1, using imported normally open reed switch

2, the comparator output, the signal is clean, the waveform is good, the driving ability is strong, more than 15mA.

3, working voltage 3.3V-5V

4, output form: digital switching output (0 and 1)

5, with fixed bolt holes for easy installation

6, small pcb size: 3.2cm x 1.4cm

7, using a wide voltage LM393 comparator

Features of the reed switch:

Reed switch is short for reed. It is a passive electronic switch component with contacts. It has the advantages of simple structure, small size and easy operation. The housing is usually a sealed glass tube. There are two iron elastic reed plates, which are also filled with an inert gas called a metal crucible. In normal times, two tongues made of special materials in the glass tube are separated. When a magnetic substance is close to the glass tube, under the action of the magnetic field lines, the two reeds in the tube are magnetized to pull each other, and the tongues pulled together to connect the circuit connected to the node. After the external magnetic force disappears, the two tongues are separated by their own elasticity, and the circuit is broken. Therefore, as a line switching device controlled by a magnetic field signal, the reed switch can be used as a sensor for counting, limiting, etc. (mainly used for the production of door magnets and window magnets in security systems), and it is also widely used in various communication devices. In practice, the permanent magnets are usually used to hold the on or off of the two metal plates, so they are also called "microwave ovens".

Module instructions:

 

1. The reed switch must be used together with the magnet. When a certain magnetic force is detected, it will be in a conductive state. The module outputs a low level. When there is no magnetic force, it is in a disconnected state, and the output is on. The sensing distance with the magnet is less than 1.5 cm and is not sensitive or triggering;

 

 

3. The output of the DO module is connected to the IN end of the relay to form a high-power reed switch, which directly controls the high voltage.