reed relay

electronics

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Last updated

July 13, 2026

Quick Summary

A reed relay is an electrical switch operated by a magnetic field. It consists of two flat metal reeds, typically made of a nickel-iron alloy, enclosed in a glass capsule. When a magnetic field is applied along the length of the reeds, they become magnetized with opposite poles at their overlapping ends, causing them to attract each other and make electrical contact. When the magnetic field is removed, the reeds spring back to their open position. Reed relays are known for their reliability and long operational life, making them suitable for applications like telephone equipment.12

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Relays.
Present reed switches used in telephone equipment are operated by up to 50 volts direct current. Typically, the reed closes at 58 ampere-turns and releases at 15 ampere-turns, the hold current being 27 ampere-turns. The contact closes to give a stable contact resistance in 2 milliseconds,…
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Present reed switches used in telephone equipment are operated by up to 50 volts direct current. Typically, the reed closes at 58 ampere-turns and releases at 15 ampere-turns, the hold current being 27 ampere-turns. The contact closes to give a stable contact resistance in 2 milliseconds,…
Read More