{"id":8983,"date":"2026-10-30T11:30:00","date_gmt":"2026-10-30T11:30:00","guid":{"rendered":"https:\/\/www.simplybuyglobal.com\/?p=8983"},"modified":"2026-11-05T08:59:53","modified_gmt":"2026-11-05T08:59:53","slug":"how-to-choose-a-reversing-contactor-for-a-three-phase-motor","status":"publish","type":"post","link":"https:\/\/www.simplybuyglobal.com\/de\/blog\/motor-control\/ac-contactor\/how-to-choose-a-reversing-contactor-for-a-three-phase-motor\/","title":{"rendered":"How to Choose a Reversing Contactor for a Three-Phase Motor"},"content":{"rendered":"<style id=\"wp-draft-card-style\">      .hero-card {       display: flex;       flex-wrap: wrap;       align-items: center;       background: #f7f8fa;       border-radius: 16px;       box-shadow: 0 6px 20px rgba(0, 0, 0, 0.05);       padding: 24px;       max-width: 700px;       margin: 35px auto;       font-family: Arial, sans-serif;       text-decoration: none;       color: inherit;  font-family: 'Poppins';     }      .hero-image {       width: 220px;       height: auto;       border-radius: 12px;       object-fit: cover;       flex-shrink: 0;     }      .hero-content {       padding-left: 24px;       flex: 1;       min-width: 260px;     }      .hero-title {       font-size: 1.6rem;       font-weight: bold;       margin-bottom: 12px;       color: #222;       font-family: 'Poppins', Arial, sans-serif;     }      .hero-description {       font-size: 1rem;       color: #555;       margin-bottom: 18px;     }      .hero-link {       display: inline-block;       padding: 10px 20px;       background-color: #0066cc;       color: #fff;       text-decoration: none;       border-radius: 8px;       font-weight: bold;       transition: background 0.2s ease-in-out;     }      .hero-link:hover {       background-color: #004c99;     }      @media (max-width: 640px) {       .hero-card {         flex-direction: column;         text-align: center;       }        .hero-content {         padding-left: 0;         padding-top: 20px;       }        .hero-image {         width: 100%;         max-width: 280px;       }     }    <\/style>\n\n\n<p><strong>Schnelle Antwort:<\/strong> Choose a reversing contactor by matching its AC-3 rating to the motor&#8217;s full-load current at the actual supply voltage. Then confirm coil voltage, three-pole configuration, auxiliary contacts, and mechanical plus electrical interlock. For frequent plugging or inching, check the duty rating and the manufacturer&#8217;s guidance. Also confirm overload and short-circuit protection, panel fit, and the exact model suffix. SIMPLYBUY helps buyers compare reversing contactors across brands and review the complete part number, accessories, and BOM before quoting.<\/p>\n<p>A reversing contactor decides whether a three-phase motor can change direction safely and repeatedly. This reversing contactor selection guide gives you a practical sequence and the details to send for an accurate quote.<\/p>\n<h2>What Is a Reversing Contactor, and When Do You Need One?<\/h2>\n<p>A reversing contactor is an assembly of two contactors that connects a three-phase motor for forward or reverse rotation. It changes the phase sequence, so the magnetic field rotates the other way.<\/p>\n<p>Some buyers call the same assembly a forward reverse contactor; the selection checks are the same.<\/p>\n<p>You need one when the machine must run both ways. Common examples include conveyors that back up, hoists, sliding doors, and mixers that reverse for cleaning. If the motor only runs one way, a standard <a href=\"https:\/\/www.simplybuyglobal.com\/de\/product-category\/motor-control\/ac-contactor\/\" rel=\"noopener noreferrer\" target=\"_blank\">Wechselstromsch\u00fctz<\/a> is usually enough.<\/p>\n<h3>How Does a Reversing Contactor Reverse a Three-Phase Motor?<\/h3>\n<p>A three-phase motor changes direction when two supply phases are swapped. The forward contactor connects L1, L2, and L3 in one order; the reverse contactor swaps two of those phases. The two contactors must never close at the same time. A mechanical interlock prevents both from engaging, while normally closed auxiliary contacts provide an electrical interlock. The control circuit should also delay the opposite command so the motor slows and the arc clears.<\/p>\n<h3>Reversing Contactor vs. Reversing Starter: Which Should You Buy?<\/h3>\n<p>A reversing contactor is a component. A reversing starter is a more complete assembly with the contactors, an overload relay, and sometimes a disconnect or enclosure. A <a href=\"https:\/\/www.simplybuyglobal.com\/de\/product-category\/motor-control\/motor-starter\/\" rel=\"noopener noreferrer\" target=\"_blank\">Motorstarter<\/a> is better when you want one factory-built part number.<\/p>\n<p>A reversing contactor is better when you build or repair a panel and already have the protection and control design. If you prefer an assembled unit, this <a href=\"https:\/\/www.simplybuyglobal.com\/de\/product\/siemens-sirius-3ra6250-1db32-compact-reversing-motor-starter-3-12a-24v-ac-dc-5-5kw-690v\/\" rel=\"noopener noreferrer\" target=\"_blank\">Siemens SIRIUS reversing motor starter<\/a> shows the type of package to compare. Check what is included rather than assuming every brand uses the same scope.<\/p>\n\n\n<div class=\"hero-card-wrapper\" data-wp-draft-card=\"1\"><a class=\"hero-card\" data-wp-card-role=\"button\" href=\"https:\/\/www.simplybuyglobal.com\/de\/product\/siemens-sirius-3ra6250-1db32-compact-reversing-motor-starter-3-12a-24v-ac-dc-5-5kw-690v\/\" rel=\"noopener noreferrer\" target=\"_blank\"><img decoding=\"async\" alt=\"\u897f\u95e8\u5b50 SIRIUS 3RA6250 \u7070\u8272\u7535\u673a\u63a7\u5236\u4e0e\u4fdd\u62a4\u88c5\u7f6e\uff0c\u6b63\u9762\u6709\u65cb\u94ae\u3001\u6309\u94ae\u548c\u63a5\u7ebf\u7aef\u5b50\uff0c\u5de6\u4fa7\u8d34\u6709\u6807\u7b7e\uff0c\u4e0b\u65b9\u5e26 SIEMENS \u6807\u5fd7\u3002\" class=\"hero-image\" data-wp-card-role=\"image\" src=\"https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/08\/2-61-scaled.jpg\"><div class=\"hero-content\"><div class=\"hero-title\" data-wp-card-role=\"title\">Siemens SIRIUS 3RA6250-1DB32 Kompakter Wendemotorstarter 3-12 A 24 V AC\/DC 5,5 kW 690 V<\/div><div class=\"hero-description\" data-wp-card-role=\"description\"><\/div><span class=\"hero-link\">view product<\/span><\/div><\/a><\/div>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"1600\" height=\"900\" src=\"https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-1-8.webp\" alt=\"\u897f\u95e8\u5b50\u6362\u5411\u8d77\u52a8\u5668\u4ea7\u54c1\u5bf9\u6bd4\u56fe\uff1a\u5de6\u4fa7\u4e3a\u5e26\u9632\u62a4\u529f\u80fd\u7684SIRIUS 3RA6250\u6362\u5411\u8d77\u52a8\u5668\uff0c\u4e2d\u95f4\u663e\u793a\u63a5\u89e6\u5668\u7ec4\u4ef6\u52a0\u673a\u68b0\u4e92\u9501\uff0c\u53f3\u4fa7\u4e3a\u96c6\u6210\u9632\u62a4\u7684\u8d77\u52a8\u5668\u5957\u88c5\uff0c\u4e0a\u65b9\u5217\u51fa\u8fc7\u8f7d\u3001\u77ed\u8def\u3001\u65ad\u76f8\u4fdd\u62a4\u53ca\u624b\u52a8\/\u81ea\u52a8\u590d\u4f4d\u529f\u80fd\u3002\" class=\"wp-image-8981\" srcset=\"https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-1-8.webp 1600w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-1-8-500x281.webp 500w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-1-8-1200x675.webp 1200w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-1-8-300x169.webp 300w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-1-8-768x432.webp 768w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-1-8-1536x864.webp 1536w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-1-8-18x10.webp 18w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-1-8-133x75.webp 133w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-1-8-960x540.webp 960w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-1-8-480x270.webp 480w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-1-8-800x450.webp 800w\" sizes=\"auto, (max-width:767px) 480px, (max-width:1600px) 100vw, 1600px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">What Should You Check Before Choosing a Reversing Contactor?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Start with the motor and how it will be used. The contactor must switch the actual load.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">What Motor Current and Duty Rating Do You Need?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Use the motor&#8217;s full-load current (FLC) at the actual supply voltage, not only the kW or HP figure. The same motor can draw different current at 400 V and 480 V, so the contactor&#8217;s AC-3 rating must cover normal starting and running. For frequent inching, plugging, or rapid direction changes, ask about AC-4 duty or a larger frame. An open-panel rating may need derating in a hot cabinet.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Which Coil Voltage Should You Specify?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The coil is a separate circuit from the motor supply. A contactor with a 400 V main circuit may have a 24 V DC, 110 V AC, 220 V AC, or 380 V AC coil. Match it to the control transformer or PLC output. Check the coil frequency: 50 Hz and 60 Hz coils are not always interchangeable. If a PLC drives the coil, confirm the output type and suppression requirements. Our <a href=\"https:\/\/www.simplybuyglobal.com\/de\/blog\/motor-control\/ac-contactor\/understanding-ac-contactor-coil\/\" rel=\"noopener noreferrer\" target=\"_blank\">contactor coil guide<\/a> explains these differences.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Are the Interlocks and Auxiliary Contacts Included?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Confirm whether the quoted reversing contactor includes a mechanical interlock, electrical interlock contacts, and the auxiliary contacts you need for holding, indication, or PLC feedback. Some assemblies include them; others list them as accessories. A mechanical interlock is not the only safety measure. The control circuit should also prevent a stuck contactor or wiring error from energizing both directions. Ask for the exact model&#8217;s wiring diagram.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">What Protection and Short-Circuit Coordination Do You Need?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">A reversing contactor does not replace motor overload or short-circuit protection. Add an <a href=\"https:\/\/www.simplybuyglobal.com\/de\/product-category\/motor-control\/overload-relay\/\" rel=\"noopener noreferrer\" target=\"_blank\">\u00dcberlastrelais<\/a> sized to the motor&#8217;s FLC and service factor, then check the manufacturer&#8217;s coordination table for the contactor, fuse, and breaker. An overload relay responds to sustained excess current; a fuse or breaker clears a short circuit. Our guide to <a href=\"https:\/\/www.simplybuyglobal.com\/de\/blog\/motor-control\/overload-relay\/overload-relay-vs-circuit-breaker\/\" rel=\"noopener noreferrer\" target=\"_blank\">overload protection vs. short-circuit protection<\/a> explains why one device cannot do both jobs.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Will the Contactor Fit Your Panel and Environment?<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Check the mounting style, dimensions, terminal size, wire range, and clearance around the arc chutes. A reversing assembly is wider, and the reverse contactor may need space for wiring loops. Confirm the mounting method and lug size.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Also check enclosure rating, ambient temperature, dust, and humidity. If the panel must meet UL, CSA, or IEC requirements, ask for documentation for the exact model. CE, UL, and IEC are not interchangeable claims. Our notes on <a href=\"https:\/\/www.simplybuyglobal.com\/de\/blog\/motor-control\/ul-nema-motor-control-products\/\" rel=\"noopener noreferrer\" target=\"_blank\">UL and NEMA motor-control products<\/a> can help you frame the question.<\/p>\n\n\n\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"1600\" height=\"900\" src=\"https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-2-8.webp\" alt=\"Siemens SIRIUS 3RA62 reversing starter with a rotary switch on the front, beside text reading Reversing Starter and four labeled icons for coil voltage, interlocks, overload and panel fit.\" class=\"wp-image-8982\" srcset=\"https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-2-8.webp 1600w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-2-8-500x281.webp 500w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-2-8-1200x675.webp 1200w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-2-8-300x169.webp 300w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-2-8-768x432.webp 768w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-2-8-1536x864.webp 1536w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-2-8-18x10.webp 18w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-2-8-133x75.webp 133w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-2-8-960x540.webp 960w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-2-8-480x270.webp 480w, https:\/\/www.simplybuyglobal.com\/wp-content\/uploads\/2026\/10\/inline-2-8-800x450.webp 800w\" sizes=\"auto, (max-width:767px) 480px, (max-width:1600px) 100vw, 1600px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Which Reversing Contactor Brands Should You Compare?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Common options include Schneider Electric TeSys, ABB AF and AX ranges, Siemens SIRIUS 3RT, Allen-Bradley 100-C, Mitsubishi, and Chint. These names narrow the search, but the full part number decides the coil, rating, auxiliary contacts, and accessories. A <a href=\"https:\/\/www.simplybuyglobal.com\/de\/blog\/motor-control\/ac-contactor\/top-contactor-brands-industrial\/\" rel=\"noopener noreferrer\" target=\"_blank\">contactor brand comparison<\/a> covers general differences; the exact datasheet is what matters for fit.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For buyers sourcing several brands, comparing like with like is harder. SIMPLYBUY is an electrical automation distributor and supply-chain integration platform, not a manufacturer. We can review a BOM, compare reversing contactor options across brands, and check the complete model, coil, and accessories before quoting. That helps when one panel mixes motor sizes or customer brands. <a href=\"https:\/\/www.simplybuyglobal.com\/de\/service\/\" rel=\"noopener noreferrer\" target=\"_blank\">Share your BOM<\/a> and we can discuss the options against your technical and delivery requirements.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">What Mistakes Cause Reversing Contactors to Fail?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The most serious mistake is allowing both contactors to energize, which can create a phase-to-phase short circuit. A missing interlock, welded contact, or logic error can cause this.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Other causes include choosing by kW alone, using the wrong coil voltage, reversing too quickly, and installing a unit in a hot or dusty panel without derating. Loose terminals and undersized wiring also cause overheating. If a contactor chatters, overheats, or fails to hold, stop using it and check the coil circuit and contacts. Our guide to <a href=\"https:\/\/www.simplybuyglobal.com\/de\/blog\/motor-control\/ac-contactor\/ac-contactor-failure-symptoms\/\" rel=\"noopener noreferrer\" target=\"_blank\">contactor failure symptoms<\/a> covers the first checks.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">What Information Do You Need for an Accurate Quote?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Send the motor nameplate details: kW or HP, FLC, voltage, phase, frequency, and service factor. Add the duty cycle, reversing frequency, coil voltage, and control supply. State whether you need an assembly, separate contactors, or a starter. Also include the overload range, auxiliary contacts, certification needs, quantity, and destination. A photo of the nameplate and terminals helps with replacements. With those details, a supplier can quote the correct configuration instead of a lookalike.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">What Is the Bottom Line?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Choose by load current and duty first, then coil voltage, interlock, protection, and physical fit. Compare the complete part number, not just brand or kW. For repetitive reversing, check the duty rating and control sequence.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">SIMPLYBUY can help you compare options across brands and review the motor, coil, and accessories before you order. Send your nameplate details, required configuration, quantity, and destination to <a href=\"https:\/\/www.simplybuyglobal.com\/de\/contact\/\" rel=\"noopener noreferrer\" target=\"_blank\">request a quote<\/a>. Accurate details upfront cost less than a wrong contactor.<\/p>\n\n\n\n<div data-wp-draft-contact=\"1\" style=\"text-align: center; width: 100%;\"><a data-wp-card-role=\"contact-button\" href=\"https:\/\/www.simplybuyglobal.com\/de\/contact\/\" rel=\"noopener noreferrer\" style=\"display: inline-flex;            align-items: center;            justify-content: center;            padding: 18px 27px;            min-height: 60px;            box-sizing: border-box;            background-color: #0C2B75;            color: #FFFFFF;            font-size: 16px;            font-weight: 500;            font-family: Arial, sans-serif;            text-decoration: none;            text-align: center;            border-radius: 50px;            line-height: 1.2;\" target=\"_blank\"> Discuss Your Reversing Contactor Order <\/a><\/div>","protected":false},"excerpt":{"rendered":"<p>Quick Answer: Choose a reversing contactor by matching its AC-3 rating to the motor&#8217;s full-load current at the actual supply voltage. Then confirm coil voltage, three-pole<span class=\"excerpt-hellip\"> [\u2026]<\/span><\/p>\n","protected":false},"author":1,"featured_media":8980,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[153],"tags":[137,162,158,136,135],"class_list":["post-8983","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-ac-contactor","tag-abb","tag-allen-bradley","tag-mitsubishi","tag-schneider","tag-siemens"],"_links":{"self":[{"href":"https:\/\/www.simplybuyglobal.com\/de\/wp-json\/wp\/v2\/posts\/8983","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.simplybuyglobal.com\/de\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.simplybuyglobal.com\/de\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.simplybuyglobal.com\/de\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.simplybuyglobal.com\/de\/wp-json\/wp\/v2\/comments?post=8983"}],"version-history":[{"count":1,"href":"https:\/\/www.simplybuyglobal.com\/de\/wp-json\/wp\/v2\/posts\/8983\/revisions"}],"predecessor-version":[{"id":9123,"href":"https:\/\/www.simplybuyglobal.com\/de\/wp-json\/wp\/v2\/posts\/8983\/revisions\/9123"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.simplybuyglobal.com\/de\/wp-json\/wp\/v2\/media\/8980"}],"wp:attachment":[{"href":"https:\/\/www.simplybuyglobal.com\/de\/wp-json\/wp\/v2\/media?parent=8983"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.simplybuyglobal.com\/de\/wp-json\/wp\/v2\/categories?post=8983"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.simplybuyglobal.com\/de\/wp-json\/wp\/v2\/tags?post=8983"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}