{"id":1773,"date":"2026-10-01T19:10:00","date_gmt":"2026-10-01T11:10:00","guid":{"rendered":"https:\/\/lemaele.com\/blog\/micro-switch-terminal-types-guide\/"},"modified":"2026-10-06T17:20:41","modified_gmt":"2026-10-06T09:20:41","slug":"micro-switch-terminal-types-guide","status":"publish","type":"post","link":"https:\/\/lemaele.com\/es\/blog\/micro-switch-terminal-types-guide\/","title":{"rendered":"Micro Switch Terminal Types: Solder, PCB and Quick Connect"},"content":{"rendered":"<style>.lema-article{min-width:0;max-width:100%}.lema-article img{max-width:100%;height:auto}.lema-article figure{margin:24px 0}.lema-table-wrap{max-width:100%;overflow-x:auto}.lema-table-wrap table{min-width:640px;border-collapse:collapse}.lema-table-wrap th,.lema-table-wrap td{border:1px solid #ddd;padding:12px;text-align:left}.lema-video{position:relative;padding-bottom:56.25%;height:0}.lema-video iframe{position:absolute;inset:0;width:100%;height:100%;border:0}.single-post article{min-width:0;max-width:100%}<\/style>\n<div class=\"lema-article\">\n<p>Micro switch terminal types should be selected around the assembly process and circuit duty. Solder terminals suit a controlled wire-soldering process, PCB pins suit a verified board footprint and mechanical support, and quick-connect tabs suit an approved mating receptacle and harness. The terminal style does not identify common, normally open or normally closed contacts, and it does not by itself establish current capacity. Choose the complete switch variant, mating parts and termination method together.<\/p>\n<p>This guide addresses connection design for OEM mechanisms using snap-action micro switches. It complements contact identification and multimeter testing rather than replacing them. The LEMA KW7 family provides a real product reference for the photographs; confirm the exact terminal variant on the order drawing before specifying a production connection.<\/p>\n<h2>Separate terminal form from contact function<\/h2>\n<p>A three-terminal snap-action switch often provides common, normally open and normally closed contacts, but those functions must be established from the specific diagram. A blade, solder lug or PCB pin can serve any of the contact functions. Do not assign function from terminal length, location or a photograph of another model.<\/p>\n<p>Create two records: a physical terminal drawing and an electrical state table. The first identifies dimensions, spacing, orientation and permitted connection technique. The second records continuity at released and operated positions. Keep both with the harness documentation. When the production variant changes, verify both records rather than assuming that a familiar housing means the same pin arrangement.<\/p>\n<h2>Solder lugs require heat and strain control<\/h2>\n<p>A solder lug gives a wire a defined attachment point, sometimes with an opening that supports positioning. Confirm whether the maker permits wire wrapping, the specified soldering temperature and duration, and the wire size compatible with the terminal. Excessive heat can travel into the housing or affect the internal construction. A neat-looking joint is not proof that the soldering process was acceptable.<\/p>\n<p>Provide slack and independent wire support so routine movement does not flex the joint. The historical NASA soldered-connections reference illustrates the importance of supported terminations. It is background guidance, not a requirement that every OEM use an aerospace process. Establish the applicable workmanship criteria, solder alloy, cleaning procedure and inspection method for the actual assembly.<\/p>\n<figure><img decoding=\"async\" src=\"https:\/\/lemaele.com\/wp-content\/uploads\/2026\/10\/lema-backfill-micro-switch-terminal-types-guide-body1-20261006.webp\" alt=\"KW7 micro switch terminals beside unmated receptacles and solder wire\" title=\"KW7 micro switch terminals beside unmated receptacles and solder wire\" loading=\"lazy\"><figcaption>KW7 micro switch terminals beside unmated receptacles and solder wire. Product-reference illustration; not a dimensioned drawing, installation instruction or test result.<\/figcaption><\/figure>\n<h2>PCB pins need a footprint and a mechanical plan<\/h2>\n<p>Use a model-specific footprint with the correct pin pitch, pin section and hole sizes. Account for component tolerances, finished hole plating and the soldering process. A switch that can be forced into an approximate hole pattern should not be treated as compatible. Distorted pins can preload the housing or leave unreliable solder joints.<\/p>\n<p>Decide how actuator forces reach the machine structure. PCB pins are electrical terminations; they should not automatically be expected to carry every push or roller load. Use mounting features or a bracket where the approved design requires support. Verify board deflection at the switch during full actuation, including motion beyond the operating point but within the permitted travel.<\/p>\n<h2>Quick-connect tabs are a matched connection system<\/h2>\n<p>A quick-connect tab must mate with a receptacle selected for its width, thickness, material and retention features. Similar nominal widths are insufficient if the contact thickness or required receptacle design differs. Ask for the approved mating terminal information, and document the crimp tooling and conductor range for the harness receptacle.<\/p>\n<p>Check that an operator can seat and remove the connector without levering against the switch case. Provide access for the approved release tool where applicable. Insulation sleeves should cover the required exposed areas without preventing full mating. Do not stack multiple receptacles or repeatedly bend a tab to clear the harness unless the component instructions specifically support that construction.<\/p>\n<div class=\"lema-table-wrap\">\n<table>\n<thead>\n<tr>\n<th>Terminal option<\/th>\n<th>Design evidence<\/th>\n<th>Acceptance focus<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Solder lug<\/td>\n<td>Permitted heat exposure and wire attachment<\/td>\n<td>Joint condition and strain relief<\/td>\n<\/tr>\n<tr>\n<td>PCB pin<\/td>\n<td>Exact footprint and mounting support<\/td>\n<td>Solder quality and board deflection<\/td>\n<\/tr>\n<tr>\n<td>Quick-connect tab<\/td>\n<td>Tab dimensions and approved receptacle<\/td>\n<td>Crimp quality, seating and retention<\/td>\n<\/tr>\n<tr>\n<td>Prewired cable<\/td>\n<td>Wire specification and permitted routing<\/td>\n<td>Exit support and connector identity<\/td>\n<\/tr>\n<tr>\n<td>Screw terminal if offered<\/td>\n<td>Wire range and maker tightening instruction<\/td>\n<td>Correct conductor preparation and seating<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<h2>Prewired variants move work to the supplier<\/h2>\n<p>A prewired micro switch can remove a factory termination step and may simplify assembly in a cramped mechanism. It also introduces cable length, insulation, conductor size, exit direction and strain-relief requirements that must appear in the order specification. Verify the intended connector at the far end and how the cable is retained throughout its route.<\/p>\n<p>Treat a prewired sealed variant as a complete construction. Cutting the cable, replacing its end connector or potting the exit yourself can change relevant environmental or service assumptions. Ask which modifications are permitted. NASA&#8217;s harness workmanship standard is a useful framework for documenting interconnect work, while the exact switch and cable instructions govern the selected product.<\/p>\n<h2>Choose for signal duty and power duty separately<\/h2>\n<p>The physical connection must suit the circuit, but switch contact performance also depends on the internal contact specification. A terminal able to accept a relatively large conductor does not prove that the switch can interrupt a motor, solenoid or other load. Check AC or DC duty, voltage, load character, switching frequency and any minimum-load limitation separately.<\/p>\n<p>For low-level controller signals, identify the input current and voltage and the approved contact option. For a switched load, check startup or inductive behavior and the protection arrangement. A continuity buzzer only establishes a basic state at its test conditions; it cannot validate loaded temperature rise or life. The circuit specification must travel with the terminal selection.<\/p>\n<figure><img decoding=\"async\" src=\"https:\/\/lemaele.com\/wp-content\/uploads\/2026\/10\/lema-backfill-micro-switch-terminal-types-guide-body2-20261006.webp\" alt=\"KW7 micro switches beside isolated connection samples on an inspection bench\" title=\"KW7 micro switches beside isolated connection samples on an inspection bench\" loading=\"lazy\"><figcaption>KW7 micro switches beside isolated connection samples on an inspection bench. Product-reference illustration; not a dimensioned drawing, installation instruction or test result.<\/figcaption><\/figure>\n<h2>Inspect the crimp and the mated pair separately<\/h2>\n<p>A correctly crimped receptacle can still be poorly seated on the switch tab. Conversely, a fully seated connection can hide an unsuitable crimp. Establish separate inspections for conductor preparation, crimp construction, mating depth and retention. Use the selected contact maker&#8217;s tooling, settings and acceptance criteria rather than an unspecified general-purpose tool.<\/p>\n<p>Define which checks are destructive sample tests and which are production inspections. Do not tug on every connection with an improvised force that may damage a sound assembly. If pull testing is required, document the test piece and method. Preserve photographs and a sample of the approved construction so changes in harness production can be detected without relying on memory.<\/p>\n<h2>Plan vibration and maintenance access<\/h2>\n<p>Trace the route from moving cables to the switch terminal. Repeated motion should be absorbed by the intended flexible cable section and support arrangement rather than a solder joint or rigid tab. Avoid a tie placed so close to the housing that it forces the connector sideways. Confirm clearance after covers, guards and neighboring parts are fitted.<\/p>\n<p>Consider service actions as well as normal operation. A technician may need to disconnect the harness without disturbing switch alignment. Mark terminal functions on the drawing and use a connector scheme that reduces confusion when the switch is replaced. If accessibility is poor, a prewired assembly or intermediate connector may be more repeatable than repeated work directly at the switch.<\/p>\n<h2>Investigate an intermittent connection systematically<\/h2>\n<p>On a safely isolated assembly, check whether the discontinuity occurs at the internal contact, terminal joint, mating receptacle or conductor. Operate the actuator within its permitted travel while monitoring the intended contact pair. Then inspect the disconnected termination and cable independently. Preserve the original condition before reworking the connection; replacing everything at once can erase the cause.<\/p>\n<p>Look for incomplete seating, damaged insulation, misplaced strands, unsupported joints, bent pins and contamination. Do not assume that all signal chatter is a loose terminal: contact bounce and repeated mechanical actuation are different mechanisms. Refer to the separate contact-resistance and travel guides when a connection check does not explain the behavior.<\/p>\n<h2>Write a terminal-specific RFQ and release checklist<\/h2>\n<p>Send the complete switch model, circuit state table, drawing revision, chosen terminal style, wire or board details, harness access envelope, soldering or crimp process and operating environment. Ask for permissible assembly loads and temperature exposure. For PCB designs, provide the footprint and supporting features; for a harness, specify the mating receptacle or request a documented recommendation.<\/p>\n<p>At sample approval, compare electrical identity and mechanical fit before performing the relevant connection and operational checks. Record the chosen tools and inspection results. A terminal change can affect the board, harness, assembly time and service procedure even if the switch body remains unchanged. Release the combination of switch, mating connection and production method, not the switch photograph alone.<\/p>\n<h2>Further learning<\/h2>\n<p>This lesson explains electric power. It supports the distinction between a basic continuity check and loaded connection behavior; it does not supply a switch or connector rating.<\/p>\n<div class=\"lema-video\"><iframe src=\"https:\/\/www.youtube-nocookie.com\/embed\/3zt7DWUiaDE\" title=\"Electric power | Circuits | Physics | Khan Academy\" loading=\"lazy\" allow=\"encrypted-media; picture-in-picture\" allowfullscreen><\/iframe><\/div>\n<h2>Related LEMA resources<\/h2>\n<ul>\n<li><a href=\"https:\/\/lemaele.com\/product\/kw7-series-micro-switch\/\">Micro Switch Terminal Types product reference<\/a><\/li>\n<li><a href=\"https:\/\/lemaele.com\/blog\/industrial-micro-switch-selection-guide\/\">Industrial micro switch selection<\/a><\/li>\n<li><a href=\"https:\/\/lemaele.com\/blog\/test-micro-switch-with-multimeter\/\">Isolated micro switch contact testing<\/a><\/li>\n<li><a href=\"https:\/\/lemaele.com\/blog\/micro-switch-contact-resistance-guide\/\">Micro switch contact resistance<\/a><\/li>\n<\/ul>\n<h2>Technical references<\/h2>\n<ul>\n<li><a href=\"https:\/\/standards.nasa.gov\/standard\/NASA\/NASA-STD-87394\" rel=\"noopener\" target=\"_blank\">NASA wiring workmanship standard<\/a>: A reference for controlled cable and harness workmanship; it does not certify the illustrated LEMA part.<\/li>\n<li><a href=\"https:\/\/nepp.nasa.gov\/docuploads\/06AA01BA-FC7E-4094-AE829CE371A7B05D\/NASA-STD-8739.3.pdf\" rel=\"noopener\" target=\"_blank\">NASA soldered connections reference<\/a>: Historical workmanship guidance on supported terminations, used as background rather than a current product approval.<\/li>\n<\/ul>\n<h2>Frequently asked questions<\/h2>\n<h3>Can solder terminals be used as quick-connect tabs?<\/h3>\n<p>Only when the exact manufacturer drawing identifies a compatible mating receptacle. A terminal that resembles a blade may not have the appropriate thickness, retention or mechanical strength. Treat an undocumented substitution as a design change.<\/p>\n<h3>Are PCB terminal switches automatically smaller?<\/h3>\n<p>No. Terminal style and body size are different attributes. Compare the complete housing, actuator envelope, board clearance and support features. A compact body can need more surrounding space when the mechanism and wiring are included.<\/p>\n<h3>Does a heavier wire increase switch current rating?<\/h3>\n<p>No. Conductor selection cannot increase the internal contact rating or justify an unapproved load. Verify the switch duty, mating connector and conductor requirements independently, then validate the installed assembly under its specified conditions.<\/p>\n<h3>What should be recorded when changing terminal variants?<\/h3>\n<p>Record the complete order code, electrical state table, mating parts, harness or PCB revision, assembly process and sample inspection results. Recheck clearance and actuator behavior because a connection change can affect the surrounding mechanical design.<\/p>\n<\/div>\n<p><script type=\"application\/ld+json\">{\"@context\": \"https:\/\/schema.org\", \"@type\": \"FAQPage\", \"mainEntity\": [{\"@type\": \"Question\", \"name\": \"Can solder terminals be used as quick-connect tabs?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Only when the exact manufacturer drawing identifies a compatible mating receptacle. A terminal that resembles a blade may not have the appropriate thickness, retention or mechanical strength. 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Match assembly process, mating parts, strain relief and inspection to the actual circuit.<\/p>","protected":false},"author":9,"featured_media":1770,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[51],"class_list":["post-1773","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","tag-micro-switch"],"_links":{"self":[{"href":"https:\/\/lemaele.com\/es\/wp-json\/wp\/v2\/posts\/1773","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lemaele.com\/es\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lemaele.com\/es\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lemaele.com\/es\/wp-json\/wp\/v2\/users\/9"}],"replies":[{"embeddable":true,"href":"https:\/\/lemaele.com\/es\/wp-json\/wp\/v2\/comments?post=1773"}],"version-history":[{"count":1,"href":"https:\/\/lemaele.com\/es\/wp-json\/wp\/v2\/posts\/1773\/revisions"}],"predecessor-version":[{"id":1774,"href":"https:\/\/lemaele.com\/es\/wp-json\/wp\/v2\/posts\/1773\/revisions\/1774"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/lemaele.com\/es\/wp-json\/wp\/v2\/media\/1770"}],"wp:attachment":[{"href":"https:\/\/lemaele.com\/es\/wp-json\/wp\/v2\/media?parent=1773"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lemaele.com\/es\/wp-json\/wp\/v2\/categories?post=1773"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lemaele.com\/es\/wp-json\/wp\/v2\/tags?post=1773"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}