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EntityQ174053· pop 63· linked from 706 articles

relay

Also known as electric relay, electrical relay, electromechanical relay

thumb|A relay thumb|Electromechanical relay principle thumb|Electromechanical relay schematic showing a control coil, four pairs of normally open and one pair of normally closed contacts thumb|An automotive-style miniature relay with the dust cover taken off

AI overview

A relay is an electrical switch that uses a small electric current to control a much larger electric current, allowing a low-power signal to turn high-power devices on or off. Relays are important because they enable safe and efficient control of powerful equipment from a distance, and they're used in everything from cars to industrial machinery.

AI-generated from the Wikipedia summary — may contain errors.

~39 min read

Encyclopedic overview

29 sections

Contents

History
Basic design and operation
Terminology
Types
Coaxial relay
Contactor
Force-guided contacts relay
Latching relay
Machine tool relay
Mercury relay
Mercury-wetted relay
Multi-voltage relays
Overload protection relay
Polarized relay
Reed relay
Safety relays
Solid-state contactor
Solid-state relay
Static relay
Time-delay relay
Vacuum relays
Applications
Protective relays
Railway signaling
Selection considerations
Safety and reliability
See also
References
External links

A relay is an electrically operated switch. It has a set of input terminals for one or more control signals, and a set of operating contact terminals. The switch may have any number of contacts in multiple contact forms, such as make contacts, break contacts, or combinations thereof.

Excerpted from Wikipedia’s “relay” article, available under the CC BY-SA 4.0 licence.