Editing Reed switch (section)

===Reed relays===
{{Main|Reed relay}}
One or more reed switches inside an electromagnetic coil constitute a reed relay. Reed relays are used when operating currents are relatively low, and offer high operating speed, good performance with very small currents that are not reliably switched by conventional contacts, high reliability and long life.  Millions of reed relays were used in [[telephone exchange]]s in the 1970s and 1980s. In particular, they were used for switching in the British [[TXE]] family of telephone exchanges. The inert atmosphere around the reed contacts ensures that oxidation will not affect the contact resistance.  Mercury-wetted reed relays are sometimes used, especially in high-speed counting circuits.