u00e9fi\u00e9, solvant no 4<\/td>\n<td>1.4 \u00e0 1.8<\/td>\n<td>radar \u00e0 ondes guid\u00e9es seulement<\/td>\n<\/tr>\n<tr>\n<td>Poudres et mati\u00e8res solides (poussi\u00e8res)<\/td>\n<td>varie consid\u00e9rablement<\/td>\n<td>80&nbsp;GHz radar sans contact; onde guid\u00e9e si l'accumulation sur la sonde peut \u00eatre tol\u00e9r\u00e9e<\/td>\n<\/tr>\n<\/tbody>\n<\/table><figcaption class=\"wp-element-caption\">Tableau \u2014 constante di\u00e9lectrique (permis relative) et m\u00e9thode de mesure recommand\u00e9e. Valeurs \u00e0 20 \u00b0C, compil\u00e9es \u00e0 partir de tableaux de r\u00e9f\u00e9rence standard sur la propri\u00e9t\u00e9 physique (CRC Handbook of Chemistry and Physics) et de documentation technique du fabricant d'instruments. Les valeurs varient en fonction de la temp\u00e9rature, de la puret\u00e9 et de la fr\u00e9quence de mesure \u2014 confirmer par rapport \u00e0 votre fiche technique de support et de n\u00b0 8217; s avant de pr\u00e9ciser.<\/figcaption><\/figure>\n<h2 class=\"wp-block-heading\"><strong>Liquides communs et leur capacit\u00e9 relative<\/strong><\/h2>\n<p class=\"wp-block-paragraph\">Pour les travaux de r\u00e9f\u00e9rence, la liste plus longue ci-dessous couvre les solvants qui g\u00e9n\u00e8rent la plupart des enqu\u00eates de mesure de niveau. Les valeurs sont la capacit\u00e9 relative \u00e0 la temp\u00e9rature ambiante.<\/p>\n<figure class=\"wp-block-table\">\n<table class=\"has-fixed-layout\">\n<thead>\n<tr>\n<th>Liquide<\/th>\n<th>\u03b5<sub>r<\/sub><\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Eau ( H<sub>2<\/sub>O)<\/td>\n<td>78.5<\/td>\n<\/tr>\n<tr>\n<td>Acide formique (HCOOH)<\/td>\n<td>58.5<\/td>\n<\/tr>\n<tr>\n<td>N,N-dim\u00e9thylformamide (DMF)<\/td>\n<td>36.7<\/td>\n<\/tr>\n<tr>\n<td>M\u00e9thanol (CH)<sub>3<\/sub>OH)<\/td>\n<td>32.7<\/td>\n<\/tr>\n<tr>\n<td>\u00c9thanol (C)<sub>2<\/sub>H<sub>5<\/sub>OH)<\/td>\n<td>24.5<\/td>\n<\/tr>\n<tr>\n<td>Ac\u00e9tone (CH<sub>3<\/sub>COCH<sub>3<\/sub>)<\/td>\n<td>20.7<\/td>\n<\/tr>\n<tr>\n<td>n-hexanol<\/td>\n<td>13.3<\/td>\n<\/tr>\n<tr>\n<td>Acide ac\u00e9tique<\/td>\n<td>6.15<\/td>\n<\/tr>\n<tr>\n<td>Benz\u00e8ne (C<sub>6<\/sub>H<sub>6<\/sub>)<\/td>\n<td>2.28<\/td>\n<\/tr>\n<tr>\n<td>t\u00e9trachlorure de carbone (CCl)<sub>4<\/sub>)<\/td>\n<td>2.24<\/td>\n<\/tr>\n<tr>\n<td>n-hexane (C<sub>6<\/sub>H<sub>14<\/sub>)<\/td>\n<td>1.88<\/td>\n<\/tr>\n<tr>\n<td>No 4 solvant<\/td>\n<td>1.78<\/td>\n<\/tr>\n<\/tbody>\n<\/table><figcaption class=\"wp-element-caption\">Tableau \u2014 Autorisation relative des liquides communs \u00e0 temp\u00e9rature ambiante (valeurs de r\u00e9f\u00e9rence standard)<\/figcaption><\/figure>\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-3a8a1933 wp-block-columns-is-layout-flex\" style=\"padding-top:0;padding-right:0;padding-bottom:0;padding-left:0\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" data-dominant-color=\"f4f4f4\" data-has-transparency=\"true\" style=\"--dominant-color: #f4f4f4;\" decoding=\"async\" width=\"554\" height=\"675\" src=\"\/wp-content\/uploads\/2023\/02\/Commonly-Used-Dielectric-Constant-Table1.png\" alt=\"Tableau de r\u00e9f\u00e9rence des valeurs constantes relatives pour les gaz, les vapeurs et les solides\" class=\"wp-image-14229 has-transparency\" srcset=\"https:\/\/www.kcsensor.com\/wp-content\/uploads\/2023\/02\/Commonly-Used-Dielectric-Constant-Table1.png 554w, https:\/\/www.kcsensor.com\/wp-content\/uploads\/2023\/02\/Commonly-Used-Dielectric-Constant-Table1-246x300.png 246w\" sizes=\"auto, (max-width: 554px) 100vw, 554px\" \/><figcaption class=\"wp-element-caption\">Fig. 1 \u2014 Reference values: relative dielectric constant of common gases, vapours and solids.<\/figcaption><\/figure>\n<\/div>\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" data-dominant-color=\"f6f6f6\" data-has-transparency=\"true\" style=\"--dominant-color: #f6f6f6;\" decoding=\"async\" width=\"554\" height=\"386\" src=\"\/wp-content\/uploads\/2023\/02\/Commonly-Used-Dielectric-Constant-Table2.png\" alt=\"Tableau de r\u00e9f\u00e9rence des valeurs de constantes di\u00e9lectriques relatives pour les liquides et les mat\u00e9riaux solides\" class=\"wp-image-14230 has-transparency\" srcset=\"https:\/\/www.kcsensor.com\/wp-content\/uploads\/2023\/02\/Commonly-Used-Dielectric-Constant-Table2.png 554w, https:\/\/www.kcsensor.com\/wp-content\/uploads\/2023\/02\/Commonly-Used-Dielectric-Constant-Table2-300x209.png 300w\" sizes=\"auto, (max-width: 554px) 100vw, 554px\" \/><figcaption class=\"wp-element-caption\">Fig. 2 \u2014 Reference values continued: relative dielectric constant of liquids and solid materials.<\/figcaption><\/figure>\n<\/div>\n<\/div>\n<h2 class=\"wp-block-heading\"><strong>Comment<sub>r<\/sub> Atteint le radar \u00e0 voile guid\u00e9e<\/strong><\/h2>\n<p class=\"wp-block-paragraph\">Le radar \u00e0 ondes guid\u00e9es envoie une impulsion basse \u00e9nergie vers le bas d'une sonde (c\u00e2ble d'acier ou tige). \u00c0 la limite de la sonde\/moyen, la variation de la constante di\u00e9lectrique refl\u00e8te une partie de l'impulsion; le reste continue vers le bas de la sonde. Parce que l'impulsion est guid\u00e9e plut\u00f4t que rayonn\u00e9e, l'\u00e9cho ne d\u00e9pend pas d'une surface plane ou d'un large faisceau \u2014 c'est pourquoi l'onde guid\u00e9e fait face \u00e0 la turbulence, aux surfaces inclin\u00e9es et \u00e0 une tr\u00e8s faible \u03b5<sub>r<\/sub> les m\u00e9dias qui d\u00e9fait une unit\u00e9 sans contact.<\/p>\n<p class=\"wp-block-paragraph\">Bandes pratiques pour la s\u00e9lection des ondes guid\u00e9es :<\/p>\n<ul class=\"wp-block-list\">\n<li>Produits p\u00e9troliers et hydrocarbures dans le service p\u00e9trochimique: 1,4 \u2264 \u03b5<sub>r<\/sub> \u2264 4,0<\/li>\n<li>Alcools, solvants organiques et m\u00e9langes huile-eau: 4,0 \u2264 \u03b5<sub>r<\/sub> \u2264 10,0<\/li>\n<li>Liquides conducteurs tels que solutions aqueuses, acides dilu\u00e9s et bases:<sub>r<\/sub> > 10.0<\/li>\n<\/ul>\n<p class=\"wp-block-paragraph\">Le radar \u00e0 ondes guid\u00e9es peut \u00e9galement mesurer une interface gaz\/liquide, gaz\/solide ou liquide\/liquide, qui est la solution standard pour la d\u00e9tection des limites de l'eau-p\u00e9trole dans les s\u00e9parateurs et les puisards.<\/p>\n<h2 class=\"wp-block-heading\"><strong>Comment<sub>r<\/sub> Effets sur le radar sans contact<\/strong><\/h2>\n<div class=\"wp-block-columns is-layout-flex wp-container-core-columns-is-layout-3a8a1933 wp-block-columns-is-layout-flex\" style=\"padding-top:0;padding-right:0;padding-bottom:0;padding-left:0\">\n<div class=\"wp-block-column is-vertically-aligned-center is-layout-flow wp-block-column-is-layout-flow\">\n<p class=\"wp-block-paragraph\">Le radar sans contact rayonne d'une antenne et repose sur la r\u00e9flexion de la surface du produit. Plus la constante di\u00e9lectrique est \u00e9lev\u00e9e, plus la r\u00e9flexion est forte \u2014 et, tout le reste \u00e9tant \u00e9gal, plus la port\u00e9e est longue. Plus la cible est grande, plus le signal est perdu \u00e0 la propagation du faisceau et l'att\u00e9nuation, donc un faible-\u03b5<sub>r<\/sub> support doit \u00eatre plus proche de l'antenne pour la m\u00eame fiabilit\u00e9.<br \/>Le radar moderne \u00e0 80 GHz (millim\u00e8tres-ondes) r\u00e9sout en grande partie la limite historique : une plage de signaux dynamiques beaucoup plus grande et un faisceau moyen plus \u00e9troit et plus concentr\u00e9 peuvent \u00eatre mesur\u00e9s de fa\u00e7on plus stable qu'avec les anciens instruments \u00e0 26 GHz. Notre gamme de capteurs de niveau radar de 80 GHz est sp\u00e9cifi\u00e9e pour exactement cette fonction \u2014 par exemple, le capteur de niveau radar KLD804 atteint une pr\u00e9cision de \u00b12 mm avec une zone aveugle minimale de 0,05 m, et est explicitement con\u00e7u pour maintenir la mesure sur des milieux \u00e0 basse constante di\u00e9lectrique, l'adh\u00e9rence et la condensation.<\/p>\n<\/div>\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\">\n<figure class=\"wp-block-image size-full is-resized\"><img loading=\"lazy\" data-dominant-color=\"dfe1e1\" data-has-transparency=\"false\" decoding=\"async\" width=\"500\" height=\"500\" src=\"https:\/\/www.kcsensor.com\/wp-content\/uploads\/2023\/02\/Influence-of-Dielectric-Constant-on-Radar-Level-Meter-1-jpg.webp\" alt=\"Influence de la constante di\u00e9lectrique sur le radar\" class=\"wp-image-17192 not-transparent\" style=\"--dominant-color: #dfe1e1; width:367px;height:auto\" srcset=\"https:\/\/www.kcsensor.com\/wp-content\/uploads\/2023\/02\/Influence-of-Dielectric-Constant-on-Radar-Level-Meter-1-jpg.webp 500w, https:\/\/www.kcsensor.com\/wp-content\/uploads\/2023\/02\/Influence-of-Dielectric-Constant-on-Radar-Level-Meter-1-300x300.webp 300w, https:\/\/www.kcsensor.com\/wp-content\/uploads\/2023\/02\/Influence-of-Dielectric-Constant-on-Radar-Level-Meter-1-150x150.webp 150w, https:\/\/www.kcsensor.com\/wp-content\/uploads\/2023\/02\/Influence-of-Dielectric-Constant-on-Radar-Level-Meter-1-100x100.webp 100w\" sizes=\"auto, (max-width: 500px) 100vw, 500px\" \/><\/figure>\n<\/div>\n<\/div>\n<h2 class=\"wp-block-heading\"><strong>Mesure de faible valeur<sub>r<\/sub> M\u00e9dias<sub>r<\/sub> &lt; 2.5): 80&nbsp;GHz vs Guid\u00e9 Wave<\/strong><\/h2>\n<p class=\"wp-block-paragraph\">En dessous<sub>r<\/sub> = 2,5, la r\u00e9flexion est suffisamment faible que le choix de l'instrument cesse d'\u00eatre une pr\u00e9f\u00e9rence et devient une contrainte. Les deux options viables ont des limites diff\u00e9rentes :<\/p>\n<figure class=\"wp-block-table\">\n<table class=\"has-fixed-layout\">\n<thead>\n<tr>\n<th>Situation<\/th>\n<th>Choisissez<\/th>\n<th>Pourquoi<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>\u03b5<sub>r<\/sub> 1.8-2.5, liquide propre, grande buse, aucune accumulation sur une sonde<\/td>\n<td>80&nbsp;GHz radar sans contact<\/td>\n<td>La plage dynamique d'onde millim\u00e9trique r\u00e9cup\u00e8re l'\u00e9cho faible; rien ne contacte le produit<\/td>\n<\/tr>\n<tr>\n<td>\u03b5<sub>r<\/sub> 1.4\u20131.8, ou une chambre de puits\/de contournement est disponible<\/td>\n<td>radar \u00e0 ondes guid\u00e9es<\/td>\n<td>Le pouls est guid\u00e9 le long de la sonde, donc la perte de chemin est minime et la faible r\u00e9flexion est encore d\u00e9celable<\/td>\n<\/tr>\n<tr>\n<td>Surface turbulente, mousse ou niveau liquide fortement inclin\u00e9<\/td>\n<td>radar \u00e0 ondes guid\u00e9es<\/td>\n<td>L'\u00e9cho ne d\u00e9pend pas d'une surface plane et horizontale<\/td>\n<\/tr>\n<tr>\n<td>Support agressif, service d'hygi\u00e8ne ou accumulation qui pourrait endommager une sonde<\/td>\n<td>80&nbsp;GHz radar sans contact<\/td>\n<td>Pas de sonde mouill\u00e9e pour nettoyer ou corroder<\/td>\n<\/tr>\n<tr>\n<td>Interface liquide\/liquide (huile\u2013eau)<\/td>\n<td>radar \u00e0 ondes guid\u00e9es<\/td>\n<td>R\u00e9sout la r\u00e9flexion d'interface, pas seulement la surface sup\u00e9rieure<\/td>\n<\/tr>\n<tr>\n<td>Grand silo avec des solides poussi\u00e9reux, tr\u00e8s longue port\u00e9e<\/td>\n<td>80&nbsp;GHz radar sans contact<\/td>\n<td>Poutre \u00e9troite et plage dynamique \u00e9lev\u00e9e, non affect\u00e9e par la poussi\u00e8re et la condensation<\/td>\n<\/tr>\n<\/tbody>\n<\/table><figcaption class=\"wp-element-caption\">Tableau \u2014 Limites de s\u00e9lection des milieux \u00e0 constante di\u00e9lectrique basse<\/figcaption><\/figure>\n<p class=\"wp-block-paragraph\">Lorsqu'un r\u00e9servoir n'a pas de buse adapt\u00e9e pour un radar sans contact de 80 nbsp;GHz ni de puits fixe pour une sonde, l'alternative pratique consiste \u00e0 modifier compl\u00e8tement le principe de mesure plut\u00f4t que d'accepter une lecture radar peu fiable \u2014 un instrument capacitif ou hydrostatique peut \u00eatre la r\u00e9ponse technique correcte.<\/p>\n<h2 class=\"wp-block-heading\"><strong>Mesure de l'interface: Quoi \u03b5<sub>r<\/sub> N\u00e9cessite<\/strong><\/h2>\n<p class=\"wp-block-paragraph\">Le radar \u00e0 ondes guid\u00e9es et le radar sans contact peuvent mesurer une interface en suivant la partie de l'impulsion qui n'est pas r\u00e9fl\u00e9chie \u00e0 la surface sup\u00e9rieure jusqu'au produit inf\u00e9rieur. Les exigences sont plus strictes que pour le niveau simple:<\/p>\n<ul class=\"wp-block-list\">\n<li><strong>radar \u00e0 ondes guid\u00e9es:<\/strong> le milieu sup\u00e9rieur doit g\u00e9n\u00e9ralement avoir une \u00e9paisseur d'au moins 10 \u00e0 20 cm pour que les deux \u00e9chos puissent \u00eatre r\u00e9solus; le milieu sup\u00e9rieur \u03b5<sub>r<\/sub> devrait \u00eatre inf\u00e9rieure \u00e0 3 et inf\u00e9rieure \u00e0 20, avec une diff\u00e9rence sup\u00e9rieure \u00e0 10.<\/li>\n<li><strong>radar sans contact:<\/strong> les constantes di\u00e9lectriques des deux produits doivent \u00eatre connues et stables, et la diff\u00e9rence entre elles doit \u00eatre sup\u00e9rieure \u00e0 environ 6.<\/li>\n<li>Dans les deux cas, la mesure se d\u00e9grade si la couche sup\u00e9rieure est \u00e9mulsifi\u00e9e, si son \u00e9paisseur varie rapidement, ou si la mousse se trouve \u00e0 l'une ou l'autre des limites.<\/li>\n<\/ul>\n<h2 class=\"wp-block-heading\"><strong>Choisir le bon radar pour votre liquide<\/strong><\/h2>\n<p class=\"wp-block-paragraph\">Un bref r\u00e9sum\u00e9 de s\u00e9lection: l'eau et les solutions aqueuses sont le cas facile \u2014 le radar standard sans contact les g\u00e8re. Solvants et huiles l\u00e9g\u00e8res s'assoient dans la bande m\u00e9diane et veulent g\u00e9n\u00e9ralement 80&nbsp;GHz. Les hydrocarbures et les gaz liqu\u00e9fi\u00e9s sont le cas dur et veulent g\u00e9n\u00e9ralement une onde guid\u00e9e. Si votre r\u00e9servoir est \u00e0 distance et le c\u00e2blage est la contrainte plut\u00f4t que le support, un syst\u00e8me radar sans fil change l'\u00e9conomie de l'installation \u2014 voir notre <a href=\"\/fr\/433m-wireless-radar-technical-solution\/\" rel=\"noreferrer noopener\">433&nbsp;M solution technique radar sans fil<\/a>, et pour la comparaison t\u00eate \u00e0 t\u00eate entre les deux technologies lire <a href=\"\/fr\/80g-radar-vs-guided-wave-radar-which-one-has-the-advantage\/\" rel=\"noreferrer noopener\">radar de 80&nbsp;GHz contre radar \u00e0 ondes guid\u00e9es<\/a>. Le catalogue complet se trouve sous <a href=\"\/fr\/product-category\/radar-level-sensor\/\" rel=\"noreferrer noopener\">capteurs de niveau radar<\/a>, avec des mod\u00e8les \u00e0 ondes guid\u00e9es dans un <a href=\"\/fr\/product-category\/radar-level-sensor\/guided-wave-radar\/\" rel=\"noreferrer noopener\">cat\u00e9gorie d\u00e9di\u00e9e<\/a>.<\/p>\n<h2 class=\"wp-block-heading\"><strong>FAQ<\/strong><\/h2>\n<div class=\"wp-block-group is-layout-flow wp-container-core-group-is-layout-17f477d5 wp-block-group-is-layout-flow\" style=\"padding-top:0;padding-right:0;padding-bottom:0;padding-left:0\">\n<div class=\"wp-block-group is-nowrap is-layout-flex wp-container-core-group-is-layout-b7d9c19b wp-block-group-is-layout-flex\" style=\"margin-top:0;margin-bottom:0;padding-top:0;padding-right:0;padding-bottom:0;padding-left:0\">\n<div class=\"wp-block-safe-svg-svg-icon safe-svg-cover\" style=\"text-align: left;\">\n<div class=\"safe-svg-inside safe-svg-inline\" style=\"width: 32px; height: 32px; background-color: var(--wp--preset--color--); color: var(--wp--preset--color--); padding-top: ; padding-right: ; padding-bottom: ; padding-left: ; margin-top: ; margin-right: ; margin-bottom: ; margin-left: ;\"><?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?> <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" class=\"icon\" viewbox=\"0 0 1024 1024\" version=\"1.1\" width=\"32\" height=\"32\"><path d=\"M358.70592 758.7456c-33.01888-30.9504-54.48448-68.19072-64.29056-111.7952-11.46752-50.99264-3.54176-99.89632 18.03264-146.9696 17.74592-38.71744 42.84416-72.6208 69.29024-105.6384 28.12416-35.1104 57.45792-69.28384 82.5088-106.77248 15.18592-22.7264 29.34016-46.01984 39.91552-71.3216 0.4928-1.1776 1.05856-2.33216 1.68064-3.44704 1.70624-3.05152 4.27008-4.57856 7.83872-4.57472 3.72224 0.00384 6.03648 1.98784 7.38048 5.14048 24.1536 56.64384 61.8368 104.25728 100.50816 151.27936 27.07712 32.92416 54.592 65.536 76.032 102.6944 17.06496 29.57568 30.71488 60.416 36.49408 94.25536 10.65856 62.4064-3.3728 119.11936-41.35808 169.50016-37.87136 50.22848-89.12384 79.04768-151.0592 86.68288-69.376 8.55424-130.6048-11.64928-182.97344-59.0336m234.77248-308.38784c-4.71168-6.65984-10.2016-12.57728-16.7936-17.41824-27.78368-20.40832-58.83648-24.52736-91.15392-15.51872-30.048 8.37376-52.27264 26.62144-60.46464 58.32832-3.8144 14.76096 11.6224 29.66528 26.5024 26.29632 10.26304-2.32448 15.936-9.09952 19.61472-18.3296 5.1968-13.0496 14.19776-22.25408 27.95136-25.984 7.39456-2.00576 14.9824-1.72672 22.71232-1.472 20.41088 0.672 41.17248 19.92576 34.42432 48.6016-2.8928 12.2944-11.34976 20.73344-19.96032 29.07392-9.1776 8.8896-19.29088 16.81408-27.35744 26.84928-10.16704 12.65024-16.73984 26.74816-16.91904 43.2064-0.1408 13.03552 7.54816 21.3248 20.28928 22.65344 12.3136 1.28256 20.4096-4.6528 22.51136-18.00192 2.26432-14.37952 9.792-25.08672 20.4608-34.2912 8.55168-7.37664 16.9856-14.91968 25.09824-22.77376 29.64992-28.70272 34.8224-67.61216 13.08416-101.21984M546.4448 689.152c3.58912-15.9744-8.8192-34.05568-25.41568-37.0368-18.91072-3.39584-37.376 9.43616-39.45856 27.424-1.87008 16.13824 10.0352 32.6208 25.66784 35.53536 17.69728 3.29984 34.2528-7.27168 39.2064-25.92256z\" fill=\"#d81e06\"><\/path><\/svg> <\/div>\n<\/p><\/div>\n<p class=\"wp-block-paragraph\"><strong>Q: Quelle est la constante di\u00e9lectrique minimale qu'un radar sans contact peut mesurer?<\/strong><\/p>\n<\/div>\n<div class=\"wp-block-group is-nowrap is-layout-flex wp-container-core-group-is-layout-b7d9c19b wp-block-group-is-layout-flex\" style=\"margin-top:0;margin-bottom:0;padding-top:0;padding-right:0;padding-bottom:0;padding-left:0\">\n<div class=\"wp-block-safe-svg-svg-icon safe-svg-cover\" style=\"text-align: left;\">\n<div class=\"safe-svg-inside safe-svg-inline\" style=\"width: 32px; height: 32px; background-color: var(--wp--preset--color--); color: var(--wp--preset--color--); padding-top: 0; padding-right: 0; padding-bottom: 0; padding-left: 0; margin-top: 0; margin-right: 0; margin-bottom: 0; margin-left: 0;\"><?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?> <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" class=\"icon\" viewbox=\"0 0 1024 1024\" version=\"1.1\" width=\"32\" height=\"32\"><path d=\"M501.0496 225.9008c1.9776-4.30848 3.3792-8.41984 5.65248-11.9744 3.82464-5.98656 11.03232-5.89184 13.73056 0.51968 27.92704 66.35136 74.78016 119.73888 119.27424 174.7456 25.23776 31.20128 49.71008 62.8992 68.15104 98.80448 17.57952 34.2272 28.4416 70.3424 29.28128 108.89088 0.8832 40.52608-9.22368 78.46144-30.06976 113.39008-32.99328 55.27936-80.94464 90.8096-143.59424 104.55296-76.60288 16.80256-145.1776-1.41696-203.41376-54.08384-39.3472-35.584-62.4128-80.41984-68.70272-133.44512-6.31808-53.26336 6.912-102.2336 32.6464-148.46336 21.2736-38.2208 48.8768-71.87584 76.31104-105.62432 32.3008-39.73248 64.4672-79.53536 89.2032-124.6592 3.9936-7.28576 7.57376-14.79808 11.53024-22.65344m-36.41216 378.90304c-15.41376-15.35232-30.78784-30.7456-46.26176-46.03648-6.16832-6.09536-10.1184-6.1056-16.38016-0.01024a1031.35872 1031.35872 0 0 0-22.57792 22.6496c-6.88768 7.13344-6.80448 9.34144 0.13696 16.43136 16.2624 16.6144 32.58112 33.17248 48.8448 49.78432 13.8752 14.17216 27.62752 28.46336 41.58464 42.55104 6.6816 6.7456 11.33696 6.4768 17.856-0.44032 1.16992-1.2416 2.26432-2.55232 3.38816-3.83616 40.47488-46.19008 80.93952-92.3904 121.43104-138.5664 12.512-14.26944 25.09056-28.48 37.664-42.69568 3.30496-3.7376 5.07136-7.7952 1.09696-11.89504-8.45696-8.72704-17.0624-17.3184-25.85088-25.71008-3.54688-3.38688-7.74016-3.2768-11.52256 0.06784-2.0736 1.83296-4.1024 3.73504-5.9776 5.7664-16.48256 17.85728-32.98944 35.69536-49.36704 53.64864-23.70688 25.98528-47.32544 52.0512-70.9568 78.1056-13.6 14.99648-9.64224 12.96512-23.10784 0.1856z\" fill=\"#21a529\"><\/path><\/svg> <\/div>\n<\/p><\/div>\n<p class=\"wp-block-paragraph\"><strong>A :<\/strong> Les fabricants sp\u00e9cifient g\u00e9n\u00e9ralement un minimum d'environ<sub>r<\/sub> 1.5\u20132 pour radar sans contact. Au-dessous de cela, le radar \u00e0 ondes guid\u00e9es est la technologie recommand\u00e9e, car l'impulsion est guid\u00e9e le long d'une sonde plut\u00f4t que par l'air.<\/p>\n<\/div>\n<div class=\"wp-block-group is-nowrap is-layout-flex wp-container-core-group-is-layout-b7d9c19b wp-block-group-is-layout-flex\" style=\"margin-top:0;margin-bottom:0;padding-top:0;padding-right:0;padding-bottom:0;padding-left:0\">\n<div class=\"wp-block-safe-svg-svg-icon safe-svg-cover\" style=\"text-align: left;\">\n<div class=\"safe-svg-inside safe-svg-inline\" style=\"width: 32px; height: 32px; background-color: var(--wp--preset--color--); color: var(--wp--preset--color--); padding-top: ; padding-right: ; padding-bottom: ; padding-left: ; margin-top: ; margin-right: ; margin-bottom: ; margin-left: ;\"><?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?> <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" class=\"icon\" viewbox=\"0 0 1024 1024\" version=\"1.1\" width=\"32\" height=\"32\"><path d=\"M358.70592 758.7456c-33.01888-30.9504-54.48448-68.19072-64.29056-111.7952-11.46752-50.99264-3.54176-99.89632 18.03264-146.9696 17.74592-38.71744 42.84416-72.6208 69.29024-105.6384 28.12416-35.1104 57.45792-69.28384 82.5088-106.77248 15.18592-22.7264 29.34016-46.01984 39.91552-71.3216 0.4928-1.1776 1.05856-2.33216 1.68064-3.44704 1.70624-3.05152 4.27008-4.57856 7.83872-4.57472 3.72224 0.00384 6.03648 1.98784 7.38048 5.14048 24.1536 56.64384 61.8368 104.25728 100.50816 151.27936 27.07712 32.92416 54.592 65.536 76.032 102.6944 17.06496 29.57568 30.71488 60.416 36.49408 94.25536 10.65856 62.4064-3.3728 119.11936-41.35808 169.50016-37.87136 50.22848-89.12384 79.04768-151.0592 86.68288-69.376 8.55424-130.6048-11.64928-182.97344-59.0336m234.77248-308.38784c-4.71168-6.65984-10.2016-12.57728-16.7936-17.41824-27.78368-20.40832-58.83648-24.52736-91.15392-15.51872-30.048 8.37376-52.27264 26.62144-60.46464 58.32832-3.8144 14.76096 11.6224 29.66528 26.5024 26.29632 10.26304-2.32448 15.936-9.09952 19.61472-18.3296 5.1968-13.0496 14.19776-22.25408 27.95136-25.984 7.39456-2.00576 14.9824-1.72672 22.71232-1.472 20.41088 0.672 41.17248 19.92576 34.42432 48.6016-2.8928 12.2944-11.34976 20.73344-19.96032 29.07392-9.1776 8.8896-19.29088 16.81408-27.35744 26.84928-10.16704 12.65024-16.73984 26.74816-16.91904 43.2064-0.1408 13.03552 7.54816 21.3248 20.28928 22.65344 12.3136 1.28256 20.4096-4.6528 22.51136-18.00192 2.26432-14.37952 9.792-25.08672 20.4608-34.2912 8.55168-7.37664 16.9856-14.91968 25.09824-22.77376 29.64992-28.70272 34.8224-67.61216 13.08416-101.21984M546.4448 689.152c3.58912-15.9744-8.8192-34.05568-25.41568-37.0368-18.91072-3.39584-37.376 9.43616-39.45856 27.424-1.87008 16.13824 10.0352 32.6208 25.66784 35.53536 17.69728 3.29984 34.2528-7.27168 39.2064-25.92256z\" fill=\"#d81e06\"><\/path><\/svg> <\/div>\n<\/p><\/div>\n<p class=\"wp-block-paragraph\"><strong>Q: Quelle diff\u00e9rence de constante di\u00e9lectrique est n\u00e9cessaire pour la mesure de l'interface huile-eau?<\/strong><\/p>\n<\/div>\n<div class=\"wp-block-group is-nowrap is-layout-flex wp-container-core-group-is-layout-b7d9c19b wp-block-group-is-layout-flex\" style=\"margin-top:0;margin-bottom:0;padding-top:0;padding-right:0;padding-bottom:0;padding-left:0\">\n<div class=\"wp-block-safe-svg-svg-icon safe-svg-cover\" style=\"text-align: left;\">\n<div class=\"safe-svg-inside safe-svg-inline\" style=\"width: 32px; height: 32px; background-color: var(--wp--preset--color--); color: var(--wp--preset--color--); padding-top: 0; padding-right: 0; padding-bottom: 0; padding-left: 0; margin-top: 0; margin-right: 0; margin-bottom: 0; margin-left: 0;\"><?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?> <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" class=\"icon\" viewbox=\"0 0 1024 1024\" version=\"1.1\" width=\"32\" height=\"32\"><path d=\"M501.0496 225.9008c1.9776-4.30848 3.3792-8.41984 5.65248-11.9744 3.82464-5.98656 11.03232-5.89184 13.73056 0.51968 27.92704 66.35136 74.78016 119.73888 119.27424 174.7456 25.23776 31.20128 49.71008 62.8992 68.15104 98.80448 17.57952 34.2272 28.4416 70.3424 29.28128 108.89088 0.8832 40.52608-9.22368 78.46144-30.06976 113.39008-32.99328 55.27936-80.94464 90.8096-143.59424 104.55296-76.60288 16.80256-145.1776-1.41696-203.41376-54.08384-39.3472-35.584-62.4128-80.41984-68.70272-133.44512-6.31808-53.26336 6.912-102.2336 32.6464-148.46336 21.2736-38.2208 48.8768-71.87584 76.31104-105.62432 32.3008-39.73248 64.4672-79.53536 89.2032-124.6592 3.9936-7.28576 7.57376-14.79808 11.53024-22.65344m-36.41216 378.90304c-15.41376-15.35232-30.78784-30.7456-46.26176-46.03648-6.16832-6.09536-10.1184-6.1056-16.38016-0.01024a1031.35872 1031.35872 0 0 0-22.57792 22.6496c-6.88768 7.13344-6.80448 9.34144 0.13696 16.43136 16.2624 16.6144 32.58112 33.17248 48.8448 49.78432 13.8752 14.17216 27.62752 28.46336 41.58464 42.55104 6.6816 6.7456 11.33696 6.4768 17.856-0.44032 1.16992-1.2416 2.26432-2.55232 3.38816-3.83616 40.47488-46.19008 80.93952-92.3904 121.43104-138.5664 12.512-14.26944 25.09056-28.48 37.664-42.69568 3.30496-3.7376 5.07136-7.7952 1.09696-11.89504-8.45696-8.72704-17.0624-17.3184-25.85088-25.71008-3.54688-3.38688-7.74016-3.2768-11.52256 0.06784-2.0736 1.83296-4.1024 3.73504-5.9776 5.7664-16.48256 17.85728-32.98944 35.69536-49.36704 53.64864-23.70688 25.98528-47.32544 52.0512-70.9568 78.1056-13.6 14.99648-9.64224 12.96512-23.10784 0.1856z\" fill=\"#21a529\"><\/path><\/svg> <\/div>\n<\/p><\/div>\n<p class=\"wp-block-paragraph\"><strong>A :<\/strong> Le radar \u00e0 ondes guid\u00e9es a g\u00e9n\u00e9ralement besoin du milieu sup\u00e9rieur en dessous d'environ \u03b5<sub>r<\/sub> 3 et le plus bas au-dessus d'environ 20, avec une diff\u00e9rence sup\u00e9rieure \u00e0 10; radar sans contact n\u00e9cessite une diff\u00e9rence sup\u00e9rieure \u00e0 environ 6. Les deux milieux doivent avoir connu des constantes di\u00e9lectriques stables.<\/p>\n<\/div>\n<div class=\"wp-block-group is-nowrap is-layout-flex wp-container-core-group-is-layout-b7d9c19b wp-block-group-is-layout-flex\" style=\"margin-top:0;margin-bottom:0;padding-top:0;padding-right:0;padding-bottom:0;padding-left:0\">\n<div class=\"wp-block-safe-svg-svg-icon safe-svg-cover\" style=\"text-align: left;\">\n<div class=\"safe-svg-inside safe-svg-inline\" style=\"width: 32px; height: 32px; background-color: var(--wp--preset--color--); color: var(--wp--preset--color--); padding-top: ; padding-right: ; padding-bottom: ; padding-left: ; margin-top: ; margin-right: ; margin-bottom: ; margin-left: ;\"><?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?> <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" class=\"icon\" viewbox=\"0 0 1024 1024\" version=\"1.1\" width=\"32\" height=\"32\"><path d=\"M358.70592 758.7456c-33.01888-30.9504-54.48448-68.19072-64.29056-111.7952-11.46752-50.99264-3.54176-99.89632 18.03264-146.9696 17.74592-38.71744 42.84416-72.6208 69.29024-105.6384 28.12416-35.1104 57.45792-69.28384 82.5088-106.77248 15.18592-22.7264 29.34016-46.01984 39.91552-71.3216 0.4928-1.1776 1.05856-2.33216 1.68064-3.44704 1.70624-3.05152 4.27008-4.57856 7.83872-4.57472 3.72224 0.00384 6.03648 1.98784 7.38048 5.14048 24.1536 56.64384 61.8368 104.25728 100.50816 151.27936 27.07712 32.92416 54.592 65.536 76.032 102.6944 17.06496 29.57568 30.71488 60.416 36.49408 94.25536 10.65856 62.4064-3.3728 119.11936-41.35808 169.50016-37.87136 50.22848-89.12384 79.04768-151.0592 86.68288-69.376 8.55424-130.6048-11.64928-182.97344-59.0336m234.77248-308.38784c-4.71168-6.65984-10.2016-12.57728-16.7936-17.41824-27.78368-20.40832-58.83648-24.52736-91.15392-15.51872-30.048 8.37376-52.27264 26.62144-60.46464 58.32832-3.8144 14.76096 11.6224 29.66528 26.5024 26.29632 10.26304-2.32448 15.936-9.09952 19.61472-18.3296 5.1968-13.0496 14.19776-22.25408 27.95136-25.984 7.39456-2.00576 14.9824-1.72672 22.71232-1.472 20.41088 0.672 41.17248 19.92576 34.42432 48.6016-2.8928 12.2944-11.34976 20.73344-19.96032 29.07392-9.1776 8.8896-19.29088 16.81408-27.35744 26.84928-10.16704 12.65024-16.73984 26.74816-16.91904 43.2064-0.1408 13.03552 7.54816 21.3248 20.28928 22.65344 12.3136 1.28256 20.4096-4.6528 22.51136-18.00192 2.26432-14.37952 9.792-25.08672 20.4608-34.2912 8.55168-7.37664 16.9856-14.91968 25.09824-22.77376 29.64992-28.70272 34.8224-67.61216 13.08416-101.21984M546.4448 689.152c3.58912-15.9744-8.8192-34.05568-25.41568-37.0368-18.91072-3.39584-37.376 9.43616-39.45856 27.424-1.87008 16.13824 10.0352 32.6208 25.66784 35.53536 17.69728 3.29984 34.2528-7.27168 39.2064-25.92256z\" fill=\"#d81e06\"><\/path><\/svg> <\/div>\n<\/p><\/div>\n<p class=\"wp-block-paragraph\"><strong>Q: La mousse affecte-t-elle la mesure du niveau radar sur les liquides \u00e0 faible teneur en fer?<\/strong><\/p>\n<\/div>\n<div class=\"wp-block-group is-nowrap is-layout-flex wp-container-core-group-is-layout-b7d9c19b wp-block-group-is-layout-flex\" style=\"margin-top:0;margin-bottom:0;padding-top:0;padding-right:0;padding-bottom:0;padding-left:0\">\n<div class=\"wp-block-safe-svg-svg-icon safe-svg-cover\" style=\"text-align: left;\">\n<div class=\"safe-svg-inside safe-svg-inline\" style=\"width: 32px; height: 32px; background-color: var(--wp--preset--color--); color: var(--wp--preset--color--); padding-top: 0; padding-right: 0; padding-bottom: 0; padding-left: 0; margin-top: 0; margin-right: 0; margin-bottom: 0; margin-left: 0;\"><?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?> <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" class=\"icon\" viewbox=\"0 0 1024 1024\" version=\"1.1\" width=\"32\" height=\"32\"><path d=\"M501.0496 225.9008c1.9776-4.30848 3.3792-8.41984 5.65248-11.9744 3.82464-5.98656 11.03232-5.89184 13.73056 0.51968 27.92704 66.35136 74.78016 119.73888 119.27424 174.7456 25.23776 31.20128 49.71008 62.8992 68.15104 98.80448 17.57952 34.2272 28.4416 70.3424 29.28128 108.89088 0.8832 40.52608-9.22368 78.46144-30.06976 113.39008-32.99328 55.27936-80.94464 90.8096-143.59424 104.55296-76.60288 16.80256-145.1776-1.41696-203.41376-54.08384-39.3472-35.584-62.4128-80.41984-68.70272-133.44512-6.31808-53.26336 6.912-102.2336 32.6464-148.46336 21.2736-38.2208 48.8768-71.87584 76.31104-105.62432 32.3008-39.73248 64.4672-79.53536 89.2032-124.6592 3.9936-7.28576 7.57376-14.79808 11.53024-22.65344m-36.41216 378.90304c-15.41376-15.35232-30.78784-30.7456-46.26176-46.03648-6.16832-6.09536-10.1184-6.1056-16.38016-0.01024a1031.35872 1031.35872 0 0 0-22.57792 22.6496c-6.88768 7.13344-6.80448 9.34144 0.13696 16.43136 16.2624 16.6144 32.58112 33.17248 48.8448 49.78432 13.8752 14.17216 27.62752 28.46336 41.58464 42.55104 6.6816 6.7456 11.33696 6.4768 17.856-0.44032 1.16992-1.2416 2.26432-2.55232 3.38816-3.83616 40.47488-46.19008 80.93952-92.3904 121.43104-138.5664 12.512-14.26944 25.09056-28.48 37.664-42.69568 3.30496-3.7376 5.07136-7.7952 1.09696-11.89504-8.45696-8.72704-17.0624-17.3184-25.85088-25.71008-3.54688-3.38688-7.74016-3.2768-11.52256 0.06784-2.0736 1.83296-4.1024 3.73504-5.9776 5.7664-16.48256 17.85728-32.98944 35.69536-49.36704 53.64864-23.70688 25.98528-47.32544 52.0512-70.9568 78.1056-13.6 14.99648-9.64224 12.96512-23.10784 0.1856z\" fill=\"#21a529\"><\/path><\/svg> <\/div>\n<\/p><\/div>\n<p class=\"wp-block-paragraph\"><strong>A :<\/strong> Oui. La mousse ajoute une seconde couche r\u00e9fl\u00e9chissante diffuse et att\u00e9nue le signal avant qu'il n'atteigne la surface r\u00e9elle. Sur faible<sub>r<\/sub> La marge est d\u00e9j\u00e0 mince, donc le radar \u00e0 ondes guid\u00e9es \u2014 dont l'\u00e9cho ne d\u00e9pend pas d'une surface plate \u2014 est normalement le choix le plus s\u00fbr.<\/p>\n<\/div>\n<div class=\"wp-block-group is-nowrap is-layout-flex wp-container-core-group-is-layout-b7d9c19b wp-block-group-is-layout-flex\" style=\"margin-top:0;margin-bottom:0;padding-top:0;padding-right:0;padding-bottom:0;padding-left:0\">\n<div class=\"wp-block-safe-svg-svg-icon safe-svg-cover\" style=\"text-align: left;\">\n<div class=\"safe-svg-inside safe-svg-inline\" style=\"width: 32px; height: 32px; background-color: var(--wp--preset--color--); color: var(--wp--preset--color--); padding-top: ; padding-right: ; padding-bottom: ; padding-left: ; margin-top: ; margin-right: ; margin-bottom: ; margin-left: ;\"><?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?> <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" class=\"icon\" viewbox=\"0 0 1024 1024\" version=\"1.1\" width=\"32\" height=\"32\"><path d=\"M358.70592 758.7456c-33.01888-30.9504-54.48448-68.19072-64.29056-111.7952-11.46752-50.99264-3.54176-99.89632 18.03264-146.9696 17.74592-38.71744 42.84416-72.6208 69.29024-105.6384 28.12416-35.1104 57.45792-69.28384 82.5088-106.77248 15.18592-22.7264 29.34016-46.01984 39.91552-71.3216 0.4928-1.1776 1.05856-2.33216 1.68064-3.44704 1.70624-3.05152 4.27008-4.57856 7.83872-4.57472 3.72224 0.00384 6.03648 1.98784 7.38048 5.14048 24.1536 56.64384 61.8368 104.25728 100.50816 151.27936 27.07712 32.92416 54.592 65.536 76.032 102.6944 17.06496 29.57568 30.71488 60.416 36.49408 94.25536 10.65856 62.4064-3.3728 119.11936-41.35808 169.50016-37.87136 50.22848-89.12384 79.04768-151.0592 86.68288-69.376 8.55424-130.6048-11.64928-182.97344-59.0336m234.77248-308.38784c-4.71168-6.65984-10.2016-12.57728-16.7936-17.41824-27.78368-20.40832-58.83648-24.52736-91.15392-15.51872-30.048 8.37376-52.27264 26.62144-60.46464 58.32832-3.8144 14.76096 11.6224 29.66528 26.5024 26.29632 10.26304-2.32448 15.936-9.09952 19.61472-18.3296 5.1968-13.0496 14.19776-22.25408 27.95136-25.984 7.39456-2.00576 14.9824-1.72672 22.71232-1.472 20.41088 0.672 41.17248 19.92576 34.42432 48.6016-2.8928 12.2944-11.34976 20.73344-19.96032 29.07392-9.1776 8.8896-19.29088 16.81408-27.35744 26.84928-10.16704 12.65024-16.73984 26.74816-16.91904 43.2064-0.1408 13.03552 7.54816 21.3248 20.28928 22.65344 12.3136 1.28256 20.4096-4.6528 22.51136-18.00192 2.26432-14.37952 9.792-25.08672 20.4608-34.2912 8.55168-7.37664 16.9856-14.91968 25.09824-22.77376 29.64992-28.70272 34.8224-67.61216 13.08416-101.21984M546.4448 689.152c3.58912-15.9744-8.8192-34.05568-25.41568-37.0368-18.91072-3.39584-37.376 9.43616-39.45856 27.424-1.87008 16.13824 10.0352 32.6208 25.66784 35.53536 17.69728 3.29984 34.2528-7.27168 39.2064-25.92256z\" fill=\"#d81e06\"><\/path><\/svg> <\/div>\n<\/p><\/div>\n<p class=\"wp-block-paragraph\"><strong>Q: Quelle est la constante di\u00e9lectrique de l'eau?<\/strong><\/p>\n<\/div>\n<div class=\"wp-block-group is-nowrap is-layout-flex wp-container-core-group-is-layout-b7d9c19b wp-block-group-is-layout-flex\" style=\"margin-top:0;margin-bottom:0;padding-top:0;padding-right:0;padding-bottom:0;padding-left:0\">\n<div class=\"wp-block-safe-svg-svg-icon safe-svg-cover\" style=\"text-align: left;\">\n<div class=\"safe-svg-inside safe-svg-inline\" style=\"width: 32px; height: 32px; background-color: var(--wp--preset--color--); color: var(--wp--preset--color--); padding-top: 0; padding-right: 0; padding-bottom: 0; padding-left: 0; margin-top: 0; margin-right: 0; margin-bottom: 0; margin-left: 0;\"><?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?> <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" class=\"icon\" viewbox=\"0 0 1024 1024\" version=\"1.1\" width=\"32\" height=\"32\"><path d=\"M501.0496 225.9008c1.9776-4.30848 3.3792-8.41984 5.65248-11.9744 3.82464-5.98656 11.03232-5.89184 13.73056 0.51968 27.92704 66.35136 74.78016 119.73888 119.27424 174.7456 25.23776 31.20128 49.71008 62.8992 68.15104 98.80448 17.57952 34.2272 28.4416 70.3424 29.28128 108.89088 0.8832 40.52608-9.22368 78.46144-30.06976 113.39008-32.99328 55.27936-80.94464 90.8096-143.59424 104.55296-76.60288 16.80256-145.1776-1.41696-203.41376-54.08384-39.3472-35.584-62.4128-80.41984-68.70272-133.44512-6.31808-53.26336 6.912-102.2336 32.6464-148.46336 21.2736-38.2208 48.8768-71.87584 76.31104-105.62432 32.3008-39.73248 64.4672-79.53536 89.2032-124.6592 3.9936-7.28576 7.57376-14.79808 11.53024-22.65344m-36.41216 378.90304c-15.41376-15.35232-30.78784-30.7456-46.26176-46.03648-6.16832-6.09536-10.1184-6.1056-16.38016-0.01024a1031.35872 1031.35872 0 0 0-22.57792 22.6496c-6.88768 7.13344-6.80448 9.34144 0.13696 16.43136 16.2624 16.6144 32.58112 33.17248 48.8448 49.78432 13.8752 14.17216 27.62752 28.46336 41.58464 42.55104 6.6816 6.7456 11.33696 6.4768 17.856-0.44032 1.16992-1.2416 2.26432-2.55232 3.38816-3.83616 40.47488-46.19008 80.93952-92.3904 121.43104-138.5664 12.512-14.26944 25.09056-28.48 37.664-42.69568 3.30496-3.7376 5.07136-7.7952 1.09696-11.89504-8.45696-8.72704-17.0624-17.3184-25.85088-25.71008-3.54688-3.38688-7.74016-3.2768-11.52256 0.06784-2.0736 1.83296-4.1024 3.73504-5.9776 5.7664-16.48256 17.85728-32.98944 35.69536-49.36704 53.64864-23.70688 25.98528-47.32544 52.0512-70.9568 78.1056-13.6 14.99648-9.64224 12.96512-23.10784 0.1856z\" fill=\"#21a529\"><\/path><\/svg> <\/div>\n<\/p><\/div>\n<p class=\"wp-block-paragraph\"><strong>A :<\/strong> L'eau a une grande capacit\u00e9 relative d'environ 80 \u00e0 temp\u00e9rature ambiante, ce qui donne un \u00e9cho radar tr\u00e8s fort et en fait le moyen le plus facile \u00e0 mesurer.<\/p>\n<\/div>\n<\/div>\n<h2 class=\"wp-block-heading\"><strong>R\u00e9f\u00e9rences<\/strong><\/h2>\n<ul class=\"wp-block-list\">\n<li>Vega, <em><a href=\"https:\/\/www.vega.com\/en\/products\/product-catalog\/level\/radar\" target=\"_blank\" rel=\"noreferrer noopener\">Mesure du niveau radar<\/a><\/em> \u2014 notes techniques sur radar sans contact et \u00e0 ondes guid\u00e9es.<\/li>\n<li>Endress+Hauser, <em><a href=\"https:\/\/www.endress.com\/en\/Field-instruments-overview\/Level-measurement\/Radar\" target=\"_blank\" rel=\"noreferrer noopener\">Mesure du niveau radar<\/a><\/em> \u2014 besoins en constante di\u00e9lectrique et mesure de l'interface.<\/li>\n<li>Emerson, <em><a href=\"https:\/\/www.emerson.com\/en-us\/automation\/measurement-instrumentation\/level\" target=\"_blank\" rel=\"noreferrer noopener\">Instruments de mesure de niveau<\/a><\/em> \u2014 orientation des applications.<\/li>\n<li>CRC Handbook of Chemistry and Physics \u2014 source des valeurs relatives de permistibilit\u00e9 pr\u00e9sent\u00e9es ci-dessus.<\/li>\n<li>Kacise, <em><a href=\"https:\/\/www.kcsensor.com\/fr\/product\/kld804-radar-level-sensor\/\" target=\"_blank\" rel=\"noreferrer noopener\">KLD804 Capteur de niveau radar 80 GHz<\/a><\/em> fiche technique.<\/li>\n<\/ul>\n<p class=\"wp-block-paragraph\">","protected":false},"excerpt":{"rendered":"<p>The dielectric constant (relative permittivity, \u03b5r) of the medium determines how much of the radar signal is reflected to the antenna. Media with \u03b5r > 3.6 reflect strongly and are easy targets; low-\u03b5r hydrocarbons (typically 1.4\u20134.0) reflect only a small fraction of the signal and require guided-wave radar or high-frequency (80\u00a0GHz) non-contact radar for reliable [&hellip;]<\/p>\n","protected":false},"author":6,"featured_media":17192,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[319],"tags":[238],"class_list":["post-14228","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-radar-level-meter","tag-radar"],"acf":[],"_links":{"self":[{"href":"https:\/\/www.kcsensor.com\/fr\/wp-json\/wp\/v2\/posts\/14228","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.kcsensor.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.kcsensor.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.kcsensor.com\/fr\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/www.kcsensor.com\/fr\/wp-json\/wp\/v2\/comments?post=14228"}],"version-history":[{"count":0,"href":"https:\/\/www.kcsensor.com\/fr\/wp-json\/wp\/v2\/posts\/14228\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.kcsensor.com\/fr\/wp-json\/wp\/v2\/media\/17192"}],"wp:attachment":[{"href":"https:\/\/www.kcsensor.com\/fr\/wp-json\/wp\/v2\/media?parent=14228"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.kcsensor.com\/fr\/wp-json\/wp\/v2\/categories?post=14228"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.kcsensor.com\/fr\/wp-json\/wp\/v2\/tags?post=14228"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}