Magnetic Reed Switch Sensor Module 3.3V-5V Digital Signal Output Magnetic Contact Detection Board for Arduino Raspberry Pi ESP32
SPECIFICATIONS
Brand Name: emakefun
Choice: yes
High-concerned chemical: none
Origin: Mainland China
is_customized: Yes
semi_Choice: yes

Overview
The working principle of a magnetic reed switch is very simple. Two magnetized reeds (usually composed of iron and nickel) overlapping at the endpoints are sealed in a glass tube. The two reeds overlap with a small gap (only about a few microns) between them. The contacts on these two reeds are coated with very hard metals, usually rhodium and ruthenium, which greatly improve the switching frequency and product life. The glass tube is filled with high-purity inert gas (such as nitrogen), and some dry spring switches are made into a vacuum state inside to improve their high-pressure performance. The function of a reed is equivalent to that of a magnetic flux conductor. Before operation, the two spring leaves did not come into contact; When a magnetic field is generated by a permanent magnet or electromagnetic coil, the applied magnetic field causes different polarities near the endpoints of the two spring plates. When the magnetic force exceeds the elastic force of the spring plates themselves, these two spring plates will attract and conduct the circuit; When the magnetic field weakens or disappears, the dry spring is released due to its own elasticity, and the contact surface will separate to open the circuit. The reed switch is normally open in the absence of a magnetic field, and when a sufficiently strong magnetic field is generated, the two reeds will be attracted together.
Schematic diagram

Module parameters
Pin name |
description |
G |
GND |
V |
VCC |
S |
When there is a magnet on the sensor, output a low level; when there is no magnet on the sensor, output a high level |
Supply voltage: 3V3/5V
Connection method: 3PIN anti reverse DuPont wire
Module size: 38.4x 22.4 mm
Installation method: M4 screws compatible with Lego socket for fixation










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