Reed switch circuit

In this article, we will go over how to place a reed switch in a circuit so that a magnet can be used to close the circuit. This is a simple reed switch (Magnetic Switch) circuit to turn on and off a white LED. A reed switch closes the. First bend both legs of the switch to point perpendicularly away from the body of the switch, so they form a “U” shape.

The body of the glass-tubed reed switch is very delicate. Photo: A typical reed switch (a Comus RI-23).

You can just see the two overlapping metal contacts (reeds) inside the glass envelope. The spring force of the reeds causes them to separate, and open the circuit , when the magnetic field ceases. Another configuration contains a non-ferromagnetic normally-closed contact that opens when the ferromagnetic normally-open contact closes. A thin layer of non-ferromagnetic material is applied to the reed switch.

Reed Switches can switch on low power devices directly, such as LEDs, buzzers. But for sensing it should be used as part of a potential-divider. Supply voltage up to 18v.

You might be able to use a thyristor for this.

Once triggered they stay on until the current is interrupted by another switch. Alternatively, you can make a thyristor with a PNP and NPN transistor. A web search should get . It is assumed that the ideal reed switch load is a Resistive Loa but it is almost impossible to reduce any load to purely resistive.

Reed switches have three basic configurations: Normally. Open ( NO), Normally Closed (NC) and Form C which has both NO and NC. Depending on this original contact configuration, the contacts will either complete or interrupt a circuit when actuated by a magnetic field. The reed blades act as magnetic flux. Construction and Working.

We will need: - Arduino Uno. Once procured components assemble the circuit : . CircuitLab provides online, in-browser tools for schematic capture and circuit simulation. These tools allow students, hobbyists, and professional engineers to design and analyze analog and digital systems before ever building a prototype.

Online schematic capture lets hobbyists easily share and discuss . It depends on your usage. You can of course logically invert the action of the reed switch in the circuitry that you connect it to but there is a good chance that this misses the point of using a reed switch in the first place. They draw zero current when open, and they can operate for at least hundreds of thousands, if not millions, of cycles.

They are ideal for low current applications where the circuit merely checks for a reed switch contact . If the magnetic attracting force overcomes the resistive force caused by elasticity of the ree the reeds come in contact (Pull-In) i. Learn more about magnetic reed switch technology with these application notes and technical diagrams from SMD Fluid Controls. The contact material, the size of the switch and the mechanical form may also be developed with some particular application in mind. I was thinking something simillar to the battery level measuring circuit where the GND is conncted instead to a .