How does a basic magnetic reed switch open and close a circuit?
1 Answer
A basic magnetic reed switch is a simple electromagnetic device used to control electrical circuits. It consists of two metal reeds encased within a sealed glass tube that is filled with an inert gas. One of the reeds is a ferromagnetic material (usually iron or steel), while the other is non-magnetic (usually nickel or copper).
When no external magnetic field is present, the two reeds remain in their natural, unattracted state and are positioned close to each other inside the glass tube. In this configuration, the ferromagnetic reed makes contact with the non-magnetic reed, completing an electrical circuit. This closed circuit allows current to flow through the switch and any connected components.
However, when an external magnetic field is applied near the reed switch (such as bringing a magnet close to it), the ferromagnetic reed becomes magnetized and is attracted to the magnetic field. As a result, it bends and moves away from the non-magnetic reed, breaking the contact between them. This open position interrupts the electrical circuit, and current can no longer flow through the switch.
In summary, a basic magnetic reed switch opens and closes a circuit through the manipulation of an external magnetic field. The switch is normally closed (current flows) when no external magnetic field is present, and it opens (interrupts current flow) when an external magnetic field is applied. These switches are often used in various applications such as door and window sensors, security systems, and proximity detectors.
When no external magnetic field is present, the two reeds remain in their natural, unattracted state and are positioned close to each other inside the glass tube. In this configuration, the ferromagnetic reed makes contact with the non-magnetic reed, completing an electrical circuit. This closed circuit allows current to flow through the switch and any connected components.
However, when an external magnetic field is applied near the reed switch (such as bringing a magnet close to it), the ferromagnetic reed becomes magnetized and is attracted to the magnetic field. As a result, it bends and moves away from the non-magnetic reed, breaking the contact between them. This open position interrupts the electrical circuit, and current can no longer flow through the switch.
In summary, a basic magnetic reed switch opens and closes a circuit through the manipulation of an external magnetic field. The switch is normally closed (current flows) when no external magnetic field is present, and it opens (interrupts current flow) when an external magnetic field is applied. These switches are often used in various applications such as door and window sensors, security systems, and proximity detectors.