Reed Relay 14mm

14mm Reed Relay Switch Sensor Switch

Magnetic Field Magnet Detector NO Contact Output Door Window Machine Meter Contactor

Note: It must be used for sensor purposes. It does not carry high voltage and current. At high voltage or current the product switch will be damaged.

     Reed Relay 14mm is a magnet operated normally open (NO) switch with two thin metal blades (contacts) inside a glass tube of about 2mm diameter and 14mm length. When a magnet or magnetic field comes close, the two blades pull together and the circuit closes; when the magnet moves away, the blades separate and the circuit opens. It has two leads and needs no power supply; the total length including the leads is about 44mm.

     The contacts are inside a hermetically sealed glass tube, so they are not affected by dust, moisture or dirt. Thanks to its small size it fits inside door and window frames, meter housings, floats or narrow mechanisms. Connected to a microcontroller input or an alarm circuit, it detects a door opening, a passing part or the revolutions of a rotating wheel without contact, using a magnet.

     Door and window sensors, photocopiers, dishwashers, refrigerators, gas and water meters, bicycle speedometers and float level switches are the most common areas of use.

Key features:

     Contactless switching by magnet: The contact closes when a magnet approaches and opens when it moves away. It works without touching the detected part, even through a plastic or wooden wall.

     Sealed glass tube: The contacts are inside a hermetically sealed glass tube; dust, moisture and dirt cannot reach them.

     No power needed: It is a passive two lead switch; it connects to a controller input with a pull-up resistor and draws no current itself.

     Fits narrow places: With 2mm diameter and 14mm glass length it fits inside narrow housings, meters and floats.

     Fast response: It closes in less than 1ms after the magnet approaches; suitable for pulse counting on rotating wheels and meters.

Features:

• Product type: Glass tube reed switch (reed relay), 2 leads
• Contact type: Normally open (NO), single contact
• Operation: Closes when a magnet approaches, opens when it moves away
• Recommended use: Signal and sensor circuits up to 24V
• Switching power: max 10W (voltage x current never exceeds 10W)
• Switching current: max 0.5A
• Switching voltage (catalogue value): max 200V DC / 140V AC
• Carry current: max 1A
• Contact resistance: max 150mΩ
• Insulation resistance: min 100MΩ
• Breakdown voltage: min 250V DC
• Operate sensitivity: about 10AT - 30AT
• Response (operate) time: less than 1ms (about 0.25ms - 1ms depending on source)
• Operating temperature: -40°C - 125°C
• Material: Hermetically sealed glass tube, metal leads
• Glass tube size: 2mm diameter x 14mm length
• Total length (with leads): about 44mm
• Weight: less than 1gr

Usage information:

• Connect one lead to GND and the other to a digital input of the controller with a pull-up resistor; the input goes LOW when the magnet approaches. The contact can bounce briefly when closing; if you are counting, use a short delay (debounce) in software.
• When bending the leads, hold the lead with pliers close to the glass tube and bend outside the pliers without stressing the glass body. Solder quickly; the seal at the glass end can be damaged by heat and stress.
• Bring the magnet parallel to the tube. The closing distance depends on the strength and direction of the magnet; test the distance with your magnet before mounting.

Areas of use:

•  Door and window open-closed sensors
•  Burglar alarm systems
•  Pulse counting in water and gas meters
•  Bicycle speedometers and odometers
•  Float liquid level switches
•  Lid detection in refrigerators and dishwashers
•  Cover detection in photocopiers and office machines
•  Position and limit detection (slide, lid, piston)
•  Revolution counting and speed measurement on rotating wheels

Precautions:

•  Use it for sensor purposes. Do not switch a motor, lamp, relay coil or mains load directly; run these loads through a transistor or relay board driven by the reed relay.
•  With inductive loads (coil, solenoid) an arc forms when the contact opens and the contact can weld; connect a protection diode across the load.
•  The glass tube is fragile. Do not bend the leads right at the glass body, do not squeeze the body and do not drop it; a cracked tube loses its contact seal.
•  Nearby iron parts and strong magnets can close the switch unintentionally; choose the mounting place accordingly.

Package contents:

•  1 pc Reed Relay 14mm
•  Note: The magnet is not included in the package.