Reed switch is a kind of passive electronic switching component with contacts with a simple structure, small size and easy to use. It consists of a sealed glass envelope where there are two ferrous elastic reeds and is filled with inert gas called rhodium.
Now, this reed switch is pre-soldered on a PCB board that comes with basic electronic components to help beginner.
Comes with Power indicator LED and status indicator LED, there is also a comparator and potentiometer to adjust the threshold, although it is not really neccesary for Reed switch. Check out the explaination from Robojax:
Reed switch is a kind of passive electronic switching component with contacts with a simple structure, small size and easy to control. It consists of a sealed glass envelope where there are two ferrous elastic reeds and is filled with inert gas called rhodium. Normally, the two reeds are separated in the envelope. When a magnetic substance approaches to the glass envelope, the reeds will come together due to the magnetic field thus completing an electric circuit. When the external magnetic field disappears, two reeds will be separated because of their elasticity, the circuit is also disconnected. Therefore, as a circuit switching device controlled by magnetic field signals, reed switch can also be used as a sensor for counting and limiting, etc. ( applied in the security systems, mainly used for production of door and window magnets), and it is also widely used in a variety of communications devices. In practice, it is common to use the two permanent magnets to control connection of two metal sheets, thus it is also called a "magnetron".
- Imported normally-open reed
- Comparator output, clear signal, nice waveform and driving ability, more than 15mA.
- Working voltage: 3.3V-5V
- Output format: Digital switching output ( 0 and 1 )
- With fix bolt holes for easy installation
- Small PCB size: 32mm x 14mm
- Adopting LM393 comparator with wide voltage
- Might need to get the magnet to activate the switch
Instructions for module:
- The reed switch must work together with the magnet, when it detects magnetism, the circuit is connected and the module outputs low level; when there is no magnetic force, it is disconnected and module outputs high level. If the sensing range of the reed to the magnet is more than 1.5cm, it will become insensitive and it may not be triggered;
- DO output terminal on the module can be directly connected to I / O port of MCU, the trigger state of reed switch can be detected through MCU;
- DO output terminal on the module can be connected to IN terminal on relay to form a high-power reed switch for direct control of high voltage.
It has been applied in stored program control exchanges, photocopiers, washing machines, refrigerators, cameras, Disinfection cabinets, door magnets, window magnets, electromagnetic relays, electronic weighing devices, level meters, gas meters, water meters, etc..
- 1 x Reed switch module
Documents or Tutorials:
- Wiring Reed Switch Module with Arduino Microcontroller, tutorial by 14core.
- How to activate LED with Magnetic, by Eric20156065 in instructables
- Arduino-Magnetic Reed Switch, by Danny van den Brande in Hackster.io