| Contact Type | SPDT, Form C | One common terminal switches between normally open and normally closed contacts. | Position sensing, safety interlocking, mode selection, and changeover circuits. | A practical choice when one mechanical input must provide both NO and NC outputs. |
| DPDT, Form C × 2 | Two electrically independent SPDT circuits operated by the same actuator. | Polarity reversal, two-channel control, relay substitution, and paired signal switching. | Confirm that both poles have suitable voltage, current, and isolation ratings. |
| SPST-NO or SPST-NC | A single circuit that is either normally open or normally closed. | Simple on/off detection with fewer terminals and straightforward wiring. | Basic limit detection, covers, doors, buttons, and compact control equipment. | Choose NO or NC according to the required fail-safe behavior. |
| Actuator | Pin Plunger | Direct linear actuation; typical overtravel is approximately 0.2–1.5 mm. | Precise end-of-travel detection and fixtures with controlled mechanical alignment. | Requires accurate alignment; avoid side loading on the plunger. |
| Short Lever | Provides moderate mechanical advantage and a compact sensing profile. | General limit switching, machine guards, and small moving mechanisms. | Suitable when the target has limited travel but can contact the lever reliably. |
| Roller Lever | Rolling contact reduces sliding friction; available with fixed or adjustable lever geometry. | Cam detection, conveyor equipment, sliding parts, and angular targets. | Preferable where the target approaches from the side or moves across the actuator. |
| Flexible Rod or Spring Lever | Accepts actuation from several directions and tolerates greater positional variation. | Wide-area sensing, irregular targets, and low-force mechanical detection. | Check the allowable bending direction and maximum actuator deflection. |
| Hinge Roller Lever | A roller mounted on a hinged arm offers smooth engagement over a longer travel. | Doors, cams, sliding mechanisms, and applications requiring low operating friction. | Allow sufficient clearance for the lever swing and roller path. |
| Electrical Rating | Low-Level Signal: 0.1–1 A | Designed for sensor inputs, logic-level circuits, and dry-contact signaling. | Control panels, instrumentation, counters, and low-power monitoring circuits. | Use suitable contact plating or a specified low-level switching rating for reliable small-current operation. |
| General-Purpose: 3–10 A | Common range for resistive loads at low-voltage or mains-voltage conditions. | Appliances, office equipment, small actuators, and general machine controls. | Verify the rating at the actual AC or DC voltage; AC and DC ratings are not interchangeable. |
| Higher-Current: 10–20 A | Uses larger contact systems and often requires greater terminal and enclosure capacity. | Heavier resistive loads and selected motor or solenoid control applications. | Inductive loads can produce arcing; use suppression or an intermediate relay when required. |
| Inrush or Inductive Load | Motor, lamp, capacitor, and solenoid loads may have starting currents several times higher than running current. | Motors, transformers, lamps, valves, and electromagnetic devices. | Select a dedicated load rating and consider an RC snubber, diode, varistor, or relay interface. |
| Contact Material | Silver Alloy | Good general-purpose conductivity and arc resistance for moderate-to-higher load switching. | Industrial controls, appliances, and resistive or moderately inductive loads. | May require a suitable minimum load because oxidation can affect very small currents. |
| Gold-Plated Contact | Resists oxidation and supports stable low-level signal switching. | Communication, instrumentation, control signals, and electronic inputs. | Usually not intended for high-current or high-inrush power switching unless specifically rated. |
| Silver-Nickel Alloy | Improved resistance to welding and contact wear compared with basic silver contacts. | Frequent switching and loads with moderate electrical stress. | Confirm the specified load category and switching frequency. |
| Tin-Based Contact Finish | Cost-effective finish commonly used for standard control and power contacts. | General-purpose switching where environmental and low-level requirements are moderate. | Check minimum current, humidity, corrosion, and storage requirements. |
| Housing and Insulation | Thermoplastic Housing | Lightweight electrical insulation with good dimensional stability for standard environments. | Indoor equipment, consumer products, and general industrial controls. | Check operating temperature, flammability classification, and chemical compatibility. |
| High-Temperature Engineering Polymer | Better heat resistance and dimensional stability than basic plastics. | Automotive-adjacent, appliance, lighting, and equipment exposed to elevated temperatures. | Confirm continuous and peak temperature limits rather than relying only on material name. |
| Metal-Reinforced Construction | Improves mechanical strength and mounting durability in demanding applications. | Industrial machinery, repeated actuation, vibration, and mechanically stressed assemblies. | Check insulation distances, grounding provisions, corrosion protection, and enclosure requirements. |
| Environmental Protection | Open or Vented Type | Suitable for clean, dry, protected installations; limited resistance to dust and moisture. | Enclosed control cabinets and indoor mechanisms. | Do not use where condensation, conductive dust, or splash water is expected. |
| Sealed, Approximately IP65–IP67 | Dust-tight construction with protection ranging from water jets to temporary immersion, depending on the exact rating. | Outdoor equipment, washdown areas, dusty machinery, and exposed mechanisms. | The complete installed assembly must maintain the protection level, including cable entry and mounting. |
| Corrosion-Resistant Metal Parts | Stainless or plated external components provide improved resistance to humidity and corrosive environments. | Food-processing surroundings, coastal locations, chemical exposure, and outdoor machinery. | Verify resistance to the specific chemicals, salt concentration, and cleaning agents involved. |
| Mechanical Performance | Operating Force: Approximately 0.5–3 N | Low-force actuation suitable for lightweight mechanisms and sensitive position detection. | Buttons, covers, small cams, and low-load linkages. | Confirm operating force, release force, travel, and overtravel in the actual datasheet. |
| Operating Force: Approximately 3–10 N | Higher actuation force helps resist accidental operation and vibration-related movement. | Machine guards, robust limit detection, and mechanisms with stronger return forces. | Make sure the moving equipment can supply the required force without excessive impact. |
| Mechanical Life: 100,000–1,000,000 Operations | The expected mechanical cycle life varies with actuator style, load, speed, and operating conditions. | Repeated cycling, production equipment, and automated mechanisms. | Electrical life is often lower than mechanical life, especially with inductive or high-inrush loads. |
