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Aleph Reed Switches
The reed switch consists of a pair of flexible reeds made of a magnetic material, and sealed in a glass tube filled with inert gas. The reeds are overlapped but separated by a small gap. The contact area of each reed is plated with a noble metal, such as Rhodium or Ruthenium, to provide the switch with stable characteristics and long life.
Application of a magnetic field, generated by a permanent magnet or a coil, to the reed switch causes both reeds to be magnetized. This produces an N-pole at the contact area of one reed, and an S-pole at that of the other reed, in a manner shown on the drawing (left). If the magnetic attracting force overcomes the resistive force caused by elasticity of the reed, the reeds come in contact (Pull-In) i.e., the circuit is closed. Once the magnetic field is removed, the reeds are separated again by the effect of elasticity of the reed (Drop-Out) i.e., the circuit is opened.
Compact and Light
The reed switch can be mounted in a very limited space; it is ideal for use in miniatured equipment.
The switching elements of the reed switch are hermetically sealed in an inert gas atmosphere, so that they are never exposed to the external environment.
The reed switch employs no sliding parts, so there is no fatigue related to degradation in the quality of the materials used, ensuring a virtually unlimited mechanical life.
High Speed Operation
Every movable element has a very low mass resulting in a high speed of operation. This enables the reed switch to be used as an interface to a transistor or integrated circuit.
- Form "A" and "C" contacts
- Ultraminiature through large
- 3 Watt to 70 Watt loads
- Up to 15 kV breakdown voltages
Magnet Actuation Patterns
The most often used way of the actuating a reed switch is with a magnet; the typical patterns of actuation are as shown on the drawings below.
|Horizontal Actuation||Transverse Actuation|
|Perpendicular Actuation||Rotational Activation|