{"id":3646,"date":"2026-08-15T01:00:00","date_gmt":"2026-08-15T01:00:00","guid":{"rendered":"https:\/\/chac-electric.com\/blog\/dc-contactor-load-polarity-rfq\/"},"modified":"2026-08-15T04:31:11","modified_gmt":"2026-08-15T04:31:11","slug":"dc-contactor-load-polarity-rfq","status":"publish","type":"post","link":"https:\/\/chac-electric.com\/es\/blog\/dc-contactor-load-polarity-rfq\/","title":{"rendered":"What Should a DC Contactor RFQ Say About Load Polarity?"},"content":{"rendered":"<div class=\"b2b-article\">\n<p style=\"margin:0 0 16px;line-height:1.7\">A DC contactor RFQ becomes easier to review when it names <strong>load polarity<\/strong> and <strong>coil polarity<\/strong> separately. Add the working voltage, current, application, switching duty, and the exact product record alongside those fields; otherwise a reply can look complete while still leaving the circuit question unanswered.<\/p>\n<figure style=\"margin:26px 0;text-align:center\"><img decoding=\"async\" style=\"max-width:640px;width:100%;height:auto;display:block;margin:0 auto;border-radius:8px\" alt=\"STE2 high-voltage DC contactor for load-polarity document review\" src=\"https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/08\/STE2-Series-High-voltage-DC-contactor.1.webp\" \/><\/figure>\n<ul style=\"margin:0 0 18px 1.2em;line-height:1.7\">\n<li style=\"margin:0 0 8px\">Frequently Asked Questions: DC Contactor Polarity<\/li>\n<\/ul>\n<nav class=\"b2b-toc\" style=\"background:#f5f8fa;padding:16px 20px;border-radius:8px;margin:0 0 24px\">\n<h2 id=\"contents\" style=\"margin:42px 0 14px;scroll-margin-top:96px\">\u00cdndice<\/h2>\n<ul style=\"margin:0 0 18px 1.2em;line-height:1.7\">\n<li style=\"margin:0 0 8px\"><a href=\"#part-1-separate-the-two-polarity-questions-before-reviewing-a-contactor\">Part 1. Separate the two polarity questions before reviewing a contactor<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-2-read-the-product-record-without-inferring-terminal-behaviour\">Part 2. Read the product record without inferring terminal behaviour<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-3-build-the-circuit-context-around-the-polarity-field\">Part 3. Build the circuit context around the polarity field<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-4-turn-polarity-into-a-reviewable-rfq-line\">Part 4. Turn polarity into a reviewable RFQ line<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-5-where-the-ste2-product-page-fits-the-record\">Part 5. Where the STE2 product page fits the record<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"#part-6-keep-the-selection-result-inside-its-evidence-boundary\">Part 6. Keep the selection result inside its evidence boundary<\/a><\/li>\n<\/ul>\n<\/nav>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-1-separate-the-two-polarity-questions-before-reviewing-a-contactor\">Part 1. Separate the two polarity questions before reviewing a contactor<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">Load polarity describes the DC side that the main contacts are expected to switch. Coil polarity concerns the control-side coil connection. They answer different questions, so one should never be used as a substitute for the other in a quote request.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">The distinction matters because a product record can state a condition for the load path while the buyer still has a separate control interface to define. The real search question\u2014whether contactor connection direction matters\u2014shows why the RFQ needs both fields before anyone interprets a diagram or a catalogue statement.<\/p>\n<table style=\"width:100%;border-collapse:collapse\">\n<thead>\n<tr>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">RFQ field<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">What it identifies<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">What it does not decide<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Polaridad de carga<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">The polarity requirement for the power circuit<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Coil supply or a project wiring direction<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Polaridad de la bobina<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">The control-side coil connection requirement<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Main-contact load polarity<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Working voltage and current<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">The intended electrical operating point<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Switching duty or approval for a circuit<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Product record<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">The document being reviewed<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">A substitute for the selected configuration<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p style=\"margin:0 0 16px;line-height:1.7\">For a broader application view, CHAC\u2019s <a href=\"https:\/\/chac-electric.com\/es\/aparatos-electricos-de-control-industrial\/\">aparatos el\u00e9ctricos de control industrial<\/a> page is the appropriate product-line starting point. The narrower question here is how to make the polarity request legible to the person reading the RFQ.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-2-read-the-product-record-without-inferring-terminal-behaviour\">Part 2. Read the product record without inferring terminal behaviour<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">Unlike a generic \u201cDC contactor\u201d label, a published product record can describe a specific load-polarity feature or state conditions that belong only to particular entries. That language should be copied into the RFQ as a document reference, not rephrased as a universal instruction about terminal direction.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">Ask for the exact series, configuration, and revision that the buyer wants reviewed. A polarity statement only becomes meaningful when the document, load circuit, and selected contactor option stay together.<\/p>\n<blockquote>\n<p style=\"margin:0 0 16px;line-height:1.7\"><strong>Importante:<\/strong> A selection page is not a circuit approval. <a href=\"https:\/\/schaltbau.com\/en\/industry-insights\/5-criteria-to-consider-when-selecting-a-dc-contactor\/\" rel=\"nofollow noopener\" target=\"_blank\">Schaltbau\u2019s DC contactor selection criteria<\/a> underline that the contactor must be considered against the actual application conditions.<\/p>\n<\/blockquote>\n<p style=\"margin:0 0 16px;line-height:1.7\">This boundary also separates this topic from an <a href=\"https:\/\/chac-electric.com\/es\/blog\/high-voltage-dc-contactor-ev-charging-selection\/\">EV charging DC contactor RFQ<\/a>, which addresses a wider application set. A polarity field is one document-control input, not a complete selection outcome.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-3-build-the-circuit-context-around-the-polarity-field\">Part 3. Build the circuit context around the polarity field<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">Before the polarity entry can be reviewed, describe what the contactor is expected to do in the circuit. Selection guidance repeatedly puts working voltage, current, and application beside the component choice because those inputs change the meaning of a nominal rating.<\/p>\n<figure style=\"margin:26px 0;text-align:center\"><img decoding=\"async\" style=\"max-width:640px;width:100%;height:auto;display:block;margin:0 auto;border-radius:8px\" alt=\"STE2 DC contactor shown for working-voltage and current record review\" src=\"https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/08\/STE2-Series-High-voltage-DC-contactor.2.webp\" \/><\/figure>\n<p style=\"margin:0 0 16px;line-height:1.7\">Use a compact context block rather than a long narrative:<\/p>\n<ul style=\"margin:0 0 18px 1.2em;line-height:1.7\">\n<li style=\"margin:0 0 8px\">application and the switched DC function;<\/li>\n<li style=\"margin:0 0 8px\">working voltage and current at the intended point of use;<\/li>\n<li style=\"margin:0 0 8px\">requested load-polarity statement and separate coil-polarity requirement;<\/li>\n<li style=\"margin:0 0 8px\">number of poles, if the circuit document requires it;<\/li>\n<li style=\"margin:0 0 8px\">switching duty or duty description; and<\/li>\n<li style=\"margin:0 0 8px\">drawing, wiring record, or product-document reference used for review.<\/li>\n<\/ul>\n<p style=\"margin:0 0 16px;line-height:1.7\">Manufacturer selection material from <a href=\"https:\/\/www.hotsoninternational.com\/5-tips-to-choose-suitable-dc-contactor\/\" rel=\"nofollow noopener\" target=\"_blank\">HOTSON<\/a> likewise groups application, voltage, and current inputs. It does not turn a generic rule into a wiring instruction, which is the discipline this RFQ format preserves.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-4-turn-polarity-into-a-reviewable-rfq-line\">Part 4. Turn polarity into a reviewable RFQ line<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">For procurement teams, the practical improvement is not a longer email. It is a line-by-line request in which every field can be traced back to the circuit and product record.<\/p>\n<table style=\"width:100%;border-collapse:collapse\">\n<thead>\n<tr>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">Send with the RFQ<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">Why the reviewer needs it<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f5f8fa;text-align:left\">Example of a bounded entry<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Polaridad de carga<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Identifies the requested load-side condition<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">\u201cLoad-polarity requirement: confirm against named product record\u201d<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Coil polarity and coil supply<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Keeps control information separate<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">\u201cCoil requirement: state separately from load field\u201d<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Working voltage \/ current<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Establishes the intended operating point<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">\u201cState values from the circuit documentation\u201d<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Application and duty<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Gives the contactor-use context<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">\u201cDescribe the switching function and duty\u201d<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Product record and configuration<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">Prevents a series-level assumption<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px\">\u201cAttach selected product page or data record\u201d<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p style=\"margin:0 0 16px;line-height:1.7\">The phrase \u201cconfirm against named product record\u201d deliberately avoids a promise about connection direction. It makes the vendor response auditable: a reviewer can see which information was supplied and which document must answer the configuration question.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">Buyers working with a pre-charge path should keep its separate operating question in view; the related <a href=\"https:\/\/chac-electric.com\/es\/blog\/contactores-de-cc-de-alto-voltaje-ev-pre-carga-rfq\/\">pre-charge RFQ article<\/a> is useful for that context. It should not be used to fill in missing polarity information for a different circuit.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-5-where-the-ste2-product-page-fits-the-record\">Part 5. Where the STE2 product page fits the record<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">CHAC\u2019s <a href=\"https:\/\/chac-electric.com\/es\/product\/ste2-series-high-voltage-dc-contactor-round-epoxy-sealing\/\">STE2 high-voltage DC contactor product record<\/a> is useful when the buyer needs a named series page to attach to a review. The page lists a 12\u20131500 VDC range and a 50\u2013800 A range; it also presents non-polarized load support for specified entries.<\/p>\n<figure style=\"margin:26px 0;text-align:center\"><img decoding=\"async\" style=\"max-width:640px;width:100%;height:auto;display:block;margin:0 auto;border-radius:8px\" alt=\"STE2 DC contactor product record for a scoped RFQ review\" src=\"https:\/\/chac-electric.com\/wp-content\/uploads\/2026\/08\/STE2-Series-High-voltage-DC-contactor-1.webp\" \/><\/figure>\n<p style=\"margin:0 0 16px;line-height:1.7\">That is a documentation benefit, not a project selection claim. The buyer should still identify the requested configuration, circuit data, and application before asking whether the published statement applies to the intended use.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">If an OEM needs product adaptation discussions after that document review, the <a href=\"https:\/\/chac-electric.com\/es\/personalizacion-de-control-industrial\/\">ruta de personalizaci\u00f3n de control industrial<\/a> provides the relevant route. A quote request is more useful when it carries the actual circuit and product-record inputs rather than a single polarity word.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"part-6-keep-the-selection-result-inside-its-evidence-boundary\">Part 6. Keep the selection result inside its evidence boundary<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7\">For the final review, keep polarity as a field to be defined and checked rather than a shortcut to an installation decision. A buyer can request a response against the selected product document, but the resulting reply should not be read as an approval of a terminal arrangement, switching performance, or project design.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7\">When the record is complete, send the scope to CHAC through the <a href=\"https:\/\/chac-electric.com\/es\/contactanos\/\">contact page<\/a> with the product reference and circuit information. When it is incomplete, ask for the missing record first; guessing from a photograph, a series name, or a generic polarity discussion adds ambiguity rather than removing it.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"frequently-asked-questions-dc-contactor-polarity\">Frequently Asked Questions: DC Contactor Polarity<\/h2>\n<h3 style=\"margin:28px 0 12px\">Does DC contactor load polarity matter?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">It can matter to the selected product and circuit, so the RFQ should state the load-polarity requirement rather than assume it from a general DC label. The named product record is the place to review how that requirement is described.<\/p>\n<h3 style=\"margin:28px 0 12px\">Is load polarity the same as coil polarity?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">No. Load polarity refers to the main switched path, while coil polarity concerns the control-side coil connection. Keep them in separate RFQ fields so the reviewer does not need to infer one from the other.<\/p>\n<h3 style=\"margin:28px 0 12px\">Which details belong beside a polarity request?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">Provide the intended application, working voltage, working current, duty description, requested product configuration, and the circuit or product document used for review. Those details make a polarity request actionable.<\/p>\n<h3 style=\"margin:28px 0 12px\">Does a non-polarized load statement apply to every contactor?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">No. Treat that wording as a scoped product-record statement. Confirm the selected series entry and configuration instead of extending it to every contactor or every project.<\/p>\n<h3 style=\"margin:28px 0 12px\">Can a product page replace a circuit drawing review?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">No. A product page can identify published features and ranges, but it does not show the buyer\u2019s circuit conditions or approve a connection arrangement. Keep the relevant circuit record with the RFQ.<\/p>\n<h3 style=\"margin:28px 0 12px\">What information should be sent for a quote review?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7\">Send the requested load-polarity and coil-polarity fields, the working voltage and current, application and duty description, product reference, configuration, and available circuit documentation. That gives the reviewer a bounded set of inputs to assess.<\/p>\n<h2 style=\"margin:42px 0 14px;scroll-margin-top:96px\" id=\"references\">Referencias<\/h2>\n<ul style=\"margin:0 0 18px 1.2em;line-height:1.7\">\n<li style=\"margin:0 0 8px\"><a href=\"https:\/\/schaltbau.com\/en\/industry-insights\/5-criteria-to-consider-when-selecting-a-dc-contactor\/\" rel=\"nofollow noopener\" target=\"_blank\">Schaltbau: Five criteria to consider when selecting a DC contactor<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"https:\/\/viox.com\/how-to-choose-a-dc-contactor\/\" rel=\"nofollow noopener\" target=\"_blank\">VIOX: How to choose a DC contactor<\/a><\/li>\n<li style=\"margin:0 0 8px\"><a href=\"https:\/\/www.hotsoninternational.com\/5-tips-to-choose-suitable-dc-contactor\/\" rel=\"nofollow noopener\" target=\"_blank\">HOTSON: Five tips to choose a suitable DC contactor<\/a><\/li>\n<\/ul>\n<\/div>","protected":false},"excerpt":{"rendered":"<p>A DC contactor RFQ becomes easier to review when it names load polarity and coil polarity separately. Add the working voltage, current, application, switching duty, and the exact product record alongside those fields; otherwise a reply can look complete while still leaving the circuit question unanswered. Frequently Asked Questions: DC Contactor Polarity Contents Part 1. [&hellip;]<\/p>\n","protected":false},"author":10,"featured_media":3480,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[],"class_list":["post-3646","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\/3646","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=3646"}],"version-history":[{"count":1,"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/posts\/3646\/revisions"}],"predecessor-version":[{"id":3648,"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/posts\/3646\/revisions\/3648"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/media\/3480"}],"wp:attachment":[{"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/media?parent=3646"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/categories?post=3646"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/chac-electric.com\/es\/wp-json\/wp\/v2\/tags?post=3646"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}