{"id":884,"date":"2026-07-11T21:15:50","date_gmt":"2026-07-11T13:15:50","guid":{"rendered":"https:\/\/lemaele.com\/blog\/spdt-limit-switch-selection-guide\/"},"modified":"2026-07-24T17:12:52","modified_gmt":"2026-07-24T09:12:52","slug":"spdt-limit-switch-selection-guide","status":"publish","type":"post","link":"https:\/\/lemaele.com\/pt\/blog\/spdt-limit-switch-selection-guide\/","title":{"rendered":"SPDT Limit Switch: Wiring, Selection and OEM Applications"},"content":{"rendered":"<div class=\"b2b-article\" style=\"max-width:820px;margin:0 auto;\">\n<p style=\"margin:0 0 16px;line-height:1.7;\">An <strong><strong>SPDT limit switch<\/strong><\/strong> (single pole, double throw) routes one common terminal to either a normally open or normally closed contact, making it common in interlocks, position sensing, and dual-indicator control circuits. OEM engineers in the United States and Canada specify SPDT limit switches when one actuator must drive two logic paths or when maintenance teams need flexible wiring during retrofit. This guide explains contact behavior, wiring conventions, and documentation to request before AVL approval. This guide focuses on practical evaluation steps for U.S. and Canadian OEM buyers\u2014specifications, sample qualification, and documentation\u2014not generic marketing claims. Cross-check public specifications on lemaele.com and confirm project-specific ratings with your design engineer and <a href=\"https:\/\/lemaele.com\/contact-us\/\">LEMA Electric<\/a> before production release. Section checklists can be reused as RFQ attachments and supplier audit outlines.<\/p>\n<nav style=\"background:#f7f9fb;border:1px solid #e3e8ee;border-radius:8px;padding:14px 18px;margin:0 0 24px;\">\n<p style=\"margin:0 0 16px;line-height:1.7;\"><strong>On this page<\/strong><\/p>\n<ul style=\"margin:0 0 18px 1.2em;line-height:1.7;\">\n<li style=\"margin:0 0 16px;line-height:1.7;\"><a href=\"#part-1-spdt-contact-behavior-and-typical-circuit\">Part 1. SPDT Contact Behavior and Typical Circuits<\/a><\/li>\n<li style=\"margin:0 0 16px;line-height:1.7;\"><a href=\"#part-2-key-specifications-and-comparison-points\">Part 2. Key Specifications and Comparison Points<\/a><\/li>\n<li style=\"margin:0 0 16px;line-height:1.7;\"><a href=\"#part-3-oem-qualification-and-sourcing\">Part 3. OEM Qualification and Sourcing<\/a><\/li>\n<li style=\"margin:0 0 16px;line-height:1.7;\"><a href=\"#part-4-documentation-and-handover-checklist\">Part 4. Documentation and Handover Checklist<\/a><\/li>\n<li style=\"margin:0 0 16px;line-height:1.7;\"><a href=\"#part-5-sample-qualification-field-service-and-li\">Part 5. Sample Qualification, Field Service, and Lifecycle Support<\/a><\/li>\n<\/ul>\n<\/nav>\n<figure style=\"margin:26px 0;text-align:center;\"><img loading=\"lazy\" decoding=\"async\" style=\"max-width:640px;width:100%;height:auto;display:block;margin:0 auto;border-radius:8px;\" src=\"https:\/\/lemaele.com\/wp-content\/uploads\/2026\/05\/LZ5-series-sealed-limit-switch.2.webp\" alt=\"SPDT limit switch wiring concept illustration (not a product photo)\" width=\"640\" height=\"360\" title=\"\"><\/figure>\n<h2 id=\"part-1-spdt-contact-behavior-and-typical-circuit\" style=\"margin:42px 0 14px;font-size:1.35em;line-height:1.3;\">Part 1. SPDT Contact Behavior and Typical Circuits<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7;\">In SPDT switches, the common (COM) terminal connects to NC when the actuator is released and transfers to NO at the tripped position\u2014or the opposite depending on series design.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Safety circuits often use NC contacts so an open circuit stops motion; signal circuits may use NO for PLC inputs\u2014confirm logic before panel wiring.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Some limit switches offer snap-action SPDT blocks with positive opening on NC contacts for certain safety categories\u2014verify series documentation.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Map the switch series to equipment category\u2014appliance, industrial machine, automotive aftermarket, or control panel\u2014before finalizing AVL.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Environmental exposure (dust, wash-down, outdoor) should drive IP class and material choices as early as actuator selection.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Browse related series on <a href=\"https:\/\/lemaele.com\/limit-switch\/\">LEMA Electric limit switch catalog<\/a> when multiple switch types appear in one BOM.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Include actuator type, terminal style, and load profile in the RFQ package to reduce sample iteration cycles.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Align switch series selection with mechanical fixture design before tooling freeze on OEM programs.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Define acceptance tests\u2014operating force, contact resistance, and release point\u2014before approving a supplier lot.<\/p>\n<div class=\"tip-box\" style=\"border-left:4px solid #2e7d32;background:#f3faf4;padding:12px 16px;margin:0 0 18px;line-height:1.7;\"><strong>Tip:<\/strong> Label COM\/NO\/NC on schematics with the same terminal IDs used on the switch body to reduce field wiring errors.<\/div>\n<h2 id=\"part-2-key-specifications-and-comparison-points\" style=\"margin:42px 0 14px;font-size:1.35em;line-height:1.3;\">Part 2. Key Specifications and Comparison Points<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Rated current and voltage must match continuous and inrush loads; inductive loads may require contact material suited to arcing.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Actuator style (roller, plunger, rod) affects approach angle and mechanical life on conveyors, guards, and machine beds.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Enclosure IP class and conduit entry orientation matter for wash-down lines and outdoor equipment.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Integration teams should confirm wire gauge, bend radius, and strain relief compatible with chosen terminals.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">For high-cycle applications, plan inspection intervals based on mechanical life data at rated current.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Document NC\/NO assignment and wire colors in schematics to reduce field wiring errors during service.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Include actuator type, terminal style, and load profile in the RFQ package to reduce sample iteration cycles.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Align switch series selection with mechanical fixture design before tooling freeze on OEM programs.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Define acceptance tests\u2014operating force, contact resistance, and release point\u2014before approving a supplier lot.<\/p>\n<table style=\"width:100%;border-collapse:collapse;margin:0 0 20px;\">\n<thead>\n<tr>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f4f7fa;text-align:left;\">Parameter<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f4f7fa;text-align:left;\">Why it matters<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f4f7fa;text-align:left;\">Buyer question<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Contact form (SPDT)<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Wiring flexibility<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Which pole is NC at rest?<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Rated current\/voltage<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Safety margin<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Continuous vs inrush?<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Actuator type<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Integration<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Roller vs plunger for approach angle?<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Mechanical life<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Maintenance<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Cycles at rated load?<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">IP rating<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Environment<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Full-body or actuator-only seal?<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<figure style=\"margin:26px 0;text-align:center;\"><img loading=\"lazy\" decoding=\"async\" style=\"max-width:640px;width:100%;height:auto;display:block;margin:0 auto;border-radius:8px;\" src=\"https:\/\/lemaele.com\/wp-content\/uploads\/2026\/05\/LZ1-Limit-Switch.2.webp\" alt=\"Spdt Limit Switch \u2014 LEMA Electric official product with illustrative industrial background (not a real site photo)\" width=\"640\" height=\"360\" title=\"\"><\/figure>\n<div class=\"warning-box\" style=\"border-left:4px solid #f9a825;background:#fffbf0;padding:12px 16px;margin:0 0 18px;line-height:1.7;\"><strong>Important:<\/strong> Do not exceed rated current, voltage, or temperature without manufacturer confirmation\u2014derating may be required for inductive loads or enclosed panels.<\/div>\n<h2 id=\"part-3-oem-qualification-and-sourcing\" style=\"margin:42px 0 14px;font-size:1.35em;line-height:1.3;\">Part 3. OEM Qualification and Sourcing<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Run samples through your fixture at min\/max temperature and verify transfer point, contact resistance, and NC\/NO continuity.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">For export equipment, confirm UL or recognized component scope for the exact SPDT block and actuator combination.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Maintain internal part numbers tied to actuator geometry so field service orders the same limit switch variant.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Procurement should lock revision-controlled part numbers after sample approval to prevent unqualified substitutions.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Keep a replacement guide with equivalent actuator geometry for maintenance teams.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Submit application notes via <a href=\"https:\/\/lemaele.com\/contact-us\/\">LEMA Electric engineering contact<\/a> when standard catalog actuators do not fit the mechanical layout.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Include actuator type, terminal style, and load profile in the RFQ package to reduce sample iteration cycles.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Align switch series selection with mechanical fixture design before tooling freeze on OEM programs.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Define acceptance tests\u2014operating force, contact resistance, and release point\u2014before approving a supplier lot.<\/p>\n<div class=\"tip-box\" style=\"border-left:4px solid #2e7d32;background:#f3faf4;padding:12px 16px;margin:0 0 18px;line-height:1.7;\"><strong>Tip:<\/strong> Compare competing SPDT limit switches using identical cam speed and load\u2014not nameplate life alone.<\/div>\n<div class=\"tip-box\" style=\"border-left:4px solid #2e7d32;background:#f3faf4;padding:12px 16px;margin:0 0 18px;line-height:1.7;\"><strong>Tip:<\/strong> Store approved datasheets with revision dates next to internal part numbers in your PLM or AVL system.<\/div>\n<h2 id=\"part-4-documentation-and-handover-checklist\" style=\"margin:42px 0 14px;font-size:1.35em;line-height:1.3;\">Part 4. Documentation and Handover Checklist<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7;\">OEM acceptance should not rely on visual inspection alone\u2014documentation proves ratings, actuator variant, and compliance scope for each lot.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Use the tables below as a starting RFQ checklist; your quality system may require additional PPAP or inspection items.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">For product-specific datasheets, cross-check <a href=\"https:\/\/lemaele.com\/limit-switch\/\">related LEMA Electric product pages<\/a> and request missing type test excerpts.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">When comparing quotations, normalize currency, Incoterms, sample charges, and included compliance documents before ranking suppliers.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Align incoming inspection with tests your QA team can repeat\u2014operating force, contact resistance, and dielectric checks where applicable.<\/p>\n<table style=\"width:100%;border-collapse:collapse;margin:0 0 20px;\">\n<thead>\n<tr>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f4f7fa;text-align:left;\">Document \/ item<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f4f7fa;text-align:left;\">Purpose<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f4f7fa;text-align:left;\">When to request<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Factory type test report<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Verify rated current\/voltage and mechanical life<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Before purchase order<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Dimensional drawing \/ CAD<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Panel cutout, mounting, and wire exit<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Design phase<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Compliance certificates<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">UL\/CE scope for the exact series<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Before AVL approval<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Sample inspection criteria<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Operating force, contact resistance, sealing<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Before first production lot<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Spare parts list<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Field service and critical replacements<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Contract negotiation<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<table style=\"width:100%;border-collapse:collapse;margin:0 0 20px;\">\n<thead>\n<tr>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f4f7fa;text-align:left;\">Application<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f4f7fa;text-align:left;\">Typical actuator<\/th>\n<th style=\"border:1px solid #d9e1e8;padding:9px 12px;background:#f4f7fa;text-align:left;\">Selection note<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Conveyors<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Roller lever<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Side approach vs top approach affects lever length<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Elevators<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Door zone \/ final limit<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Confirm safety interlock logic (NC\/NO)<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Machine guards<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Plunger or rod<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Positive opening required for some safety circuits<\/td>\n<\/tr>\n<tr>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Outdoor machinery<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Sealed roller<\/td>\n<td style=\"border:1px solid #d9e1e8;padding:9px 12px;vertical-align:top;\">Specify IP class for actuator and body<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<div class=\"tip-box\" style=\"border-left:4px solid #2e7d32;background:#f3faf4;padding:12px 16px;margin:0 0 18px;line-height:1.7;\"><strong>Tip:<\/strong> Attach approved drawings to purchase orders so suppliers ship the qualified actuator and terminal combination.<\/div>\n<div class=\"tip-box\" style=\"border-left:4px solid #2e7d32;background:#f3faf4;padding:12px 16px;margin:0 0 18px;line-height:1.7;\"><strong>Tip:<\/strong> Confirm imperial and metric dimensions if tooling serves both U.S. and export assembly lines.<\/div>\n<h2 id=\"part-5-sample-qualification-field-service-and-li\" style=\"margin:42px 0 14px;font-size:1.35em;line-height:1.3;\">Part 5. Sample Qualification, Field Service, and Lifecycle Support<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Qualify switch samples on the production fixture at minimum and maximum expected ambient temperature when applications are sensitive to operating force drift.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Functional checks should include contact resistance, insulation if applicable, and correct NC\/NO behavior under simulated fault conditions.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Field service teams need replacement part numbers tied to actuator geometry\u2014document equivalents to reduce machine downtime.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Track early-life failures by lot code; recurring contact wear may indicate load or actuator misalignment rather than switch quality alone.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Schedule a design review with <a href=\"https:\/\/lemaele.com\/contact-us\/\">LEMA Electric<\/a> when upgrading equipment platforms or changing harness suppliers.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Maintain a critical spares list for safety interlocks and high-cycle stations based on lead time, not only unit cost.<\/p>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Revision-control datasheets when suppliers update materials or factory locations\u2014re-qualify if actuator force or terminal plating changes.<\/p>\n<div class=\"tip-box\" style=\"border-left:4px solid #2e7d32;background:#f3faf4;padding:12px 16px;margin:0 0 18px;line-height:1.7;\"><strong>Tip:<\/strong> Log baseline operating and release force measurements during sample approval for future troubleshooting comparisons.<\/div>\n<h2 style=\"margin:42px 0 14px;font-size:1.35em;line-height:1.3;\">Recommended LEMA Electric Products<\/h2>\n<p style=\"margin:0 0 16px;line-height:1.7;\">For project support, explore our <a href=\"https:\/\/lemaele.com\/limit-switch\/\">related product line<\/a>, <a href=\"https:\/\/lemaele.com\/products\/\">full product catalog<\/a>, and <a href=\"https:\/\/lemaele.com\/about-us\/\">OEM\/ODM capabilities<\/a> on lemaele.com.<\/p>\n<figure style=\"margin:26px 0;text-align:center;\"><img loading=\"lazy\" decoding=\"async\" style=\"max-width:640px;width:100%;height:auto;display:block;margin:0 auto;border-radius:8px;\" src=\"https:\/\/lemaele.com\/wp-content\/uploads\/2026\/05\/LZ15-series-micro-switch.4.webp\" alt=\"LEMA Electric limit_switch \u2014 official product photo with illustrative scene background (not a real site photo)\" width=\"640\" height=\"360\" title=\"\"><\/figure>\n<h2 style=\"margin:42px 0 14px;font-size:1.35em;line-height:1.3;\">FAQ<\/h2>\n<h3 style=\"margin:28px 0 10px;font-size:1.15em;line-height:1.35;\">What is Spdt Limit Switch?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Spdt Limit Switch refers to switch products and selection criteria covered in this guide for OEM buyers in the U.S. and Canada.<\/p>\n<h3 style=\"margin:28px 0 10px;font-size:1.15em;line-height:1.35;\">What is the difference between SPST and SPDT?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7;\">SPST has one circuit path; SPDT switches one input between two outputs\u2014confirm which pole your safety or control logic requires.<\/p>\n<h3 style=\"margin:28px 0 10px;font-size:1.15em;line-height:1.35;\">What IP rating should I specify?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Match IP67\/IP68 to wash-down or outdoor exposure; confirm actuator-only vs full-body sealing.<\/p>\n<h3 style=\"margin:28px 0 10px;font-size:1.15em;line-height:1.35;\">What certifications matter in North America?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7;\">UL or recognized component listings for the exact series and configuration are commonly required.<\/p>\n<h3 style=\"margin:28px 0 10px;font-size:1.15em;line-height:1.35;\">How do actuator types affect integration?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Lever, roller, and plunger styles change mounting envelope, force, and travel\u2014align with fixture design early.<\/p>\n<h3 style=\"margin:28px 0 10px;font-size:1.15em;line-height:1.35;\">What documentation belongs in an OEM RFQ?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Datasheets, drawings, compliance certificates, MOQ\/lead time, and inspection criteria.<\/p>\n<h3 style=\"margin:28px 0 10px;font-size:1.15em;line-height:1.35;\">Can switches be customized with wire leads?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7;\">Many manufacturers offer lead length options\u2014confirm tooling, MOQ, and sample approval.<\/p>\n<h3 style=\"margin:28px 0 10px;font-size:1.15em;line-height:1.35;\">When should I contact the manufacturer directly?<\/h3>\n<p style=\"margin:0 0 16px;line-height:1.7;\">When catalog ratings do not cover your voltage, temperature, or sealing requirements.<\/p>\n<h2 style=\"margin:42px 0 14px;font-size:1.35em;line-height:1.3;\">References<\/h2>\n<ul style=\"margin:0 0 18px 1.2em;line-height:1.7;\">\n<li><a href=\"https:\/\/www.globalspec.com\/learnmore\/electrical_electronic_components\/switches\" rel=\"nofollow noopener\" target=\"_blank\">GlobalSpec \u2014 Switches<\/a><\/li>\n<li><a href=\"https:\/\/www.ul.com\/resources\/standards\" rel=\"nofollow noopener\" target=\"_blank\">UL Standards resources<\/a><\/li>\n<li><a href=\"https:\/\/lemaele.com\/limit-switch\/\" rel=\"nofollow noopener\">LEMA Electric \u2014 Product category<\/a><\/li>\n<\/ul>\n<p style=\"margin:0 0 16px;line-height:1.7;\"><strong>Ready to discuss your project?<\/strong> Contact <a href=\"https:\/\/lemaele.com\/contact-us\/\">LEMA Electric engineering support<\/a> with your project parameters and technical requirements.<\/p>\n<\/div>\n<p><script type=\"application\/ld+json\">{\"@context\": \"https:\/\/schema.org\", \"@type\": \"FAQPage\", \"mainEntity\": [{\"@type\": \"Question\", \"name\": \"What is Spdt Limit Switch?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"Spdt Limit Switch refers to switch products and selection criteria covered in this guide for OEM buyers in the U.S. and Canada.\"}}, {\"@type\": \"Question\", \"name\": \"What is the difference between SPST and SPDT?\", \"acceptedAnswer\": {\"@type\": \"Answer\", \"text\": \"SPST has one circuit path; 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