magnetic reed switch is an electrical switch operated by an applied magnetic field. It consists of a pair of contacts on ferromagnetic metal reeds in a hermetically sealed glass envelope. The contacts may be normally open, closing when a magnetic field is present, or normally closed and opening when a magnetic field is applied. The switch may be actuated by a coil, making a reed relay,or by bringing a magnet near to the switch. Once the magnet is pulled away from the switch, the reed switch will go back to its original position.
An example of a reed switch’s application is to detect the opening of a door, when used as a proximity switch for a burglar alarm.
- Ability to switch up to 10,000 Volts
- Ability to switch currents up to 5 Amps
- Ability to switch or carry as low as 10 nanoVolts without signal loss
- Ability to switch or carry as low as 1 femtoAmp without signal loss
- Ability to switch or carry up to 7 GigaHz with minimal signal loss
- Isolation across the contacts up to 1015 Ω
- Contact resistance (on resistance) typical 50 milliOhms (mΩ).
- In its off state it requires no power or circuitry
- Ability to offer a latching feature
- Operate time in the 100 µs to 300 µs range
- Ability to operate over extreme temperature ranges from –55 °C to 200 °C
- Ability to operate in all types of environments including air, water, vacuum, oil, fuels, and dust laden atmospheres
- Ability to withstand shocks up to 200 Gs
- Ability to withstand vibration environments of 50 Hz to 2000 Hz at up to 30 Gs
- Long life. With no wearing parts, load switching under 5 Volts at 10 mA, will operate well into the billions of operation.