Electrical

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General

See also Physics#Electromagnetism, Hardware, Computing, Living




  • E=Pt
    • Energy = power x time


  • Ep = mgh
    • Gravitational potential energy (joules) = mass (kg) x gravitational field strength (g, N/kg) x height (m)
  • Ek = 1/2 mv
    • kinetic energy = 1/2 x mass x speed^2
  • Eh = cm∆T
    • Heat energy = heat capacity (Joules) x mass x change in temp.
  • Eh = mLf
    • Heat energy = mass x latent heat change property of material
  • a = V-u / t
    • acceleration = change in velocity / time
  • v = d/t
    • velocity = distance / time


  • Rt (series) = R1 + R2 + R3 ...
  • Rt (parallel x2) = R1xR2 / R1+R2
  • Rt (parallel x2+) = 1 / 1/Ra + 1/R2 + 1/R3
  • v=f x λ

Q=It









  • https://en.wikipedia.org/wiki/Coulomb - a fundamental unit of electrical charge, and is also the SI derived unit of electric charge (symbol: Q or q). It is equal to the charge of approximately 6.241×1018 electrons. Its SI definition is the charge transported by a constant current of one ampere in one second. One coulomb is also the amount of excess charge on a capacitor of one farad charged to a potential difference of one volt.


  • https://en.wikipedia.org/wiki/Ampère's_force_law - In magnetostatics, the force of attraction or repulsion between two current-carrying wires (see first figure below) is often called Ampère's force law. The physical origin of this force is that each wire generates a magnetic field, following the Biot–Savart law, and the other wire experiences a magnetic force as a consequence, following the Lorentz force law.





  • https://en.wikipedia.org/wiki/Direct_current - the unidirectional flow of electric charge. A battery is a good example of a DC power supply. Direct current may flow in a conductor such as a wire, but can also flow through semiconductors, insulators, or even through a vacuum as in electron or ion beams. The electric current flows in a constant direction, distinguishing it from alternating current (AC). A term formerly used for this type of current was galvanic current. The abbreviations AC and DC are often used to mean simply alternating and direct, as when they modify current or voltage. Direct current may be obtained from an alternating current supply by use of a rectifier, which contains electronic elements (usually) or electromechanical elements (historically) that allow current to flow only in one direction. Direct current may be converted into alternating current with an inverter or a motor-generator set. Direct current is used to charge batteries and as power supply for electronic systems. Very large quantities of direct-current power are used in production of aluminum and other electrochemical processes. It is also used for some railways, especially in urban areas. High-voltage direct current is used to transmit large amounts of power from remote generation sites or to interconnect alternating current power grids.


  • https://en.wikipedia.org/wiki/Kirchhoff%27s_circuit_laws - are two equalities that deal with the current and potential difference (commonly known as voltage) in the lumped element model of electrical circuits. They were first described in 1845 by German physicist Gustav Kirchhoff.[1] This generalized the work of Georg Ohm and preceded the work of James Clerk Maxwell. Widely used in electrical engineering, they are also called Kirchhoff's rules or simply Kirchhoff's laws. Both of Kirchhoff's laws can be understood as corollaries of Maxwell's equations in the low-frequency limit. They are accurate for DC circuits, and for AC circuits at frequencies where the wavelengths of electromagnetic radiation are very large compared to the circuits.

Current law = At any node (junction) in an electrical circuit, the sum of currents flowing into that node is equal to the sum of currents flowing out of that node

Voltate law = The directed sum of the electrical potential differences (voltage) around any closed network is zero.


  • https://en.wikipedia.org/wiki/Inductance - the property of a conductor by which a change in current flowing through it "induces" (creates) a voltage (electromotive force) in both the conductor itself (self-inductance) and in any nearby conductors (mutual inductance).
  • https://en.wikipedia.org/wiki/Faraday's_law_of_induction - a basic law of electromagnetism predicting how a magnetic field will interact with an electric circuit to produce an electromotive force (EMF)—a phenomenon called electromagnetic induction. It is the fundamental operating principle of transformers, inductors, and many types of electrical motors, generators and solenoids. The Maxwell–Faraday equation is a generalization of Faraday's law, and is listed as one of Maxwell's equations.


  • https://en.wikipedia.org/wiki/Electrical_reactance - the opposition of a circuit element to a change in current or voltage, due to that element's inductance or capacitance. The notion of reactance is similar to electrical resistance, but it differs in several respects. In phasor analysis, reactance is used to compute amplitude and phase changes of sinusoidal alternating current going through a circuit element. It is denoted by the symbol X. An ideal resistor has zero reactance, whereas ideal inductors and capacitors have zero resistance – that is, respond to current only by reactance. The magnitude of the reactance of an inductor rises in proportion to a rise in frequency, while the magnitude of the reactance of a capacitor decreases in proportion to a rise in frequency. As frequency goes up, inductive reactance also goes up and capacitive reactance goes down.



  • https://en.wikipedia.org/wiki/Transformer - a static electrical device that transfers electrical energy between two or more circuits through electromagnetic induction. A varying current in one coil of the transformer produces a varying magnetic field, which in turn induces a varying electromotive force (emf) or "voltage" in a second coil. Power can be transferred between the two coils through the magnetic field, without a metallic connection between the two circuits. Faraday's law of induction discovered in 1831 described this effect. Transformers are used to increase or decrease the alternating voltages in electric power applications.



  • https://en.wikipedia.org/wiki/Counter-electromotive_force - abbreviated counter EMF or simply CEMF, also known as back electromotive force (or back EMF), is the electromotive force or "voltage" that opposes the change in current which induced it. CEMF is the EMF caused by magnetic induction (see Faraday's law of induction, electromagnetic induction, Lenz's Law).


  • https://en.wikipedia.org/wiki/Biot–Savart_law - an equation describing the magnetic field generated by a stationary electric current. It relates the magnetic field to the magnitude, direction, length, and proximity of the electric current. The Biot–Savart law is fundamental to magnetostatics, playing a similar role to Coulomb's law in electrostatics. When magnetostatics does not apply, the Biot–Savart law should be replaced by Jefimenko's equations. The law is valid in the magnetostatic approximation, and is consistent with both Ampère's circuital law and Gauss's law for magnetism. It is named after Jean-Baptiste Biot and Félix Savart who discovered this relationship in 1820.





  • WaveDrom is Free and Open Source online digital timing diagram (waveform) rendering engine that uses javascript, HTML5 and SVG to convert WaveJSON input text description into SVG vector graphics. WaveJSON is an application of the JSON format. The purpose of WaveJSON is to provide a compact exchange format for digital timing diagrams utilized by digital HW / IC engineers.




Generation


Storage

See also Living#Fuel cell










UPG 12V 55Ah Sealed


  • https://en.wikipedia.org/wiki/Lead–acid_battery - invented in 1859 by French physicist Gaston Planté and is the oldest type of rechargeable battery. Despite having a very low energy-to-weight ratio and a low energy-to-volume ratio, its ability to supply high surge currents means that the cells have a relatively large power-to-weight ratio. These features, along with their low cost, make them attractive for use in motor vehicles to provide the high current required by automobile starter motors.

As they are inexpensive compared to newer technologies, lead–acid batteries are widely used even when surge current is not important and other designs could provide higher energy densities. Large-format lead–acid designs are widely used for storage in backup power supplies in cell phone towers, high-availability settings like hospitals, and stand-alone power systems. For these roles, modified versions of the standard cell may be used to improve storage times and reduce maintenance requirements. Gel-cells and absorbed glass-mat batteries are common in these roles, collectively known as VRLA (valve-regulated lead–acid) batteries.


  • https://en.wikipedia.org/wiki/UltraBattery - a hybrid energy storage device invented by Australia’s Commonwealth Scientific and Industrial Research Organisation (CSIRO). UltraBattery combines ultracapacitor technology with lead-acid battery technology in a single cell with a common electrolyte.







  • https://en.wikipedia.org/wiki/Electric_vehicle_battery - EVB) or traction battery is a battery used to power the propulsion of battery electric vehicles (BEVs). Vehicle batteries are usually a secondary (rechargeable) battery. Traction batteries are used in forklifts, electric golf carts, riding floor scrubbers, electric motorcycles, electric cars, trucks, vans, and other electric vehicles.

Electric-vehicle batteries differ from starting, lighting, and ignition (SLI) batteries because they are designed to give power over sustained periods of time. Deep-cycle batteries are used instead of SLI batteries for these applications. Traction batteries must be designed with a high ampere-hour capacity. Batteries for electric vehicles are characterized by their relatively high power-to-weight ratio, energy-to-weight ratio and energy density; smaller, lighter batteries reduce the weight of the vehicle and improve its performance. Compared to liquid fuels, most current battery technologies have much lower specific energy, and this often impacts the maximal all-electric range of the vehicles. However, metal-air batteries have high specific energy because the cathode is provided by the surrounding oxygen in the air. Rechargeable batteries used in electric vehicles include lead–acid ("flooded", deep-cycle, and VRLA), NiCd, nickel–metal hydride, lithium-ion, Li-ion polymer, and, less commonly, zinc–air and molten-salt batteries. The amount of electricity (i.e. electric charge) stored in batteries is measured in ampere hours or in coulombs, with the total energy often measured in watt hours.






Testing

Supply and conversion


  • https://en.wikipedia.org/wiki/Rectifier - an electrical device that converts alternating current (AC), which periodically reverses direction, to direct current (DC), which flows in only one direction.




  • https://en.wikipedia.org/wiki/Transmission_line - 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. Transmission lines are used for purposes such as connecting radio transmitters and receivers with their antennas (they are then called feed lines or feeders), distributing cable television signals, trunklines routing calls between telephone switching centres, computer network connections and high speed computer data buses.



  • https://en.wikipedia.org/wiki/Power_inverter - an electronic device or circuitry that changes direct current (DC) to alternating current (AC). The input voltage, output voltage and frequency, and overall power handling depend on the design of the specific device or circuitry. The inverter does not produce any power; the power is provided by the DC source. A power inverter can be entirely electronic or may be a combination of mechanical effects (such as a rotary apparatus) and electronic circuitry. Static inverters do not use moving parts in the conversion process.







Circuits






  • https://en.wikibooks.org/wiki/Signals_and_Systems - This book is about the study of engineering signals and systems, from a discipline-neutral approach. It is a fundamental starting point in the field of engineering, and serves as the basic material that other advanced books in the engineering subject area are based. This book looks at the concepts of systems, serving as an introduction to systems theory. Also, this book examines signals, and the way that signals interact with physical systems. While this book strives to be discipline-neutral, it currently is focused strongly on electrical engineering concepts. It is hoped that this book will be expanded to include information from other disciplines as well.


Components


  • https://en.wikipedia.org/wiki/Terminal_(electronics) - the point at which a conductor from an electrical component, device or network comes to an end and provides a point of connection to external circuits. A terminal may simply be the end of a wire or it may be fitted with a connector or fastener. In network analysis, terminal means a point at which connections can be made to a network in theory and does not necessarily refer to any real physical object. In this context, especially in older documents, it is sometimes called a pole.


  • https://en.wikipedia.org/wiki/Electrical_ballast - a device placed in line with the load to limit the amount of current in an electrical circuit. It may be a fixed or variable resistor. Ballasts vary greatly in complexity. They may be as simple as a resistor, inductor or capacitor (or a combination of these) wired in series with the lamp; or as complex as the electronic ballasts used in compact fluorescent lamps and high-intensity discharge lamps.



  • Two-terminal non-linear circuit elements.svg - Relations between the four fundamental electronic variables (voltage, charge, current, flux) and devices that implement these relations (resistor, capacitor, inductor, memristor).


  • https://en.wikipedia.org/wiki/Inductor - also called a coil, choke or reactor, is a passive two-terminal electrical component that stores energy in a magnetic field when electric current flows through it.[1] An inductor typically consists of an insulated wire wound into a coil around a core.

When the current flowing through an inductor changes, the time-varying magnetic field induces a voltage in the conductor, described by Faraday's law of induction. According to Lenz's law, the direction of induced electromotive force (e.m.f.) opposes the change in current that created it. As a result, inductors oppose any changes in current through them.

An inductor is characterized by its inductance, which is the ratio of the voltage to the rate of change of current. In the International System of Units (SI), the unit of inductance is the henry (H) named for 19th century American scientist Joseph Henry. In the measurement of magnetic circuits, it is equivalent to weber/ampere. Inductors have values that typically range from 1 µH (10−6 H) to 20 H. Many inductors have a magnetic core made of iron or ferrite inside the coil, which serves to increase the magnetic field and thus the inductance. Along with capacitors and resistors, inductors are one of the three passive linear circuit elements that make up electronic circuits. Inductors are widely used in alternating current (AC) electronic equipment, particularly in radio equipment. They are used to block AC while allowing DC to pass; inductors designed for this purpose are called chokes. They are also used in electronic filters to separate signals of different frequencies, and in combination with capacitors to make tuned circuits, used to tune radio and TV receivers.


  • https://en.wikipedia.org/wiki/Capacitor - layers of insulators and conductors. AC will jump the gap because of inductance. smaller caps block lower frequencies because bass frequencies are closer to DC.








  • https://en.wikipedia.org/wiki/Semiconductor - A semiconductor material has an electrical conductivity value falling between that of a conductor – such as copper, gold etc. – and an insulator, such as glass. Their resistance decreases as their temperature increases, which is behavior opposite to that of a metal. Their conducting properties may be altered in useful ways by the deliberate, controlled introduction of impurities ("doping") into the crystal structure. Where two differently-doped regions exist in the same crystal, a semiconductor junction is created. The behavior of charge carriers which include electrons, ions and electron holes at these junctions is the basis of diodes, transistors and all modern electronics.


  • https://en.wikipedia.org/wiki/Semiconductor_device - electronic components that exploit the electronic properties of semiconductor materials, principally silicon, germanium, and gallium arsenide, as well as organic semiconductors. Semiconductor devices have replaced thermionic devices (vacuum tubes) in most applications. They use electronic conduction in the solid state as opposed to the gaseous state or thermionic emission in a high vacuum. Semiconductor devices are manufactured both as single discrete devices and as integrated circuits (ICs), which consist of a number—from a few (as low as two) to billions—of devices manufactured and interconnected on a single semiconductor substrate, or wafer.



  • https://en.wikipedia.org/wiki/Transistor - a semiconductor device used to amplify and switch electronic signals and electrical power. It is composed of semiconductor material with at least three terminals for connection to an external circuit. A voltage or current applied to one pair of the transistor's terminals changes the current through another pair of terminals. Because the controlled (output) power can be higher than the controlling (input) power, a transistor can amplify a signal. Today, some transistors are packaged individually, but many more are found embedded in integrated circuits.



  • https://en.wikipedia.org/wiki/Bipolar_junction_transistor - bipolar transistor or BJT) is a type of transistor that uses both electron and hole charge carriers. In contrast, unipolar transistors, such as field-effect transistors, only use one kind of charge carrier. For their operation, BJTs use two junctions between two semiconductor types, n-type and p-type. BJTs are manufactured in two types, NPN and PNP, and are available as individual components, or fabricated in integrated circuits, often in large numbers. The basic function of a BJT is to amplify current. This allows BJTs to be used as amplifiers or switches, giving them wide applicability in electronic equipment, including computers, televisions, mobile phones, audio amplifiers, industrial control, and radio transmitters.


  • https://en.wikipedia.org/wiki/Field-effect_transistor - a transistor that uses an electric field to control the electrical behaviour of the device. FETs are also known as unipolar transistors since they involve single-carrier-type operation. Many different implementations of field effect transistors exist. Field effect transistors generally display very high input impedance at low frequencies. The conductivity between the drain and source terminals is controlled by an electric field in the device, which is generated by the voltage difference between the body and the gate of the device.


  • https://en.wikipedia.org/wiki/MOSFET - metal–oxide–semiconductor field-effect transistor (MOSFET, MOS-FET, or MOS FET) is a type of transistor used for amplifying or switching electronic signals. Although the MOSFET is a four-terminal device with source (S), gate (G), drain (D), and body (B) terminals, the body (or substrate) of the MOSFET is often connected to the source terminal, making it a three-terminal device like other field-effect transistors. Because these two terminals are normally connected to each other (short-circuited) internally, only three terminals appear in electrical diagrams. The MOSFET is by far the most common transistor in both digital and analog circuits, though the bipolar junction transistor was at one time much more common.



Logic



  • https://en.wikipedia.org/wiki/Functional_completeness - means that every possible logic gate can be realized as a network of gates of the types prescribed by the set. In particular, all logic gates can be assembled from either only binary NAND gates, or only binary NOR gates.



Actuator

  • https://en.wikipedia.org/wiki/Actuator - a component of a machine that is responsible for moving and controlling a mechanism or system, for example by opening a valve. In simple terms, it is a "mover". An actuator requires a control signal and a source of energy. The control signal is relatively low energy and may be electric voltage or current, pneumatic or hydraulic pressure, or even human power. Its main energy source may be an electric current, hydraulic fluid pressure, or pneumatic pressure. When it receives a control signal, an actuator responds by converting the signal's energy into mechanical motion. An actuator is the mechanism by which a control system acts upon an environment. The control system can be simple (a fixed mechanical or electronic system), software-based (e.g. a printer driver, robot control system), a human, or any other input.


  • https://en.wikipedia.org/wiki/Linear_actuator - an actuator that creates motion in a straight line, in contrast to the circular motion of a conventional electric motor. Linear actuators are used in machine tools and industrial machinery, in computer peripherals such as disk drives and printers, in valves and dampers, and in many other places where linear motion is required. Hydraulic or pneumatic cylinders inherently produce linear motion. Many other mechanisms are used to generate linear motion from a rotating motor.

Filters


Analog electronics



Digital





Logics

  • https://en.wikipedia.org/wiki/Logic_family - may refer to one of two related concepts. A logic family of monolithic digital integrated circuit devices is a group of electronic logic gates constructed using one of several different designs, usually with compatible logic levels and power supply characteristics within a family. Many logic families were produced as individual components, each containing one or a few related basic logical functions, which could be used as "building-blocks" to create systems or as so-called "glue" to interconnect more complex integrated circuits. A "logic family" may also refer to a set of techniques used to implement logic within VLSI integrated circuits such as central processors, memories, or other complex functions. Some such logic families use static techniques to minimize design complexity. Other such logic families, such as domino logic, use clocked dynamic techniques to minimize size, power consumption and delay.


  • https://en.wikipedia.org/wiki/7400_series - of transistor–transistor logic (TTL) integrated circuits are the most popular family of TTL integrated circuit logic. Quickly replacing diode–transistor logic, it was used to build the mini and mainframe computers of the 1960s and 1970s. Several generations of pin-compatible descendants of the original family have since become de facto standard electronic components.




DSP


Integrated circuits

See also Computer#Single-board microcontroller



  • https://en.wikipedia.org/wiki/Programmable_logic_controller - PLC), or programmable controller is an industrial digital computer which has been ruggedised 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.

They were first developed in the automobile industry to provide flexible, ruggedised and easily programmable controllers to replace hard-wired relays and timers. Since then they have been widely adopted as high-reliability automation controllers suitable for harsh environments. A PLC is an example of a "hard" real-time system since output results must be produced in response to input conditions within a limited time, otherwise unintended operation will result.


  • https://en.wikipedia.org/wiki/Very-large-scale_integration - the process of creating an integrated circuit by combining thousands of transistors into a single chip. VLSI began in the 1970s when complex semiconductor and communication technologies were being developed. The microprocessor is a VLSI device. Before the introduction of VLSI technology most ICs had a limited set of functions they could perform. An electronic circuit might consist of a CPU, ROM, RAM and other glue logic. VLSI lets IC makers add all of these into one chip.




Software

  • https://en.wikipedia.org/wiki/Electronic_design_automation - a category of software tools for designing electronic systems such as printed circuit boards and integrated circuits. The tools work together in a design flow that chip designers use to design and analyze entire semiconductor chips. EDA is also referred to as electronic computer-aided design (ECAD).
  • https://en.wikipedia.org/wiki/Design_flow_(EDA) - the explicit combination of electronic design automation tools to accomplish the design of an integrated circuit. Moore's law has driven the entire IC implementation RTL to GDSII design flows from one which uses primarily stand-alone synthesis, placement, and routing algorithms to an integrated construction and analysis flows for design closure. The challenges of rising interconnect delay led to a new way of thinking about and integrating design closure tools.


  • Open Collector - carries listings and news for free EDA software and circuit designs. Open Collector supports gEDA.


TinyCAD

gEDA

  • gEDA project has produced and continues working on a full GPL'd suite and toolkit of Electronic Design Automation tools. These tools are used for electrical circuit design, schematic capture, simulation, prototyping, and production. Currently, the gEDA project offers a mature suite of free software applications for electronics design, including schematic capture, attribute management, bill of materials (BOM) generation, netlisting into over 20 netlist formats, analog and digital simulation, and printed circuit board (PCB) layout. The gEDA project was started because of the lack of free EDA tools for POSIX systems with the primary purpose of advancing the state of free hardware or open source hardware. The suite is mainly being developed on the GNU/Linux platform with some development effort going into making sure the tools run on other platforms as well.

XCircuit

  • XCircuit - a UNIX/X11 (and Windows, or Windows using Cygwin and the Cygwin X-Server) program for drawing publishable-quality electrical circuit schematic diagrams and related figures, and produce circuit netlists through schematic capture. XCircuit regards circuits as inherently hierarchical, and writes both hierarchical PostScript output and hierarchical SPICE netlists. Circuit components are saved in and retrieved from libraries which are fully editable. XCircuit does not separate artistic expression from circuit drawing; it maintains flexiblity in style without compromising the power of schematic capture. XCircuit is flexible enough to be used as a generic program for drawing just about anything, and is competitive with powerful programs such as "xfig". It is especially good for any task requiring repeated use of a standard set of graphical objects, including architectural drawing, printed circuit board layouts, and (my personal favorite) music typography (see my Music Page for examples).

FreePCB

  • FreePCB - a free, open-source PCB editor for Microsoft Windows, released under the GNU General Public License. It was designed to be easy to learn and easy to use, yet capable of professional-quality work.


KiCad EDA

  • KiCad EDA - A Cross Platform and Open Source Electronics Design Automation Suite [9]

EasyEDA

Services

  • CircuitBee provides a platform for you to share live versions of your circuit schematics on your websites, blogs or forums.
  • CircuitLab - online schematic editor & circuit simulator
  • upverter - Create hardware better, faster. Design open source and private projects as a team. Draw schematics, layout PCBs and review designs together.

HDL

Simulation


  • Qucs - Quite Universal Circuit Simulator, an integrated circuit simulator which means you are able to setup a circuit with a graphical user interface (GUI) and simulate the large-signal, small-signal and noise behaviour of the circuit. After that simulation has finished you can view the simulation results on a presentation page or window.


  • spicesound - Simulating Analog Audio Cicuits, an extension to ngspice that provides a libsndfile voltage source and the possibility to write ngspice's output in audio-file format. Ngspice is a mixed-level/mixed-signal circuit simulator, based on Berkeley Spice3F5 and developed openly as ngspice sourceforge project. Libsndfile is a C library for reading and writing files containing sampled sound; released in source code format under the GNU Lesser General Public License.



PCB



Circuit printers

Connectors





Wire and cable


12/24v system






"Leisure batteries differ in construction from vehicle starter batteries because they are designed for different jobs, and consequently require a different charging regime.

"Fixed voltage battery chargers won't achieve full re-charging of a leisure battery because the lead plates are thicker, so charging has to take place in controlled stages with the voltage level being automatically adjusted throughout to ensure full charge absoprtion. This is where dedicated multi-stage or 'intelligent' chargers need to be used to ensure your battery receives a full, deep charge and its serviceable lifetime is maximised.

"As a rule of the thumb the charger output current should be around 10-15% of your battery's Ah capacity."

  • Capacitor

"you'll find that the spec says you need a BIG electrolytic cap across your battery, you don't need one for a portable system; it is recommended because class D amplifiers can backfeed current. Deep Cycle batteries cope with this; the capacitor is for car setups where the deep cycle battery for the amp is split charged and is only there to run the system full blast for an hour without the engine running."

Projects





Electrical engineering

See also Computing, etc.



Tutorials


  • Hackster.io gives professionals and hobbyists the resources they need to build hardware, the easy way.
  • EEVblog Electronics Resource Wiki - This resource site contains useful links and information related to all aspects of Electronics Engineering and associated electronics design.


  • Basic Electronics Tutorials provides students and beginners alike studying Electronics a good Basic Electronics Tutorials and information to help develop a knowledge and understanding of the subject of Electronics.


Safety



Shopping




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