{"id":2654,"date":"2026-07-17T04:00:00","date_gmt":"2026-07-17T04:00:00","guid":{"rendered":"https:\/\/chac-electric.com\/blog\/thermal-overload-relay-motor-protection-selection\/"},"modified":"2026-08-03T03:30:04","modified_gmt":"2026-08-03T03:30:04","slug":"seleccion-de-rele-de-sobrecarga-termica-para-proteccion-de-motor","status":"publish","type":"post","link":"https:\/\/chac-electric.com\/es\/blog\/thermal-overload-relay-motor-protection-selection\/","title":{"rendered":"\u00bfC\u00f3mo deben los constructores de paneles dimensionar un rel\u00e9 de sobrecarga t\u00e9rmica para motores trif\u00e1sicos?"},"content":{"rendered":"<p>Los montadores de paneles dimensionan un rel\u00e9 de sobrecarga t\u00e9rmica a partir de la corriente a plena carga del motor, el factor de servicio, el n\u00famero de fases, la temperatura ambiente y el ciclo de trabajo del contactor; luego, seleccionan un elemento calefactor o banda de disparo electr\u00f3nica y confirman la coordinaci\u00f3n con el contactor y el dispositivo de protecci\u00f3n contra cortocircuitos aguas arriba.<\/p>\n<p>Esta gu\u00eda se enfoca en los circuitos derivados de motores trif\u00e1sicos en arrancadores de bajo voltaje. Para las opciones de contactor frente a rel\u00e9 de control en el mismo conjunto, consulte la <a href=\"https:\/\/chac-electric.com\/es\/blog\/ac-contactor-vs-relay-motor-control-guide\/\">Gu\u00eda de contactores de CA vs rel\u00e9s<\/a>. Para plataformas moldeadas a nivel de alimentador, consulte la <a href=\"https:\/\/chac-electric.com\/es\/blog\/mccb-buying-guide-oem-distributor-buyers\/\">Gu\u00eda de compra de MCCB para compradores OEM<\/a>.<\/p>\n<figure><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-2759 size-large\" src=\"https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/55882b340da34aefa66baf12fe394289-1024x683.webp\" alt=\"CQR2 Thermal Overload Relay\" width=\"1024\" height=\"683\" srcset=\"https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/55882b340da34aefa66baf12fe394289-1024x683.webp 1024w, https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/55882b340da34aefa66baf12fe394289-300x200.webp 300w, https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/55882b340da34aefa66baf12fe394289-768x512.webp 768w, https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/55882b340da34aefa66baf12fe394289-600x400.webp 600w, https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/55882b340da34aefa66baf12fe394289.webp 1536w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n<nav class=\"b2b-toc\">\n<h2>\u00cdndice<\/h2>\n<ul>\n<li><a href=\"#part-1-what-does-a-thermal-overload-relay-protect-in-a-motor-starter\">Parte 1. \u00bfQu\u00e9 protege un rel\u00e9 de sobrecarga t\u00e9rmica en un arrancador de motor?<\/a><\/li>\n<li><a href=\"#part-2-which-motor-data-points-drive-overload-relay-selection\">Parte 2. \u00bfQu\u00e9 datos del motor impulsan la selecci\u00f3n del rel\u00e9 de sobrecarga?<\/a><\/li>\n<li><a href=\"#part-3-when-is-bimetallic-overload-enough-versus-electronic-thermal-protection\">Parte 3. \u00bfCu\u00e1ndo es suficiente la protecci\u00f3n contra sobrecarga bimet\u00e1lica frente a la protecci\u00f3n t\u00e9rmica electr\u00f3nica?<\/a><\/li>\n<li><a href=\"#part-4-how-should-overload-relays-pair-with-contactors-in-three-phase-starters\">Parte 4. \u00bfC\u00f3mo deben emparejarse los rel\u00e9s de sobrecarga con los contactores en los arrancadores trif\u00e1sicos?<\/a><\/li>\n<li><a href=\"#part-5-how-do-thermal-overload-relays-differ-from-mpcbs-in-the-same-panel\">Parte 5. \u00bfEn qu\u00e9 se diferencian los rel\u00e9s de sobrecarga t\u00e9rmica de los MPCB en el mismo panel?<\/a><\/li>\n<li><a href=\"#part-6-which-chac-routes-support-motor-overload-and-starter-programs\">Parte 6. \u00bfQu\u00e9 rutas CHAC admiten la sobrecarga del motor y los programas de arranque?<\/a><\/li>\n<li><a href=\"#part-7-what-are-the-fit-boundaries-for-overload-relay-selection\">Parte 7. \u00bfCu\u00e1les son los l\u00edmites de ajuste para la selecci\u00f3n de un rel\u00e9 de sobrecarga?<\/a><\/li>\n<\/ul>\n<\/nav>\n<h2 id=\"part-1-what-does-a-thermal-overload-relay-protect-in-a-motor-starter\">Parte 1. \u00bfQu\u00e9 protege un rel\u00e9 de sobrecarga t\u00e9rmica en un arrancador de motor?<\/h2>\n<p>A <strong>rel\u00e9 de sobrecarga t\u00e9rmica<\/strong> responde a sobrecorrientes sostenidas que pueden sobrecalentar el devanado del motor \u2014 condiciones que el dispositivo de cortocircuito aguas arriba no est\u00e1 dise\u00f1ado para tolerar durante largos per\u00edodos. En un arrancador directo en l\u00ednea, el contactor conmuta la alimentaci\u00f3n mientras que el rel\u00e9 de sobrecarga abre el circuito de control (o dispara el arrancador) cuando la acumulaci\u00f3n de calor excede la caracter\u00edstica de disparo seleccionada.<\/p>\n<table>\n<thead>\n<tr>\n<th>Dispositivo en el arranque<\/th>\n<th>Funci\u00f3n principal<\/th>\n<th>Fallo t\u00edpico si el dispositivo es incorrecto<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Interruptor de cortocircuito \/ fusibles<\/td>\n<td>Interrupci\u00f3n a nivel de fallo<\/td>\n<td>N\/A para minutos sostenidos de sobrecarga<\/td>\n<\/tr>\n<tr>\n<td>Contacto<\/td>\n<td>Conmutaci\u00f3n frecuente de energ\u00eda<\/td>\n<td>Contactos soldados si son de un tama\u00f1o inferior al adecuado<\/td>\n<\/tr>\n<tr>\n<td>Rel\u00e9 de sobrecarga t\u00e9rmica<\/td>\n<td>Patrones de sobrecorriente sostenida \/ p\u00e9rdida de fase<\/td>\n<td>El motor se quema si la temperatura del calentador es demasiado alta<\/td>\n<\/tr>\n<tr>\n<td>Rel\u00e9 de control (opcional)<\/td>\n<td>L\u00f3gica y enclavamientos<\/td>\n<td>Arranque defectuoso, no da\u00f1os por calor<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Las envolventes IEC 60947-4-1 definen los arrancadores de motor como combinaciones coordinadas de contactores y dispositivos de sobrecarga u otros dispositivos de protecci\u00f3n. Trate la sobrecarga como parte de un <strong>kit de inicio<\/strong>, no es un art\u00edculo de cat\u00e1logo independiente.<\/p>\n<h2 id=\"part-2-which-motor-data-points-drive-overload-relay-selection\">Parte 2. \u00bfQu\u00e9 datos del motor impulsan la selecci\u00f3n del rel\u00e9 de sobrecarga?<\/h2>\n<p>Las tablas del calentador y las curvas de disparo electr\u00f3nico comienzan con los datos de la placa de caracter\u00edsticas. Las hojas de motor incompletas son la causa principal de disparos err\u00f3neos o protecci\u00f3n inadecuada.<\/p>\n<table>\n<thead>\n<tr>\n<th>Dato<\/th>\n<th>De d\u00f3nde viene<\/th>\n<th>Impacto de la selecci\u00f3n<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Corriente a plena carga (FLA)<\/td>\n<td>Placa de motor<\/td>\n<td>Base para calentador \/ banda de viaje<\/td>\n<\/tr>\n<tr>\n<td>Factor de servicio<\/td>\n<td>Placa de caracter\u00edsticas<\/td>\n<td>Puede ajustar la corriente continua admisible<\/td>\n<\/tr>\n<tr>\n<td>Tensi\u00f3n y fase (3P)<\/td>\n<td>Placa de identificaci\u00f3n y suministro<\/td>\n<td>Confirma la asignaci\u00f3n de sobrecarga tripolar<\/td>\n<\/tr>\n<tr>\n<td>Deber \/ m\u00e9todo de arranque<\/td>\n<td>Aplicaci\u00f3n (DOL, ingenier\u00eda inversa, etc.)<\/td>\n<td>Clase de viaje y coordinaci\u00f3n<\/td>\n<\/tr>\n<tr>\n<td>Temperatura ambiente<\/td>\n<td>Entorno de instalaci\u00f3n<\/td>\n<td>Reducci\u00f3n de potencia seg\u00fan datos del fabricante<\/td>\n<\/tr>\n<tr>\n<td>Altitud (si aplica)<\/td>\n<td>Datos del sitio<\/td>\n<td>Puede reducir la capacidad t\u00e9rmica<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3>Lista de verificaci\u00f3n trif\u00e1sica antes de realizar el pedido<\/h3>\n<ol>\n<li>Confirmar <strong>cada fase<\/strong> lleva los elementos de detecci\u00f3n de sobrecarga requeridos por el dise\u00f1o del arrancador.<\/li>\n<li>Grabar <strong>FLA a voltaje nominal<\/strong>, no solo la potencia.<\/li>\n<li>Nota <strong>frecuencia inicial<\/strong> \u2014 los arranques frecuentes pueden requerir un disparo electr\u00f3nico con ajuste m\u00e1s amplio.<\/li>\n<li>Captura <strong>restablecer tipo<\/strong> requerido (manual vs autom\u00e1tico) para la pol\u00edtica de mantenimiento.<\/li>\n<li>Lista <strong>bastidor del contactor<\/strong> ya elegido, as\u00ed que la sobrecarga aumenta y el autob\u00fas coincide.<\/li>\n<\/ol>\n<h2 id=\"part-3-when-is-bimetallic-overload-enough-versus-electronic-thermal-protection\">Parte 3. \u00bfCu\u00e1ndo es suficiente la protecci\u00f3n contra sobrecarga bimet\u00e1lica frente a la protecci\u00f3n t\u00e9rmica electr\u00f3nica?<\/h2>\n<p><strong>Rel\u00e9s de sobrecarga t\u00e9rmica bimet\u00e1licos<\/strong> usar tiras bimet\u00e1licas calentadas para abrir contactos despu\u00e9s de una sobrecarga sostenida. <strong>Sobrecarga t\u00e9rmica electr\u00f3nica<\/strong> los dispositivos utilizan sensores y par\u00e1metros de disparo ajustables, a menudo con una mayor correspondencia con ciclos de trabajo complejos.<\/p>\n<table>\n<thead>\n<tr>\n<th>Tecnolog\u00eda<\/th>\n<th>Mejor ajuste cuando<\/th>\n<th>Limitaci\u00f3n<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>T\u00e9rmico bimet\u00e1lico<\/td>\n<td>Bombas, ventiladores y compresores DOL est\u00e1ndar con funcionamiento estable<\/td>\n<td>Bandas de calentamiento fijas; sensibilidad ambiental<\/td>\n<\/tr>\n<tr>\n<td>T\u00e9rmico electr\u00f3nico \/ EOL<\/td>\n<td>Carga variable, ajuste preciso, necesidades de diagn\u00f3stico<\/td>\n<td>Mayor costo; configuraci\u00f3n de par\u00e1metros requerida<\/td>\n<\/tr>\n<tr>\n<td>Interruptor de protecci\u00f3n de motor (IPM)<\/td>\n<td>Rama integrada con funci\u00f3n de cortocircuito y sobrecarga<\/td>\n<td>Diferente v\u00eda de coordinaci\u00f3n (ver Parte 5)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Si la aplicaci\u00f3n incluye enchufado reversible, funcionamiento intermitente o funcionamiento intensivo intermitente, revise la clase de disparo y la gu\u00eda del fabricante; no asuma que el escal\u00f3n m\u00e1s bajo del calentador a\u00fan protege el motor.<\/p>\n<h2 id=\"part-4-how-should-overload-relays-pair-with-contactors-in-three-phase-starters\">Parte 4. \u00bfC\u00f3mo deben emparejarse los rel\u00e9s de sobrecarga con los contactores en los arrancadores trif\u00e1sicos?<\/h2>\n<p>El rel\u00e9 de sobrecarga se monta sobre o adyacente al <strong>Contactor de CA<\/strong> y comparte el circuito de potencia del motor. El cableado de control generalmente dirige los contactos auxiliares de sobrecarga para desconectar la bobina del contactor en caso de disparo.<\/p>\n<blockquote>\n<h5><strong>CHAC RCCB Recomendado:<\/strong><\/h5>\n<h5><a href=\"https:\/\/chac-electric.com\/es\/product\/cqc6-series-industrial-ac-contactor-oem-manufacturer\/\">Fabricante OEM de contactores de CA industriales serie CQC6 | CHAC Electric<\/a><\/h5>\n<figure><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-2688 alignnone\" src=\"https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/01-cqc6-600x600-1.webp\" alt=\"Fabricante de OEM de contactor de CA industrial serie CQC6\" width=\"600\" height=\"600\" srcset=\"https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/01-cqc6-600x600-1.webp 600w, https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/01-cqc6-600x600-1-300x300.webp 300w, https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/01-cqc6-600x600-1-150x150.webp 150w, https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/01-cqc6-600x600-1-100x100.webp 100w\" sizes=\"auto, (max-width: 600px) 100vw, 600px\" \/><\/figure>\n<\/blockquote>\n<table>\n<thead>\n<tr>\n<th>Paso de coordinaci\u00f3n<\/th>\n<th>Acci\u00f3n<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Emparejar familia de marcos<\/td>\n<td>Sobrecarga de base apta para contactor de l\u00ednea<\/td>\n<\/tr>\n<tr>\n<td>Verificar n\u00famero de polos<\/td>\n<td>Sobrecarga de tres polos para motor trif\u00e1sico est\u00e1ndar<\/td>\n<\/tr>\n<tr>\n<td>Asignar auxiliares de viaje<\/td>\n<td>NA\/NC para PLC e indicador<\/td>\n<\/tr>\n<tr>\n<td>Verificar dispositivo de cortocircuito aguas arriba<\/td>\n<td>Los interruptores autom\u00e1ticos o fusibles eliminan las fallas antes de que la sobrecarga caliente<\/td>\n<\/tr>\n<tr>\n<td>Restablecer acceso al documento<\/td>\n<td>Manual reset location reachable for maintenance<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Starter layouts for three-phase motors are documented in wiring diagrams such as the CQR2 thermal overload reference on CHAC media. Use the diagram as a layout pattern \u2014 final approval still requires project-specific motor data.<\/p>\n<p>For contactor sizing and control-relay logic around the same assembly, cross-read the <a href=\"https:\/\/chac-electric.com\/es\/blog\/ac-contactor-vs-relay-motor-control-guide\/\">Gu\u00eda de contactores de CA vs rel\u00e9s<\/a>.<\/p>\n<h2 id=\"part-5-how-do-thermal-overload-relays-differ-from-mpcbs-in-the-same-panel\">Parte 5. \u00bfEn qu\u00e9 se diferencian los rel\u00e9s de sobrecarga t\u00e9rmica de los MPCB en el mismo panel?<\/h2>\n<p>Both address motor branch protection, but the device class and coordination differ.<\/p>\n<table>\n<thead>\n<tr>\n<th>Aspect<\/th>\n<th>Thermal overload relay in starter<\/th>\n<th>Interruptor de protecci\u00f3n de motor (IPM)<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Montaje<\/td>\n<td>On contactor starter rail<\/td>\n<td>Often standalone branch device<\/td>\n<\/tr>\n<tr>\n<td>Short-circuit duty<\/td>\n<td>Relies on upstream breaker\/fuse<\/td>\n<td>Integrates short-circuit trip function<\/td>\n<\/tr>\n<tr>\n<td>Adjustment<\/td>\n<td>Heater or electronic trip on overload<\/td>\n<td>Combined motor-protector curves<\/td>\n<\/tr>\n<tr>\n<td>Typical use<\/td>\n<td>Classic DOL \/ reversing starters<\/td>\n<td>Compact motor feeder modules<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Do not specify both devices on the same motor branch without an engineered coordination study. Choose starter-based overload or MPCB feeder based on panel standard and local practice.<\/p>\n<h2 id=\"part-6-which-chac-routes-support-motor-overload-and-starter-programs\">Parte 6. \u00bfQu\u00e9 rutas CHAC admiten la sobrecarga del motor y los programas de arranque?<\/h2>\n<h3>Recomendaci\u00f3n de producto<\/h3>\n<p>CHAC industrial control products include contactor platforms, thermal overload devices, and motor protection circuit breakers for OEM panel programs.<\/p>\n<table>\n<thead>\n<tr>\n<th>Solicitud<\/th>\n<th>CHAC starting point<\/th>\n<th>RFQ focus<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Standard 3P DOL starter line<\/td>\n<td><a href=\"https:\/\/chac-electric.com\/es\/ac-contactor\/\">AC contactor category<\/a> + <a href=\"https:\/\/chac-electric.com\/es\/thermal-relay\/\">thermal relay category<\/a><\/td>\n<td>FLA, heater range, contactor frame<\/td>\n<\/tr>\n<tr>\n<td>Integrated motor branch protection<\/td>\n<td><a href=\"https:\/\/chac-electric.com\/es\/product\/cqv2-series-motor-protection-circuit-breaker\/\">CQV2 Motor Protection Circuit Breaker<\/a><\/td>\n<td>MPCB curve, feeder fault level<\/td>\n<\/tr>\n<tr>\n<td>Industrial contactor OEM platform<\/td>\n<td><a href=\"https:\/\/chac-electric.com\/es\/product\/cqc6-series-industrial-ac-contactor-oem-manufacturer\/\">Fabricante de OEM de contactor de CA industrial serie CQC6<\/a><\/td>\n<td>Poles, coil, auxiliaries, overload pairing<\/td>\n<\/tr>\n<tr>\n<td>Private-label starter kits<\/td>\n<td><a href=\"https:\/\/chac-electric.com\/es\/personalizacion-de-control-industrial\/\">Industrial control customization<\/a><\/td>\n<td>Branding, packaging, regional marks<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>Submit motor nameplate data and starter single-line layout through <a href=\"https:\/\/chac-electric.com\/es\/contactanos\/\">Contact CHAC Electric<\/a> for platform scoping.<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"alignnone size-large wp-image-2810 aligncenter\" src=\"https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/80f72baa-f120-46fa-baee-a26baf190c9f-1024x819.webp\" alt=\"Los mejores contactores de CA revolucionan las operaciones el\u00e9ctricas\" width=\"1024\" height=\"819\" srcset=\"https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/80f72baa-f120-46fa-baee-a26baf190c9f-1024x819.webp 1024w, https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/80f72baa-f120-46fa-baee-a26baf190c9f-300x240.webp 300w, https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/80f72baa-f120-46fa-baee-a26baf190c9f-768x615.webp 768w, https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/80f72baa-f120-46fa-baee-a26baf190c9f-600x480.webp 600w, https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/07\/80f72baa-f120-46fa-baee-a26baf190c9f.webp 1402w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/p>\n<h2 id=\"part-7-what-are-the-fit-boundaries-for-overload-relay-selection\">Parte 7. \u00bfCu\u00e1les son los l\u00edmites de ajuste para la selecci\u00f3n de un rel\u00e9 de sobrecarga?<\/h2>\n<p>This guide supports low-voltage <strong>thermal overload relay selection<\/strong> for motor starters. It does not replace:<\/p>\n<ul>\n<li>Motor cable sizing or voltage-drop calculations<\/li>\n<li>Short-circuit coordination studies<\/li>\n<li>VFD output protection or harmonic heating analysis<\/li>\n<li>Medium-voltage motor protection<\/li>\n<li>Explosion-proof or marine classification rules<\/li>\n<\/ul>\n<p>When motor data is incomplete or duty is non-standard, hold heater approval until nameplate FLA and ambient conditions are confirmed.<\/p>\n<h2>Preguntas frecuentes<\/h2>\n<h3>What is a thermal overload relay?<\/h3>\n<p>A thermal overload relay is a protective device in a motor starter that detects sustained overcurrent \u2014 usually through bimetallic heating or electronic sensing \u2014 and opens the control circuit or trips the starter to reduce motor overheating risk. It is coordinated with a contactor under motor-starter standards such as IEC 60947-4-1.<\/p>\n<h3>How do you size a thermal overload relay for a three-phase motor?<\/h3>\n<p>Start from motor full-load current on the nameplate, adjust for service factor and manufacturer ambient derating rules, select the heater or electronic trip band that covers that current, and verify the three-pole device matches the contactor frame and starter wiring layout.<\/p>\n<h3>What is the difference between a thermal overload relay and an MPCB?<\/h3>\n<p>A thermal overload relay protects against sustained overload in a contactor-based starter and relies on upstream devices for short-circuit interruption. An MPCB combines motor overload and short-circuit protection in one branch device. They serve different starter architectures and should not be duplicated on the same branch without engineering review.<\/p>\n<h3>What motor nameplate data is required for overload selection?<\/h3>\n<p>At minimum: rated voltage, full-load current, phase, service factor if listed, and intended duty. Starting method, ambient temperature, and altitude also affect trip selection when published derating applies.<\/p>\n<h3>Can one overload relay protect multiple motors?<\/h3>\n<p>Standard practice is one overload relay (or MPCB) per motor branch. Sharing one overload across multiple motors requires engineered interlocks and is uncommon in general industrial panels.<\/p>\n<h3>How does a thermal overload relay coordinate with a contactor?<\/h3>\n<p>The overload sits in the motor power circuit with the contactor and uses auxiliary contacts to de-energize the contactor coil when trip conditions occur. The contactor handles switching duty; the overload handles sustained overcurrent detection.<\/p>\n<h3>When should buyers choose electronic instead of bimetallic overload?<\/h3>\n<p>Choose electronic thermal protection when adjustable trip parameters, tighter duty matching, or diagnostic features justify the cost \u2014 especially with variable duty cycles, frequent starts, or wide ambient swings beyond standard bimetallic bands.<\/p>\n<h2>Referencias<\/h2>\n<ul>\n<li><a href=\"https:\/\/webstore.iec.ch\/en\/publication\/6199\" rel=\"nofollow noopener\" target=\"_blank\">IEC 60947-4-1 Contactors and motor-starters \u2014 Electromechanical contactors and motor-starters<\/a><\/li>\n<\/ul>\n<h2>Related Articles<\/h2>\n<ul>\n<li><a href=\"https:\/\/chac-electric.com\/es\/blog\/ac-contactor-vs-relay-motor-control-guide\/\">AC Contactor vs Relay: Motor Control Selection Guide<\/a><\/li>\n<li><a href=\"https:\/\/chac-electric.com\/es\/blog\/mccb-buying-guide-oem-distributor-buyers\/\">Molded Case Circuit Breaker Buying Guide for OEM Buyers<\/a><\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"<p>Panel builders size a thermal overload relay from motor full-load current, service factor, phase count, ambient temperature, and starter duty \u2014 then match a heater or electronic trip band and confirm coordination with the contactor and upstream short-circuit device. This guide focuses on three-phase motor branches in low-voltage starters. For contactor versus control-relay choices in [&hellip;]<\/p>\n","protected":false},"author":10,"featured_media":2808,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-2654","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog"],"blocksy_meta":{"styles_descriptor":{"styles":{"desktop":"","tablet":"","mobile":""},"google_fonts":[],"version":7}},"acf":[],"_links":{"self":[{"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/posts\/2654","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/users\/10"}],"replies":[{"embeddable":true,"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/comments?post=2654"}],"version-history":[{"count":8,"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/posts\/2654\/revisions"}],"predecessor-version":[{"id":3328,"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/posts\/2654\/revisions\/3328"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/media\/2808"}],"wp:attachment":[{"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/media?parent=2654"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/categories?post=2654"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/tags?post=2654"}],"curies":[{"name":"bien jugado","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}