Engineering:Key switch
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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
- ↑ Martston, R. M. (1998-07-15) (in en). Security Electronics Circuits Manual. Newnes. ISBN 978-0-08-093854-7. https://books.google.com/books?id=N1brCyiY1OgC&dq=key+operated+switch+types+of+switches&pg=PA10.
- ↑ Safety), Center for Chemical Process (2017-01-06) (in en). Guidelines for Safe Automation of Chemical Processes. John Wiley & Sons. ISBN 978-1-119-35189-4. https://books.google.com/books?id=VpXbDQAAQBAJ&dq=key+switch+security+access+restricted&pg=PA119.
- ↑ Schum, John L. (1988) (in en). Electronic Locking Devices. Butterworths. ISBN 978-0-409-90125-2. https://books.google.com/books?id=0DBSAAAAMAAJ&q=key+switch+access+restricted.
- ↑ "Key switches". Maplin Electronics. http://www.maplin.co.uk/c/components/switches/key-switches. Retrieved 23 August 2014.
- ↑ "Simulation of a Peacekeeper missile launch". Defence Imagery. http://dodimagery.afis.osd.mil/imagery.html#a=search&s=simulation%20of%20a%20Peacekeeper%20Missile%20Launch&t=0&guid=0f307fd0b6d2c847b0c0e2dcbaac7a20a6f6a092. Retrieved 23 August 2014.
- ↑ "Low-Cost Security Measures for School Facilities". National Clearinghouse for Educational Facilities. http://www.ncef.org/pubs/low_cost_measures.pdf. Retrieved 1 September 2014.
- ↑ "Product Bulletin for 30 Amp AC Toggle Switches". Leviton. http://www.leviton.com/OA_HTML/ibcGetAttachment.jsp?cItemId=xreQ9kM.SwSAGa6JaqTCzw. Retrieved 1 September 2014.
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