Electrical Symbols — Switches and Relays

The vector stencils library "Transformers and windings" contains 29 element symbols of transformers, windings, couplers, metering devices, transductors, magnetic cores, chokes, and a variometer.
Use it to design the electromechanical device schematics and electronic circuit diagrams.
"A transformer is an electrical device that transfers energy between two circuits through electromagnetic induction. Transformers may be used in step-up or step-down voltage conversion, which 'transforms' an AC voltage from one voltage level on the input of the device to another level at the output terminals. This special function of transformers can provide control of specified requirements of current level as an alternating current source, or it may be used for impedance matching between mismatched electrical circuits to effect maximum power transfer between the circuits.
A transformer most commonly consists of two windings of wire that are wound around a common core to induce tight electromagnetic coupling between the windings. The core material is often a laminated iron core. The coil that receives the electrical input energy is referred to as the primary winding, while the output coil is called the secondary winding.
An alternating electric current flowing through the primary winding (coil) of a transformer generates an electromagnetic field in its surroundings and a varying magnetic flux in the core of the transformer. By electromagnetic induction this magnetic flux generates a varying electromotive force in the secondary winding, resulting in a voltage across the output terminals. If a load impedance is connected across the secondary winding, a current flows through the secondary winding drawing power from the primary winding and its power source." [Transformer. Wikipedia]
"An electromagnetic coil (or simply a "coil") is formed when a conductor is wound around a core or form to create an inductor or electromagnet. When electricity is passed through a coil, it generates a magnetic field. One loop of wire is usually referred to as a turn or a winding, and a coil consists of one or more turns. For use in an electronic circuit, electrical connection terminals called taps are often connected to a coil. Coils are often coated with varnish or wrapped with insulating tape to provide additional insulation and secure them in place. A completed coil assembly with one or more set of coils and taps is often called the windings.
Windings are used in transformers, electric motors, inductors, solenoids, loudspeakers, and many other applications." [Electromagnetic coil. Wikipedia]
The shapes example "Design elements - Transformers and windings" was drawn using the ConceptDraw PRO diagramming and vector drawing software extended with the Electrical Engineering solution from the Engineering area of ConceptDraw Solution Park.

The vector stencils library "Lamps, acoustics, readouts" contains 35 element symbols of lamps, acoustic components, electrical measuring instruments for drawing electrical schematics and electronic circuit diagrams.
"Electrical measurements are the methods, devices and calculations used to measure electrical quantities. Measurement of electrical quantities may be done to measure electrical parameters of a system. Using transducers, physical properties such as temperature, pressure, flow, force, and many others can be converted into electrical signals, which can then be conveniently measured and recorded." [Electrical measurements. Wikipedia]
"A lamp is a replaceable component such as an incandescent light bulb, which is designed to produce light from electricity." [Lamp (electrical component). Wikipedia]
"An electric bell is a mechanical bell that... functions by means of an electromagnet. When an electric current is applied, it produces a repetitive buzzing or clanging sound." [Electric bell. Wikipedia]
"A buzzer or beeper is an audio signalling device, which may be mechanical, electromechanical, or piezoelectric." [Buzzer. Wikipedia]
"Electronic sirens incorporate circuits such as oscillators, modulators, and amplifiers to synthesize a selected siren tone (wail, yelp, pierce/ priority/ phaser, hi-lo, scan, airhorn, manual, and a few more) which is played through external speakers." [Siren (noisemaker). Wikipedia]
"A microphone (colloquially called a mic or mike...) is an acoustic-to-electric transducer or sensor that converts sound in air into an electrical signal. ...
Most microphones today use electromagnetic induction (dynamic microphone), capacitance change (condenser microphone) or piezoelectric generation to produce an electrical signal from air pressure variations." [Microphone. Wikipedia]
The symbols example "Design elements - Lamps, acoustics, readouts" was drawn using the ConceptDraw PRO diagramming and vector drawing software extended with the Electrical Engineering solution from the Engineering area of ConceptDraw Solution Park.

The vector stencils library "Transmission paths" contains 43 symbols of power transmission paths, electronic circuits, bus connectors and elbows, terminals, junctions, and concentrators.
Use it to annotate electrical diagrams, electronic schematics and circuit diagrams.
"A physical medium in data communications is the transmission path over which a signal propagates.
Many transmission media are used as communications channel.
For telecommunications purposes in the United States, Federal Standard 1037C, transmission media are classified as one of the following:
(1) Guided (or bounded) - waves are guided along a solid medium such as a transmission line.
(2) Wireless (or unguided) - transmission and reception are achieved by means of an antenna.
One of the most common physical medias used in networking is copper wire. Copper wire to carry signals to long distances using relatively low amounts of power. The unshielded twisted pair (UTP) is eight strands of copper wire, organized into four pairs.
Another example of a physical medium is optical fiber, which has emerged as the most commonly used transmission medium for long-distance communications. Optical fiber is a thin strand of glass that guides light along its length.
Multimode and single mode are two types of commonly used optical fiber. Multimode fiber uses LEDs as the light source and can carry signals over shorter distances, about 2 kilometers. Single mode can carry signals over distances of tens of miles.
Wireless media may carry surface waves or skywaves, either longitudinally or transversely, and are so classified.
In both communications, communication is in the form of electromagnetic waves. With guided transmission media, the waves are guided along a physical path; examples of guided media include phone lines, twisted pair cables, coaxial cables, and optical fibers. Unguided transmission media are methods that allow the transmission of data without the use of physical means to define the path it takes. Examples of this include microwave, radio or infrared. Unguided media provide a means for transmitting electromagnetic waves but do not guide them; examples are propagation through air, vacuum and seawater.
The term direct link is used to refer to the transmission path between two devices in which signals propagate directly from transmitters to receivers with no intermediate devices, other than amplifiers or repeaters used to increase signal strength. This term can apply to both guided and unguided media.
A transmission may be simplex, half-duplex, or full-duplex.
In simplex transmission, signals are transmitted in only one direction; one station is a transmitter and the other is the receiver. In the half-duplex operation, both stations may transmit, but only one at a time. In full duplex operation, both stations may transmit simultaneously. In the latter case, the medium is carrying signals in both directions at same time." [Transmission medium. Wikipedia]
The shapes example "Design elements - Transmission paths" was drawn using the ConceptDraw PRO diagramming and vector drawing software extended with the Electrical Engineering solution from the Engineering area of ConceptDraw Solution Park.

The vector stencils library "Cisco optical" contains 19 symbols of optical devices for drawing Cisco computer network diagrams.
"Fiber-optic communication is a method of transmitting information from one place to another by sending pulses of light through an optical fiber. The light forms an electromagnetic carrier wave that is modulated to carry information. ... Because of its advantages over electrical transmission, optical fibers have largely replaced copper wire communications in core networks in the developed world. Optical fiber is used by many telecommunications companies to transmit telephone signals, Internet communication, and cable television signals. ...
The process of communicating using fiber-optics involves the following basic steps: Creating the optical signal involving the use of a transmitter, relaying the signal along the fiber, ensuring that the signal does not become too distorted or weak, receiving the optical signal, and converting it into an electrical signal." [Fiber-optic communication. Wikipedia]
The symbols example "Cisco optical - Vector stencils library" was created using the ConceptDraw PRO diagramming and vector drawing software extended with the Cisco Network Diagrams solution from the Computer and Networks area of ConceptDraw Solution Park.
www.conceptdraw.com/ solution-park/ computer-networks-cisco