3-Pin Magnetic Reed Switch (SPDT NO/NC) - 60V 4W Sensor | MKA-27
3-Pin Magnetic Reed Switch (SPDT NO/NC) - 60V 4W Sensor | MKA-27
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Short Product Description
Short Product Description
Upgrade your automation and security projects with our highly responsive 3-Pin Magnetic Reed Switch. Featuring both Normally Open (NO) and Normally Closed (NC) capabilities within a compact 2.5x14mm glass enclosure, this SPDT sensor delivers reliable switching up to 60V. Perfect for STEM electronics, DIY circuitry, and industrial proximity sensing.
Key Features
Key Features
- Dual-State Operation (SPDT): Features both NO and NC pins, allowing for versatile circuit design in a single component.
- Hermetically Sealed Glass Tube: Internal rhodium contacts are protected within an inert gas environment, preventing oxidation and ensuring long-term reliability.
- Lightning-Fast Response: Actuates in just 0.25ms with a bounce time of 0.05ms, ideal for high-speed counting and frequency applications (up to 3000Hz).
- Compact Footprint: At just 2.5 x 14mm, it easily integrates into tight enclosures, PCB layouts, and small-scale STEM projects.
- No Power Consumption: As a passive component driven entirely by magnetic fields, it requires zero standby power, maximizing battery life in portable setups.
Full Product Description
Full Product Description
Versatile Magnetic Control for Advanced Projects
Whether you are building a custom home security system or prototyping an automated robotics project, reliable sensor feedback is critical. The 3-Pin Magnetic Reed Switch (MKA-27) offers exceptional versatility by combining both Normally Open (NO) and Normally Closed (NC) functions into a single, compact component. This Single Pole Double Throw (SPDT) configuration allows you to easily toggle circuits without needing multiple sensors.
How the 3-Pin Reed Switch Works
Unlike standard 2-pin models, this 3-pin switch provides a seamless state conversion. The hermetically sealed glass tube contains rhodium-plated elastic reeds surrounded by an inert gas.
- Without a Magnetic Field: The common pin connects to the Normally Closed (NC) pin.
- With a Magnetic Field: When a permanent magnet approaches, the magnetic flux magnetizes the reeds, pulling the common pin to the Normally Open (NO) contact and completing your secondary circuit.
Once the magnetic field is removed, the natural elasticity of the metal snaps the connection back to its original state in mere milliseconds.
Engineered for Precision and Longevity
Designed for high-frequency operations, this switch boasts a rapid response time of 0.25ms and a lifespan of up to $5 \times 10^6$ cycles under standard load. Please note that while the internal components are sealed, the external metal pins do not possess waterproofing features. Ensure your application environment remains dry to prevent short circuits and maintain optimal performance.
Technical Specifications
Technical Specifications
- Model: ModelMKA‑27 (3‑Pin SPDT)
- Package type: Glass‑tube reed switch
- Dimensions (glass tube): 2.5 mm diameter × 14 mm length
- Maximum power rating: 4 W
- Maximum switching voltage: 60 V DC / 60 V AC
- Maximum switching current: 0.25 A
- Maximum load current: 0.5 A
- Maximum contact resistance: 115 mΩ
- Insulation resistance: typically 2×1072×107 to 2×1092×109 Ω
- Action (operate) time: 0.25 ms
- Bounce time: 0.05 ms
- Maximum response frequency: 3000 Hz
- Sensitivity range: 10–40 AT (ampere‑turns)
- Electrical life (under light load): 5×1065×106 cycles at 50 mV, 10 mA
Delivery Options
Delivery Options
- Local delivery within Hong Kong and in-store pickup.
- Free shipping for orders of HK$400 or above; HK$35 shipping fee for orders below HK$400.
- Shipped by SF Express, usually dispatched the same day for orders confirmed before 6:00 PM (Mon–Sat).
- Estimated delivery time: 1–3 business days after dispatch (Hong Kong).
- In-store pickup details (location and time) will be confirmed by email or phone message.
- Delivery times are estimates and may be affected by weather or unforeseen circumstances.
FAQ Section
FAQ Section
Q. What is the difference between a 2-pin and 3-pin reed switch?
A. A standard 2-pin switch is typically just Normally Open (it closes when a magnet is near). A 3-pin switch is an SPDT (Single Pole Double Throw) switch, meaning it has both a Normally Open (NO) and a Normally Closed (NC) contact. This allows you to actively switch power between two different circuits using a single magnet.
Q. Can I use this with microcontrollers like Arduino or Raspberry Pi?
A. Yes, absolutely. Because it acts as a simple mechanical switch, it can easily be wired to the digital input pins of an Arduino or Raspberry Pi to detect doors opening, motor rotations, or object proximity.
Q. Is this magnetic sensor waterproof?
A. No. While the glass tube provides a tight seal for the internal contacts, the exposed metal pins are not waterproof. If you plan to use this in a wet environment, you must manually encapsulate the switch and soldered connections in waterproof potting compound or heat shrink tubing.
Target Users / Applications
Target Users / Applications
- STEM Students & Educators: Ideal for teaching magnetic fields and basic logic circuits.
- DIY Electronics Enthusiasts: Perfect for Arduino/Raspberry Pi projects, smart home triggers, and custom alarms.
- Industrial Engineers: Used in fluid level sensors, proximity switches, and mechanical counters.
