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Index Relay

A relay is an electrically operated switch. [1]

115 relations: A Symbolic Analysis of Relay and Switching Circuits, Acceleration, Actuator, Aerospace, Alternating current, Analogue switch, Armature (electrical engineering), ARRA (computer), Avionics, Bimetallic strip, Boolean algebra, Buchholz relay, Carbon monoxide, Carl Friedrich Gauss, Characteristic impedance, Circuit breaker, Claude Shannon, Coalescence (physics), Contact protection, Contactor, Corrosion, Crossbar switch, Dashpot, Delay line memory, Design, Digital protective relay, DIN 72552, Diode, Direct current, Double switching, Dry contact, Duty cycle, Earth leakage circuit breaker, Edward Davy, Electric arc, Electric current, Electric motor, Electrical contacts, Electrical equipment in hazardous areas, Electrical reactance, Electrical telegraph, Electricity, Electromagnet, Electromechanics, Fleetwood, Flip-flop (electronics), Flyback diode, G-force, H bridge, Harvard Mark II, ..., Headlamp, Hysteresis, Inductance, Inert gas, Inrush current, John Wiley & Sons, Joseph Henry, Ladder logic, Light-emitting diode, Magnet, Magnetic core, Magnetic field, Magnetic reluctance, Mercury (element), Mercury relay, Microprocessor, Moving parts, Nanoelectromechanical relay, Number One Electronic Switching System, Opto-isolator, Overcurrent, Ozone, Photodiode, Printed circuit board, Programmable logic controller, Protective relay, Race condition, Railway signalling, Reed relay, Reed switch, Relay, Relay logic, Remanence, Resistance thermometer, Samuel Morse, Semiconductor, Sequential logic, Shock (mechanics), Silver, Silver oxide, Snubber, Solid-state electronics, Solid-state relay, Spring (device), Stepping switch, Strowger switch, Switch, Telegraphy, Telephone exchange, Thermocouple, Thyristor, Transceiver, Transistor, Transistor–transistor logic, Transmission line, TRIAC, United Kingdom, United States Department of the Army, Vacuum, Voltage spike, Wilhelm Eduard Weber, Wire spring relay, Yoke, Z2 (computer), Z3 (computer). Expand index (65 more) »

A Symbolic Analysis of Relay and Switching Circuits

A Symbolic Analysis of Relay and Switching Circuits is the title of a master's thesis written by computer science pioneer Claude E. Shannon while attending the Massachusetts Institute of Technology (MIT) in 1937.

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In physics, acceleration is the rate of change of velocity of an object with respect to time.

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An actuator is a component of a machine that is responsible for moving and controlling a mechanism or system, for example by opening a valve.

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Aerospace is the human effort in science, engineering and business to fly in the atmosphere of Earth (aeronautics) and surrounding space (astronautics).

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Alternating current

Alternating current (AC) is an electric current which periodically reverses direction, in contrast to direct current (DC) which flows only in one direction.

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Analogue switch

The analogue (or analog) switch, also called the bilateral switch, is an electronic component that behaves in a similar way to a relay, but has no moving parts.

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Armature (electrical engineering)

In electrical engineering, an armature is the power-producing component of an electric machine.

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ARRA (computer)

The ARRA (for "Automatische Relais Rekenmachine Amsterdam", Automatic Relay Calculator Amsterdam) was the first Dutch computer, and was built from relays for the Dutch Mathematical Centre (Dutch: Mathematisch Centrum), which later became the Centrum Wiskunde & Informatica (CWI).

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Avionics are the electronic systems used on aircraft, artificial satellites, and spacecraft.

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Bimetallic strip

A bimetallic strip is used to convert a temperature change into mechanical displacement.

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Boolean algebra

In mathematics and mathematical logic, Boolean algebra is the branch of algebra in which the values of the variables are the truth values true and false, usually denoted 1 and 0 respectively.

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Buchholz relay

In the field of electric power distribution and transmission, a Buchholz relay is a safety device mounted on some oil-filled power transformers and reactors, equipped with an external overhead oil reservoir called a "conservator".

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Carbon monoxide

Carbon monoxide (CO) is a colorless, odorless, and tasteless gas that is slightly less dense than air.

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Carl Friedrich Gauss

Johann Carl Friedrich Gauss (Gauß; Carolus Fridericus Gauss; 30 April 177723 February 1855) was a German mathematician and physicist who made significant contributions to many fields, including algebra, analysis, astronomy, differential geometry, electrostatics, geodesy, geophysics, magnetic fields, matrix theory, mechanics, number theory, optics and statistics.

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Characteristic impedance

The characteristic impedance or surge impedance (usually written Z0) of a uniform transmission line is the ratio of the amplitudes of voltage and current of a single wave propagating along the line; that is, a wave travelling in one direction in the absence of reflections in the other direction.

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Circuit breaker

A circuit breaker is an automatically operated electrical switch designed to protect an electrical circuit from damage caused by excess current from an overload or short circuit.

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Claude Shannon

Claude Elwood Shannon (April 30, 1916 – February 24, 2001) was an American mathematician, electrical engineer, and cryptographer known as "the father of information theory".

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Coalescence (physics)

Coalescence is the process by which two or more droplets, bubbles or particles merge during contact to form a single daughter droplet, bubble or particle.

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Contact protection

Contact protection methods are designed to limit the wear and degradation that occur during the normal use of contacts within an electromechanical switch, relay or contactor.

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A contactor is an electrically-controlled switch (relay) used for switching an electrical power circuit.

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Corrosion is a natural process, which converts a refined metal to a more chemically-stable form, such as its oxide, hydroxide, or sulfide.

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Crossbar switch

In electronics, a crossbar switch (cross-point switch, matrix switch) is a collection of switches arranged in a matrix configuration.

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A dashpot is a mechanical device, a damper which resists motion via viscous friction.

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Delay line memory

Delay line memory is a form of computer memory, now obsolete, that was used on some of the earliest digital computers.

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Design is the creation of a plan or convention for the construction of an object, system or measurable human interaction (as in architectural blueprints, engineering drawings, business processes, circuit diagrams, and sewing patterns).

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Digital protective relay

In utility and industrial electric power transmission and distribution systems, a digital protective relay is a computer-based system with software-based protection algorithms for the detection of electrical faults.

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DIN 72552

DIN 72552 is a DIN standard for automobile electric terminal numbers, standardizing almost every contact in an automobile with a number code.

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A diode is a two-terminal electronic component that conducts current primarily in one direction (asymmetric conductance); it has low (ideally zero) resistance in one direction, and high (ideally infinite) resistance in the other.

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Direct current

Direct current (DC) is the unidirectional flow of electric charge.

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Double switching

A single-switched relay can close inadvertently in response to a single false feed current. A double-switched relay cannot close inadvertently with the application of the same current. At least two separate faults would be required to allow this relay to close inadvertently. Double switching, double cutting, or double breaking is the practice of using a multipole switch to close or open both the positive and negative sides of a DC electrical circuit, or both the hot and neutral sides of an AC circuit.

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Dry contact

Dry contact may mean any of the following in electronics.

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Duty cycle

A duty cycle is the fraction of one period in which a signal or system is active.

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Earth leakage circuit breaker

An Earth-leakage circuit breaker (ELCB) is a safety device used in electrical installations with high Earth impedance to prevent shock.

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Edward Davy

Edward Davy (16 June 1806 – 26 January 1885) was an English physician, scientist, and inventor who played a prominent role in the development of telegraphy, and invented an electric relay.

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Electric arc

An electric arc, or arc discharge, is an electrical breakdown of a gas that produces an ongoing electrical discharge.

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Electric current

An electric current is a flow of electric charge.

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Electric motor

An electric motor is an electrical machine that converts electrical energy into mechanical energy.

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Electrical contacts

An electrical contact is an electrical circuit component found in electrical switches, relays, connectors and circuit breakers.

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Electrical equipment in hazardous areas

In electrical engineering, hazardous locations (sometimes abbreviated to HazLoc, pronounced Haz·Lōk) are defined as places where fire or explosion hazards may exist due to flammable gases, flammable liquid–produced vapors, combustible liquid–produced vapors, combustible dusts, or ignitable fibers/flyings present in the air in quantities sufficient to produce explosive or ignitable mixtures.

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Electrical reactance

In electrical and electronic systems, reactance is the opposition of a circuit element to a change in current or voltage, due to that element's inductance or capacitance.

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Electrical telegraph

An electrical telegraph is a telegraph that uses electrical signals, usually conveyed via dedicated telecommunication circuit or radio.

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Electricity is the set of physical phenomena associated with the presence and motion of electric charge.

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An electromagnet is a type of magnet in which the magnetic field is produced by an electric current.

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In engineering, electromechanics combines processes and procedures drawn from electrical engineering and mechanical engineering.

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Fleetwood is a town and civil parish within the Wyre district of Lancashire, England, lying at the northwest corner of the Fylde.

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Flip-flop (electronics)

In electronics, a flip-flop or latch is a circuit that has two stable states and can be used to store state information.

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Flyback diode

A flyback diode is a diode connected across an inductor used to eliminate flyback, which is the sudden voltage spike seen across an inductive load when its supply current is suddenly reduced or interrupted.

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The gravitational force, or more commonly, g-force, is a measurement of the type of acceleration that causes a perception of weight.

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H bridge

An H bridge is an electronic circuit that enables a voltage to be applied across a load in opposite direction.

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Harvard Mark II

The Harvard Mark II, also known as Aiken Relay Calculator, was an electromechanical computer built under the direction of Howard Aiken and was finished in 1947.

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A headlamp is a lamp attached to the front of a vehicle to light the road ahead.

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Hysteresis is the dependence of the state of a system on its history.

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In electromagnetism and electronics, inductance is the property of an electrical conductor by which a change in electric current through it induces an electromotive force (voltage) in the conductor.

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Inert gas

An inert gas/noble gas is a gas which does not undergo chemical reactions under a set of given conditions.

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Inrush current

Inrush current, input surge current, or switch-on surge is the maximal instantaneous input current drawn by an electrical device when first turned on.

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John Wiley & Sons

John Wiley & Sons, Inc., also referred to as Wiley, is a global publishing company that specializes in academic publishing.

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Joseph Henry

Joseph Henry (December 17, 1797 – May 13, 1878) was an American scientist who served as the first Secretary of the Smithsonian Institution.

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Ladder logic

Ladder logic was originally a written method to document the design and construction of relay racks as used in manufacturing and process control.

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Light-emitting diode

A light-emitting diode (LED) is a two-lead semiconductor light source.

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A magnet is a material or object that produces a magnetic field.

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Magnetic core

A magnetic core is a piece of magnetic material with a high magnetic permeability used to confine and guide magnetic fields in electrical, electromechanical and magnetic devices such as electromagnets, transformers, electric motors, generators, inductors, magnetic recording heads, and magnetic assemblies.

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Magnetic field

A magnetic field is a vector field that describes the magnetic influence of electrical currents and magnetized materials.

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Magnetic reluctance

Magnetic reluctance, or magnetic resistance, is a concept used in the analysis of magnetic circuits.

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Mercury (element)

Mercury is a chemical element with symbol Hg and atomic number 80.

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Mercury relay

A mercury relay (mercury displacement relay, mercury contactor) is a relay that uses mercury as the switching element.

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A microprocessor is a computer processor that incorporates the functions of a central processing unit on a single integrated circuit (IC), or at most a few integrated circuits.

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Moving parts

The moving parts of a machine are those parts of it that move.

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Nanoelectromechanical relay

A nanoelectromechanical (NEM) relay is an electrically actuated switch that is built on the nanometer scale using semiconductor fabrication techniques.

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Number One Electronic Switching System

The Number One Electronic Switching System (1ESS) was the first large-scale stored program control (SPC) telephone exchange or electronic switching system in the Bell System.

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In electronics, an opto-isolator, also called an optocoupler, photocoupler, or optical isolator, is a component that transfers electrical signals between two isolated circuits by using light.

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In an electric power system, overcurrent or excess current is a situation where a larger than intended electric current exists through a conductor, leading to excessive generation of heat, and the risk of fire or damage to equipment.

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Ozone, or trioxygen, is an inorganic molecule with the chemical formula.

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A photodiode is a semiconductor device that converts light into an electrical current.

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Printed circuit board

A printed circuit board (PCB) mechanically supports and electrically connects electronic components or electrical components using conductive tracks, pads and other features etched from one or more sheet layers of copper laminated onto and/or between sheet layers of a non-conductive substrate.

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Programmable logic controller

A programmable logic controller (PLC), or programmable controller is an industrial digital computer which has been ruggedized and adapted for the control of manufacturing processes, such as assembly lines, or robotic devices, or any activity that requires high reliability control and ease of programming and process fault diagnosis.

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Protective relay

In electrical engineering, a protective relay is a relay device designed to trip a circuit breaker when a fault is detected.

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Race condition

A race condition or race hazard is the behavior of an electronics, software, or other system where the output is dependent on the sequence or timing of other uncontrollable events.

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Railway signalling

Railway signalling is a system used to direct railway traffic and keep trains clear of each other at all times.

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Reed relay

A reed relay is a type of relay that uses an electromagnet to control one or more reed switches.

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Reed switch

The reed switch is an electrical switch operated by an applied magnetic field.

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A relay is an electrically operated switch.

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Relay logic

Relay logic is a method of implementing combinational logic in electrical control circuits by using several electrical relays wired in a particular configuration.

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Remanence or remanent magnetization or residual magnetism is the magnetization left behind in a ferromagnetic material (such as iron) after an external magnetic field is removed.

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Resistance thermometer

Resistance thermometers, also called resistance temperature detectors (RTDs), are sensors used to measure temperature.

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Samuel Morse

Samuel Finley Breese Morse (April 27, 1791 – April 2, 1872) was an American painter and inventor. After having established his reputation as a portrait painter, in his middle age Morse contributed to the invention of a single-wire telegraph system based on European telegraphs. He was a co-developer of the Morse code and helped to develop the commercial use of telegraphy.

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A semiconductor material has an electrical conductivity value falling between that of a conductor – such as copper, gold etc.

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Sequential logic

In digital circuit theory, sequential logic is a type of logic circuit whose output depends not only on the present value of its input signals but on the sequence of past inputs, the input history.

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Shock (mechanics)

A mechanical or physical shock is a sudden acceleration caused, for example, by impact, drop, kick, earthquake, or explosion.

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Silver is a chemical element with symbol Ag (from the Latin argentum, derived from the Proto-Indo-European ''h₂erǵ'': "shiny" or "white") and atomic number 47.

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Silver oxide

Silver(I) oxide is the chemical compound with the formula Ag2O.

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A snubber is a device used to suppress ("snub") a phenomenon such as voltage transients in electrical systems, pressure transients in fluid systems (caused by for example water hammer) or excess force or rapid movement in mechanical systems.

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Solid-state electronics

Solid-state electronics means semiconductor electronics; electronic equipment using semiconductor devices such as semiconductor diodes, transistors, and integrated circuits (ICs).

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Solid-state relay

A solid-state relay (SSR) is an electronic switching device that switches on or off when a small external voltage is applied across its control terminals.

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Spring (device)

A spring is an elastic object that stores mechanical energy.

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Stepping switch

In electrical controls, a stepping switch or stepping relay, also known as a uniselector, is an electromechanical device that switches an input signal path to one of several possible output paths, directed by a train of electrical pulses.

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Strowger switch

The Strowger switch is the first commercially successful electromechanical stepping switch telephone exchange system.

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In electrical engineering, a switch is an electrical component that can "make" or "break" an electrical circuit, interrupting the current or diverting it from one conductor to another.

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Telegraphy (from Greek: τῆλε têle, "at a distance" and γράφειν gráphein, "to write") is the long-distance transmission of textual or symbolic (as opposed to verbal or audio) messages without the physical exchange of an object bearing the message.

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Telephone exchange

A telephone exchange is a telecommunications system used in the public switched telephone network or in large enterprises.

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A thermocouple is an electrical device consisting of two dissimilar electrical conductors forming electrical junctions at differing temperatures.

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A thyristor is a solid-state semiconductor device with four layers of alternating P- and N-type materials.

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A transceiver is a device comprising both a transmitter and a receiver that are combined and share common circuitry or a single housing.

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A transistor is a semiconductor device used to amplify or switch electronic signals and electrical power.

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Transistor–transistor logic

Transistor–transistor logic (TTL) is a logic family built from bipolar junction transistors.

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Transmission line

In communications and electronic engineering, a transmission line is a specialized cable or other structure designed to conduct alternating current of radio frequency, that is, currents with a frequency high enough that their wave nature must be taken into account.

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TRIAC, from triode for alternating current, is a generic trademark for a three terminal electronic component that conducts current in either direction when triggered.

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United Kingdom

The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain,Usage is mixed with some organisations, including the and preferring to use Britain as shorthand for Great Britain is a sovereign country in western Europe.

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United States Department of the Army

The Department of the Army (DA) is one of the three military departments within the Department of Defense of the United States of America.

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Vacuum is space devoid of matter.

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Voltage spike

In electrical engineering, spikes are fast, short duration electrical transients in voltage (voltage spikes), current (current spikes), or transferred energy (energy spikes) in an electrical circuit.

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Wilhelm Eduard Weber

Wilhelm Eduard Weber (24 October 1804 – 23 June 1891) was a German physicist and, together with Carl Friedrich Gauss, inventor of the first electromagnetic telegraph.

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Wire spring relay

A wire spring relay is a type of relay, that has springs made from drawn wires of nickel silver, rather than cut from flat sheet metal as in the flat-spring relay.

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A yoke is a wooden beam normally used between a pair of oxen or other animals to enable them to pull together on a load when working in pairs, as oxen usually do; some yokes are fitted to individual animals.

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Z2 (computer)

The Z2 was a mechanical and relay computer completed by Konrad Zuse in 1940.

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Z3 (computer)

The Z3 was a German electromechanical computer designed by Konrad Zuse.

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3000 Type Relay, 600 Type Relay, Bistable relay, Coaxial relay, Control relay, Electric relay, Electrical relay, Electromechanical relay, Impulse relay, Keep relay, Latching relay, Mercury-wetted relay, Overload protection relay, Relay switch, Relays, Stay relay.


[1] https://en.wikipedia.org/wiki/Relay

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