Hall effect sensors are faster than reed switches because they’re solid-state devices—no need to wait those few milliseconds for the magnetic field to overcome inertia. The downside of Hall ...

Demonstrates how to use a magnetic door/window sensor which is based on a reed switch. This app is developed for a door sensor which contains a MC-38 N.O. Normally Opened magnetic reed switch. This ...

based on magnetic field applied. Examples include, smart meters, shelf labels, reed switch replacement, smart home etc. Please refer to NMH1000 Magnetic Switch Sensor Datasheet for more information.

The extra magnets give the system better resolution at slow speeds. A Hall Effect sensor would be a more reliable way to build this to survive in the long term, but the reed switch does work.