A key switch (sometimes called a keyswitch or lock switch) is a key-operated switch.[1] Key switches are used in situations where access to the switch's functions needs to be restricted.[2][3]
Key switches are available as components with solder connections, and are available with a variety of ampere ratings. They may use tubular or other specially-shaped keys for extra security.[4]
Key switches have been used for a variety of purposes, up to and including the launch of nuclear missiles.[5]
In less secure applications such as corridor and restroom lighting controls in public buildings, tamper-resistant switches with a simpler key mechanism may be used instead.[6][7]
References
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