Key switch

Last updated
Key switch
Key switch.jpg
On/off key switch
Working principle Switch
Electronic symbol
IEEE 315 Contacts, Switches, Contactors, and Relays Symbols (78).svg

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]

Related Research Articles

<span class="mw-page-title-main">GSM</span> Cellular telephone network standard

The Global System for Mobile Communications (GSM) is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe the protocols for second-generation (2G) digital cellular networks used by mobile devices such as mobile phones and tablets. GSM is also a trade mark owned by the GSM Association. GSM may also refer to the Full Rate voice codec.

<span class="mw-page-title-main">Tomahawk (missile)</span> Long-range, subsonic cruise missile

The TomahawkLand Attack Missile (TLAM) is a long-range, all-weather, jet-powered, subsonic cruise missile that is primarily used by the United States Navy and Royal Navy in ship and submarine-based land-attack operations.

<span class="mw-page-title-main">Moore's law</span> Observation on the growth of integrated circuit capacity

Moore's law is the observation that the number of transistors in an integrated circuit (IC) doubles about every two years. Moore's law is an observation and projection of a historical trend. Rather than a law of physics, it is an empirical relationship linked to gains from experience in production.

<span class="mw-page-title-main">Access control</span> Selective restriction of access to a place or other resource, allowing only authorized users

In physical security and information security, access control (AC) is the selective restriction of access to a place or other resource, while access management describes the process. The act of accessing may mean consuming, entering, or using. Permission to access a resource is called authorization.

<span class="mw-page-title-main">Permissive action link</span> Access control device for nuclear weapons

A permissive action link (PAL) is an access control security device for nuclear weapons. Its purpose is to prevent unauthorized arming or detonation of a nuclear weapon. The United States Department of Defense definition is:

A device included in or attached to a nuclear weapon system to preclude arming and/or launching until the insertion of a prescribed discrete code or combination. It may include equipment and cabling external to the weapon or weapon system to activate components within the weapon or weapon system.

<span class="mw-page-title-main">North Korea and weapons of mass destruction</span>

North Korea has a military nuclear weapons program and, as of early 2020, is estimated to have an arsenal of approximately 30 to 40 nuclear weapons and sufficient production of fissile material for six to seven nuclear weapons per year. North Korea has also stockpiled a significant quantity of chemical and biological weapons. In 2003, North Korea withdrew from the Treaty on the Non-Proliferation of Nuclear Weapons (NPT). Since 2006, the country has conducted six nuclear tests at increasing levels of expertise, prompting the imposition of sanctions.

<span class="mw-page-title-main">Amstrad PCW</span>

The Amstrad PCW series is a range of personal computers produced by British company Amstrad from 1985 to 1998, and also sold under licence in Europe as the "Joyce" by the German electronics company Schneider in the early years of the series' life. The PCW, short for Personal Computer Word-processor, was targeted at the word processing and home office markets. When it was launched the cost of a PCW system was under 25% of the cost of almost all IBM-compatible PC systems in the UK, and as a result the machine was very popular both in the UK and in Europe, persuading many technophobes to venture into using computers. The series is reported to have sold 1.5 million units. However the last two models, introduced in the mid-1990s, were commercial failures, being squeezed out of the market by the falling prices, greater capabilities and wider range of software for IBM-compatible PCs.

<span class="mw-page-title-main">FGM-148 Javelin</span> American-made portable fire-and-forget anti-tank missile

The FGM-148 Javelin, or Advanced Anti-Tank Weapon System-Medium (AAWS-M), is an American-made man-portable anti-tank system in service since 1996, and continuously upgraded. It replaced the M47 Dragon anti-tank missile in US service. Its fire-and-forget design features automatic infrared guidance, allowing the user to seek cover immediately after launch, in contrast to wire-guided systems, like the system used by the Dragon, which require a user to guide the weapon throughout the engagement. The Javelin's high-explosive anti-tank (HEAT) warhead can defeat modern tanks by top-down attack, hitting them from above, where their armor is thinnest, and is also useful against fortifications in a direct attack flight.

<span class="mw-page-title-main">Nike Hercules</span> Type of surface-to-air missile

The Nike Hercules, initially designated SAM-A-25 and later MIM-14, was a surface-to-air missile (SAM) used by U.S. and NATO armed forces for medium- and high-altitude long-range air defense. It was normally armed with the W31 nuclear warhead, but could also be fitted with a conventional warhead for export use. Its warhead also allowed it to be used in a secondary surface-to-surface role, and the system also demonstrated its ability to hit other short-range missiles in flight.

<span class="mw-page-title-main">Lock and key</span> Mechanical or electronic fastening device

A lock is a mechanical or electronic fastening device that is released by a physical object, by supplying secret information, by a combination thereof, or it may only be able to be opened from one side, such as a door chain.

<span class="mw-page-title-main">India and weapons of mass destruction</span>

India possesses nuclear weapons and previously developed chemical weapons. Although India has not released any official statements about the size of its nuclear arsenal, recent estimates suggest that India has 164 nuclear weapons and has produced enough weapons-grade plutonium for up to 200 nuclear weapons. In 1999, India was estimated to have 800 kilograms (1,800 lb) of separated reactor-grade plutonium, with a total amount of 8,300 kilograms (18,300 lb) of civilian plutonium, enough for approximately 1,000 nuclear weapons. India has conducted nuclear weapons tests in a pair of series namely Pokhran I and Pokhran II.

<span class="mw-page-title-main">South Africa and weapons of mass destruction</span>

From the 1960s to the 1990s, South Africa pursued research into weapons of mass destruction, including nuclear, biological, and chemical weapons under the apartheid government. South Africa’s nuclear weapons doctrine was designed for political leverage rather than actual battlefield use, specifically to induce the United States of America to intervene in any regional conflicts between South Africa and the Soviet Union or its proxies. To achieve a minimum credible deterrence, a total of six nuclear weapons were covertly assembled by the late 1980s.

<span class="mw-page-title-main">Two-person rule</span> Action only authorized by two or more people

The two-person rule is a control mechanism designed to achieve a high level of security for especially critical material or operations. Under this rule, access and actions require the presence of two or more authorized people at all times.

<span class="mw-page-title-main">Winlogon</span> Component of Microsoft Windows operating systems

Winlogon is the component of Microsoft Windows operating systems that is responsible for handling the secure attention sequence, loading the user profile on logon, creates the desktops for the window station, and optionally locking the computer when a screensaver is running. In Windows Vista and later operating systems, the roles and responsibilities of Winlogon have changed significantly.

<span class="mw-page-title-main">Computer keyboard</span> Data input device

A computer keyboard is a peripheral input device modeled after the typewriter keyboard which uses an arrangement of buttons or keys to act as mechanical levers or electronic switches. Replacing early punched cards and paper tape technology, interaction via teleprinter-style keyboards have been the main input method for computers since the 1970s, supplemented by the computer mouse since the 1980s.

<span class="mw-page-title-main">AIM-9 Sidewinder</span> Short-range air-to-air missile

The AIM-9 Sidewinder is a short-range air-to-air missile. Entering service with the United States Navy in 1956 and the Air Force in 1964, the AIM-9 is one of the oldest, cheapest, and most successful air-to-air missiles. Its latest variants remain standard equipment in most Western-aligned air forces. The Soviet K-13, a reverse-engineered copy of the AIM-9B, was also widely adopted.

<span class="mw-page-title-main">Francis E. Warren Air Force Base</span> US Air Force base near Cheyenne, Wyoming, United States

Francis E. Warren Air Force Base, shortened as F.E. Warren AFB is a United States Air Force base (AFB) located approximately 3 miles (4.8 km) west of Cheyenne, Wyoming. It is one of three strategic-missile bases in the U.S. It was named in honor of Francis E. Warren in 1930. Warren AFB is home of the 90th Missile Wing, assigned to the Twentieth Air Force, Air Force Global Strike Command. The 90 MW operates the LGM-30G Minuteman III ICBM. It is also the home of Twentieth Air Force, which commands all U.S. Air Force ICBMs.

Mohamed M. Atalla was an Egyptian-American engineer, physicist, cryptographer, inventor and entrepreneur. He was a semiconductor pioneer who made important contributions to modern electronics. He is best known for inventing the MOSFET in 1959, which along with Atalla's earlier surface passivation processes, had a significant impact on the development of the electronics industry. He is also known as the founder of the data security company Atalla Corporation, founded in 1972. He received the Stuart Ballantine Medal and was inducted into the National Inventors Hall of Fame for his important contributions to semiconductor technology as well as data security.

<span class="mw-page-title-main">RTX Corporation</span> American multinational aerospace and defense conglomerate

RTX Corporation, formerly Raytheon Technologies Corporation, is an American multinational aerospace and defense conglomerate headquartered in Arlington, Virginia. It is one of the largest aerospace and defense manufacturers in the world by revenue and market capitalization, as well as one of the largest providers of intelligence services. RTX manufactures aircraft engines, avionics, aerostructures, cybersecurity solutions, guided missiles, air defense systems, satellites, and drones. The company is also a large military contractor, getting a significant portion of its revenue from the U.S. government.

References

  1. Martston, R. M. (1998-07-15). Security Electronics Circuits Manual. Newnes. ISBN   978-0-08-093854-7.
  2. Safety), Center for Chemical Process (2017-01-06). Guidelines for Safe Automation of Chemical Processes. John Wiley & Sons. ISBN   978-1-119-35189-4.
  3. Schum, John L. (1988). Electronic Locking Devices. Butterworths. ISBN   978-0-409-90125-2.
  4. "Key switches". Maplin Electronics . Retrieved 23 August 2014.
  5. "Simulation of a Peacekeeper missile launch". Defence Imagery. Retrieved 23 August 2014.
  6. "Low-Cost Security Measures for School Facilities" (PDF). National Clearinghouse for Educational Facilities. Retrieved 1 September 2014.
  7. "Product Bulletin for 30 Amp AC Toggle Switches". Leviton. Retrieved 1 September 2014.