{"product_id":"kw12-3-roller-lever-micro-limit-switch-pcb-terminals-10pcs","title":"10pcs KW12-3 Roller Lever Micro Limit Switch PCB Terminals NO\/NC","description":"\n\u003ch2\u003eKW12-3 Roller Lever Arm Micro Limit Switches — 10-Pack with PCB Terminals\u003c\/h2\u003e\n\u003cp\u003eKeep your electronics and automation projects running smoothly with this convenient 10-pack of KW12-3 Roller Lever Arm Micro Limit Switches. Featuring both Normally Open (NO) and Normally Close (NC) configurations, these compact PCB-mount switches deliver fast, reliable switching action in a wide range of applications — from DIY robotics and 3D printers to home appliances and industrial controls.\u003c\/p\u003e\n\n\u003ch3\u003eKey Features\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eDual Configuration:\u003c\/strong\u003e Supports Normal Open (NO) and Normal Close (NC) operation for versatile wiring options\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRoller Lever Arm:\u003c\/strong\u003e Smooth-rolling lever ensures consistent, repeatable mechanical actuation\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePCB Terminal Mounting:\u003c\/strong\u003e Direct circuit board solder terminals for a clean, secure installation\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWide Temperature Range:\u003c\/strong\u003e Operates reliably from -40°C to 70°C (-40°F to 158°F)\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eRated Voltage:\u003c\/strong\u003e AC 125V – 250V\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCurrent Rating:\u003c\/strong\u003e 5A\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eCompact Size:\u003c\/strong\u003e 20 × 10 × 6 mm (L × W × H) — fits tight spaces with ease\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePlastic Housing:\u003c\/strong\u003e Lightweight and durable construction\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eValue Pack:\u003c\/strong\u003e 10 switches per order — great for prototyping, repairs, and bulk builds\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eHow It Works\u003c\/h3\u003e\n\u003cp\u003eThe KW12-3 micro limit switch uses an external mechanical force transmitted through its roller lever arm to act on an internal spring reed. When the force reaches a critical threshold, the reed snaps instantaneously — rapidly making or breaking the electrical circuit. When the force is removed, the spring reverses the action just as quickly. This snap-action mechanism delivers a small contact gap, short stroke, low actuation force, and ultra-fast switching response.\u003c\/p\u003e\n\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eModel\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eKW12-3\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eSwitch Type\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eMicro Limit Switch (Roller Lever Arm)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCircuit\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eNormal Open \/ Normal Close (NO\/NC)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTerminal Type\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003ePCB Mount Solder Terminals\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eRated Voltage\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eAC 125V – 250V\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCurrent Rating\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e5A\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOperating Temperature\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e-40°C to 70°C\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eBody Material\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003ePlastic\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eDimensions\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e20 × 10 × 6 mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eQuantity\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e10 pieces\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCountry of Origin\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eMade in China\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eCommon Applications\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e3D printers (endstop \/ homing switches)\u003c\/li\u003e\n  \u003cli\u003eCNC machines and robotics\u003c\/li\u003e\n  \u003cli\u003eComputer mice and peripheral devices\u003c\/li\u003e\n  \u003cli\u003eAutomotive electronics\u003c\/li\u003e\n  \u003cli\u003eCommunications equipment\u003c\/li\u003e\n  \u003cli\u003eGas water heaters and gas burners\u003c\/li\u003e\n  \u003cli\u003eSmall home appliances, microwave ovens, and electric rice cookers\u003c\/li\u003e\n  \u003cli\u003eFloating ball and level-sensing equipment\u003c\/li\u003e\n  \u003cli\u003eBuilding automation and electric tools\u003c\/li\u003e\n  \u003cli\u003eTest instruments and industrial controls\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003ePackage Contents\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e10 × KW12-3 Roller Lever Micro Limit Switches\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003cp\u003eLearn more: \u003ca href=\"https:\/\/www.osha.gov\/eye-face-protection\" target=\"_blank\" rel=\"noopener\"\u003eOSHA on eye and face protection\u003c\/a\u003e\u003c\/p\u003e\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003ch4\u003eQ: What is the difference between the Normal Open (NO) and Normal Close (NC) terminals on the KW12-3 micro limit switch?\u003c\/h4\u003e\n\u003cp\u003eA: The KW12-3 switch has three PCB terminals: Common (COM), Normally Open (NO), and Normally Close (NC). In its resting state, the COM and NC terminals are connected (circuit closed), while COM and NO are disconnected (circuit open). When the roller lever is actuated, the circuit switches — COM connects to NO and disconnects from NC. This lets you choose either configuration depending on your circuit design.\u003c\/p\u003e\n\n\u003ch4\u003eQ: Are these KW12-3 micro limit switches compatible with 3D printer endstops?\u003c\/h4\u003e\n\u003cp\u003eA: Yes! The KW12-3 roller lever micro limit switch is one of the most widely used endstop switches in 3D printers (such as those running RAMPS or similar boards). Their compact PCB terminal format, snap-action response, and consistent actuation make them an ideal drop-in replacement or upgrade for standard printer endstop positions.\u003c\/p\u003e\n\n\u003ch4\u003eQ: What voltage and current can the KW12-3 micro limit switch handle?\u003c\/h4\u003e\n\u003cp\u003eA: Each KW12-3 switch is rated for AC 125V to 250V at up to 5A. They are suitable for both low-voltage signal circuits (such as microcontroller inputs) and higher-voltage switching applications within the rated limits. Always ensure your application stays within the specified electrical ratings for safe, reliable operation.\u003c\/p\u003e\n\n\u003ch4\u003eQ: How are these switches mounted to a circuit board?\u003c\/h4\u003e\n\u003cp\u003eA: The KW12-3 features three through-hole PCB solder terminals (COM, NO, NC) on the bottom of the housing. Simply insert the terminals into matching holes on your PCB and solder them in place for a secure, permanent connection. No additional connectors or adapters are required for direct board mounting.\u003c\/p\u003e\n\u003c!-- production-packaging-notice --\u003e\n\u003ch3\u003eProduction \u0026amp; Packaging Notice\u003c\/h3\u003e\n\u003cp\u003eTo maintain high stock availability and fast shipping times, our items are sourced from multiple verified manufacturing facilities. While the core quality, materials, and product specifications remain identical, you may notice slight variations in the packaging design, manufacturing origin, or the wording of the printed instructions.\u003c\/p\u003e\n\u003cscript type=\"application\/ld+json\"\u003e{\"@context\": \"https:\/\/schema.org\", \"@type\": \"FAQPage\", \"mainEntity\": [{\"@type\": \"Question\", \"name\": \"What is the difference between the Normal Open (NO) and Normal Close (NC) terminals on the KW12-3 micro limit switch?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"The KW12-3 switch has three PCB terminals: Common (COM), Normally Open (NO), and Normally Close (NC). In its resting state, the COM and NC terminals are connected (circuit closed), while COM and NO are disconnected (circuit open). When the roller lever is actuated, the circuit switches — COM connects to NO and disconnects from NC. 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No additional connectors or adapters are required for direct board mounting.\"}}]}\u003c\/script\u003e\n\u003cscript type=\"application\/ld+json\"\u003e{\"@context\": \"https:\/\/schema.org\", \"@type\": \"BreadcrumbList\", \"itemListElement\": [{\"@type\": \"ListItem\", \"position\": 1, \"name\": \"Home\", \"item\": \"https:\/\/0dwbi8-fa.myshopify.com\/\"}, {\"@type\": \"ListItem\", \"position\": 2, \"name\": \"Home page\", \"item\": \"https:\/\/0dwbi8-fa.myshopify.com\/collections\/frontpage\"}, {\"@type\": \"ListItem\", \"position\": 3, \"name\": \"10pcs KW12-3 Roller Lever Micro Limit Switch PCB Terminals NO\/NC\", \"item\": \"https:\/\/0dwbi8-fa.myshopify.com\/products\/kw12-3-roller-lever-micro-limit-switch-pcb-terminals-10pcs\"}]}\u003c\/script\u003e","brand":"Quake","offers":[{"title":"Default Title","offer_id":50286589444323,"sku":"\u003cnone\u003e","price":12.22,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0820\/9439\/1523\/files\/He9508c76dd4b448f8baafa02b7b545ecn.webp?v=1790289911","url":"https:\/\/quakegoods.com\/products\/kw12-3-roller-lever-micro-limit-switch-pcb-terminals-10pcs","provider":"Quake","version":"1.0","type":"link"}