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What does a reed switch sense?
Reed switches are used as proximity sensors to control robotic motion, conveyor speed, location and angle. They can sense whether valves, tracks, hoppers, and doors are open or closed, or if containers or conveyors are full or empty. Reed sensors report the postion and movement of products in vending machines.
Are reed switches sensors?
Magnetic sensors 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.
What should I know about using reed switches?
Reed switches are most susceptible to shock and vibration along the axis on which the switching components move. If excessive mechanical shock is expected to occur regularly when the switch is put into use, care should be taken to choose an appropriately sized reed switch that can best hold up to expected impact.
Why are the contacts on a reed switch polarized?
Normally Closed reed switches operate on the same principle, except that the switch uses a built-in magnet to keep its two contacts in a polarized state. This means that the switch’s default position is to keep the circuit closed, allowing the electrical current to flow continuously.
How does a reed switch hook up to a SparkFun?
Reed switches are magnetically-actuated electrical switches (not magically-actuated, though it seems that way sometimes). When the body of the switch is exposed to a magnetic field — like a magnet or even a strong electrical current — two ferrous materials inside pull together, the connection closes, and current can flow.
What happens when the magnet is removed from a reed switch?
When the outside magnet is removed, the stiff contacts spring back into their original position, thus breaking the circuit and halting the electrical current. Normally Closed reed switches operate on the same principle, except that the switch uses a built-in magnet to keep its two contacts in a polarized state.