What is an example of a reed switch?
Reed switches actuated by magnets are commonly used in mechanical systems as proximity sensors. Examples are door and window sensors in burglar alarm systems and tamperproofing methods. Reed switches have been used in laptops to put the laptop into sleep/hibernation mode when the lid is closed.
How does a latching reed switch work?
Latching reed switches use two permanent magnets to achieve the latching function. The first magnet is partially magnetized. Bringing the contacts closer together, but they still remain open. The second magnet with an aiding field brought close to the switch will close the contacts.
What is a reed switch used for?
A reed switch is an electromagnetic switch used to control the flow of electricity in a circuit. They are made from two or more ferrous reeds encased within a small glass tube-like envelope, which become magnetised and move together or separate when a magnetic field is moved towards the switch.
How accurate is a reed switch?
Magnetic reed switch technology has been a proven technology for more than 50 years to dependably and safely sense a wide range of liquids and positioning. The internal switches are hermetically sealed and capable of switching 1/8″ accuracy and 1/32″ repeatability for standard vertical switches.
How do you activate a reed switch?
Although a reed switch can be activated by placing it inside an electrical coil, many reed switches and reed sensors are used for proximity sensing and are activated by a magnet. As the magnet is brought into the proximity of the reed sensor/switch, the device activates.
Is a reed switch normally open or closed?
Reed switches like this are called normally closed (NC) (normally switched on), so electricity flows through them most of the time.
Does reed switch have polarity?
Just as your magnet may have two poles, the reed switch’s pair of ferrous contacts are also polarized. The polarity and position of the magnet plays an important role in how your reed switch activates.
Can a reed switch become magnetized?
First, the magnet interaction effects the reed switch when a permanent magnet (as shown below) is brought into the proximity of the switch. What happens is the individual reeds become magnetized with the attractive magnetic polarity as shown.