In this post, you will find everything regarding electric coils on the internet.
You will learn:
An electric coil, also known as an electromagnetic coil, is made up of a series of conductive wires wrapped around a core that can be cylindrical, toroidal, or disk-shaped, often composed of ferromagnetic materials. This fundamental electronic component is known for providing inductance in electrical circuits, a property crucial for resisting the current flow.
Electric coils are available in various types, each distinguished by attributes such as wire gauge, coil diameter, wire length, loop count, and core material. Core materials range from air, iron, and steel to ceramic and iron-based formless tape. The selection depends on the material's permeability, crucial for its ability to enhance and support the magnetic field efficiently.
Electric coils play a vital role in devices like electric motors, generators, inductors, and electromagnets. They act as conductors of electricity, effectively delivering electrical flow to electric motors, proving to be a reliable and steady method for induction.
Electric coils are widely used in industrial manufacturing, medical equipment, and systems that supply electricity to residential and commercial buildings. Due to their broad range of applications, coils are designed to meet the specific needs of various processes and requirements.
Medical equipment must adhere to stringent standards, especially for components used in medical treatments. Manufacturers typically produce coils that comply with cleanroom standards to ensure high levels of cleanliness. Medical coils are made from a variety of materials to suit different applications, and they require extremely precise inner and outer diameter tolerances to ensure reliable performance in critical situations.
Military-grade coils must be reliable, accurate, instantly responsive, and capable of functioning under harsh and hazardous conditions. They are utilized in various military applications, including guidance systems, navigation controls, and sensors.
The transportation industry extensively utilizes electric coils in various applications. They are used in railroad track transformers, lighting transformers, armatures, and signaling devices. Additionally, electric coils are essential in the production of electric locomotives, where they are specifically designed to endure the vibrations from continuous use.
Manufacturing components for the energy industry presents challenges, especially since many energy extraction sites are located in remote areas. Oil platforms, for instance, need reliable energy sources for electricity generation. Electric coils used in these settings are specially engineered to withstand harsh environments and demanding conditions.
With the rapid proliferation of electronic devices, the production of electric coils has required significant resources to perfect and design coils to meet growing demand. Coils used in circuit boards are typically made from finely wound wire and are essential for manufacturing laminated transformers and toroids.
Electric coils designed for wind turbines are engineered to handle generators that produce between 100 W and over 1 MW. These coils are built to withstand temperatures up to 200°C while maintaining high performance. They are made from lightweight materials and are insulated to protect against leakage and damage.
A flowmeter measures the volume of liquid or gas flowing through a pipe, providing accurate monitoring and control for precise flow calculations. Bobbin-mounted flowmeter coils are custom-molded and shaped to fit the radius of the tube where flow is measured. Since these coils are non-mechanical, they are resistant to wear and abrasion.
A basic part of an automobile is an ignition coil that changes the energy from the battery to the thousands of volts required to create a spark in the spark plugs to ignite the fuel for the engine. As with most coils, ignition coils consist of two sets of copper wires that are wrapped around an iron core. The electric energy from the core is transferred to the distributor and on to the spark plugs. The primary winding of the coil is heavy wire, which is surrounded by secondary windings of lighter smaller wire. The concept of the ignition coil goes back hundreds of years and was adapted for use in the first automobiles.
A traffic light sensor consists of a coil with an attached inductance meter. When a car enters the sensor's field, it acts as the core of the inductor, altering the coil's inductance. This change signals the traffic light that a vehicle is present.
Transformers have revolutionized the delivery of electricity. Initially, electricity was supplied as direct current (DC), which required a vast network of transfer stations for long-distance transmission. The advent of alternating current (AC) allowed electricity to be transmitted over long distances with fewer intermediate stations. The transformer was crucial to this advancement.
Transformers enable the transmission of AC at high voltage and low current, reducing energy loss in the lines. They convert high voltage to low voltage and adjust the current's energy level. Transformers use multiple coils and electromagnetic flux, with primary windings on one side and secondary windings on the other, to conduct electricity.
An electric guitar coil is a type of transducer that converts the vibrations of the strings into electrical signals. The most common designs include single coils and dual coils, such as the humbucker. In the dual-coil design, two coils work together to "buck the hum" by canceling out electrical interference. These pickups create a magnetic field around the guitar strings to capture their vibrations.
Although electric coils are among the simplest electrical components, they are meticulously engineered for their specific applications. An electrical coil typically consists of a core with wiring wrapped around it, though some coils may have just wound wires without a core. Both the wire and its winding play crucial roles in determining the coil's performance and functionality.
The shape and dimensions of the wire in a coil are selected based on the specific function it needs to perform. Key factors in wire selection include inductance, energy loss, insulation strength, and the power of the magnetic field.
To achieve maximum efficiency, coils are designed to minimize material usage and volume. A critical metric is the fill factor, which represents the ratio of the conductor area to the winding space. Since round wires always leave some gaps, compounded by insulation and multiple layers, the fill factor ranges between 0.01 and 0.05. Using rectangular, square, or flat wires can help increase the fill factor by reducing these gaps.
Fill factors are categorized based on the ratio between the cross-sectional area of the wire and the cross-sectional area of the coil. This ratio is calculated to range between 0.1 and 0.5, with high, intermediate, and low fill factor classifications.
Increasing the density of wire packing reduces air gaps and enhances the fill factor, which boosts the efficiency and conductivity of an electrical device. For optimal packing of round wires, the top layer should fill the grooves of the lower layer, covering approximately 300° of the coil’s circumference.
Winding wire is an insulated conductor designed to convert electrical energy into magnetic energy. Typically, this wire is either coated copper or aluminum with a thin layer of insulation. Copper is often the preferred choice for most electric coils due to its superior chemical, physical, and mechanical properties. For applications involving high temperatures or motors using hydrogen gas for cooling, high-purity copper grades are used.
The diameter, or gauge, of the winding wire affects two key factors. First, there is a direct correlation between the wire diameter and its ability to fill the coil slots, known as the fill factor. Second, the wire diameter influences the amount of current that can flow through the coil. Using a larger gauge wire increases the conductor area and reduces the need for insulation.
Increasing the diameter of the wire can make it stiffer, less flexible, and more challenging to handle. This stiffness can hinder the wire's ability to conform to the slot shape and affect the fill factor. While smaller gauge wires may seem more convenient and efficient, they require more insulation and result in a higher number of turns, which can increase the risk of wire damage during insertion.
Wires in the 22 to 24 AWG range offer a good balance between wire-to-insulation ratio, formability, and workability. In motor design, engineers consider factors such as slot opening, slot shape, winding configuration, and insertion method to ensure optimal performance.
Electroplated wires are employed in environments where conditions might cause deterioration or damage to the wiring. Common plating materials include gold, silver, and nickel, which are applied in various thicknesses and coated with insulation. Electroplating enhances the wires' durability and conductivity, providing better protection in harsh conditions.
Electric coils employ a range of insulation materials tailored to their temperature requirements. These materials include polyvinyl chloride (PVC), polyurethane, polyester, and various forms of polyimide. For applications reaching temperatures up to 250°C, polyimide is typically used. During winding, the wires are heated to ensure the insulation materials adhere properly.
Insulation materials play a crucial role in enhancing thermal resistance and protecting the wires. Their main function is to prevent short circuits by keeping wires from touching each other. Each insulation material has unique characteristics, including thermal capacity, gauge compatibility, and suitability for specific applications.
In certain applications, electrical coil wires are coated with two layers of insulation. This involves an initial undercoat followed by a topcoat. The double coating enhances the wire's strength and durability, combining the benefits of both types of insulation for improved performance.
Wires insulated with PVC offer resistance to oils, alkalis, acids, sunlight, weathering, and abrasion. PVC insulation operates effectively within a temperature range of -20°C to 60°C. Different types of PVC vary in pliability and electrical properties, catering to specific application needs.
Polyurethane is an insulation material known for its exceptional mechanical strength and high chemical resistance, making it suitable for harsh and hazardous environments. Its flexibility and adaptability make it ideal for outdoor applications. However, despite its robustness, polyurethane is not commonly used for electrical insulation.
Polyester insulation boasts a high temperature rating and low embrittlement factor, along with excellent abrasion resistance. It is noted for its superb windability, flexibility, and resistance to heat and solvents. Adding a polyamide overcoat to polyester enhances its windability and thermoplastic flow properties.
Polyimide is one of the most widely used forms of insulation for electromagnetic coils. It has excellent mechanical properties and is able to perform in high temperature applications. Polyimide is a polymer constructed from an imide monomer, which has two acyl groups bonded to nitrogen. The mechanical and thermal properties of polyimide have increased its use with electromagnetic coils since it can withstand a temperature that exceeds 240°C and is able to survive at high temperatures for 20,000 hours without experiencing any electrical breakdown.
The shape, design, and dimensions of a coil winding are crucial in determining its function and purpose. Factors influencing coil winding include inductance, quality factor, insulation strength, and the type of magnetic field needed. The winding structure is tailored to the coil's type and geometry.
Coil winding can be performed in several ways, with the basic forms being wild, helical, and orthocyclic. Each of these winding methods is executed using specialized winding machines.
Wild coil winding, also known as jumble winding, involves cross winding with uneven coil layers. This method is typically used in high-volume production settings. It is performed at very high speeds and is commonly used for relay coils, small transformers, and compact electrical motors, utilizing wire gauges as fine as 0.05 mm.
Helical windings, also known as screw or spiral windings, are characterized by their helical shape, resembling a corkscrew. This method is used for low voltage windings and can involve winding from a few strands up to over a hundred wires, arranged parallel to each other. The winding layers alternate direction, creating a pattern similar to a corkscrew, with variations in pitch angle as illustrated in the diagram below.
Orthocyclic winding is regarded as the most efficient method for coil winding. In this technique, each layer of winding precisely fits into the grooves of the layer beneath it, achieving a high fill factor of up to 70%. This design maximizes the creation of a strong magnetic field within a compact space. The winding pattern is continuous, with each turn parallel to the next and only a slight shift between layers.
Sandwich windings feature a distinctive arrangement where high-voltage and low-voltage windings are aligned along the same magnetic axis, with the high-voltage winding positioned between two low-voltage windings. This configuration minimizes leakage flux and is commonly used in transformer production. The design resembles a stack of discs.
In a bobbin coil, wire is wound around a bobbin, with variations depending on voltage, current levels, rating, and operating frequency. Bobbin coils are commonly employed in switch mode power supplies and power conversion units.
The quality, quantity, and winding pattern of a coil are determined by the coil winding machine. These sophisticated devices use CNC programming to precisely wind coils according to the specified requirements and ensure accurate results.
In the linear winding process, wire is wound onto a rotating coil body, component, or form. The wire is fed through a tube into the winding mechanism, which is controlled by a CNC program. This method allows for high-speed winding using three CNC axes.
In the flyer winding method, wire is fed from a roll attached to a flyer that rotates at a set distance from the coil. This technique is used for winding products that cannot be achieved through rotational winding. The coil remains stationary during the winding process, making flyer winding suitable for producing large coil products.
Needle winding is commonly used for producing stators and involves a fixed or oscillating needle with a vertical spindle to create winding patterns such as square track or elliptical. This method allows for higher fill factors and improved winding efficiency. Needle winding can be configured for multi-needle, open-core, or single-head operations, accommodating both inner and outer windings. The process can be tailored and engineered to meet specific winding requirements.
Toroidal winding involves wrapping a conducting wire uniformly around a circular ring, distributing it evenly across the circumference. This method offers benefits such as reduced core loss and high power density. Toroidal coils are particularly suited for low-frequency electrical applications. As the toroid rotates, it generates high-frequency effects, making toroidal coils both cost-effective and efficient.
The core of an electric coil is crucial for generating an electric field. While some coils use no core, others incorporate various core materials. The type of core material affects the strength of the magnetic field and the coil's inductance.
Amorphous cores are constructed from layers of magnetic tape, which minimize eddy currents and enable operation at higher temperatures. They are commonly used in high-efficiency transformers.
Iron cores generate strong magnetic flux and can maintain high magnetic fields. However, they can produce eddy currents, which generate heat at high frequencies.
Vitreous metals, characterized by their glassy and non-crystalline structure, are used in high-frequency transformers. Their low conductivity helps reduce eddy currents.
Ferrite ceramics, made from iron oxide and metallic elements, are designed to meet specific electrical needs. These ceramics act as insulators and help decrease eddy currents.
Laminated cores consist of thin iron sheets coated with insulation. This design prevents eddy currents from spreading outside the laminated layers, effectively reducing their impact.
Carbonyl iron cores are composed of powdered iron spheres coated with insulation. They are effective across various magnetic flux and temperature levels, minimizing eddy currents even at high temperatures.
Silicon steel features high electrical resistivity and excellent performance over time. It provides high flux density and is ideal for high-performance applications.
Molypermalloy is a powder core material made from a blend of molybdenum, nickel, and iron. It offers low core loss, minimal signal distortion, and good temperature stability, making it suitable for audio frequency applications, resonant circuits, and loading coils.
Sendust is a metal powder composed of iron, silicon, and aluminum, sintered into a core material. Known for its excellent magnetic permeability, low coercivity, and temperature stability, Sendust is used in abrasive applications such as magnetic recording heads.
Nanocrystalline material is a type of polycrystalline with crystallites measuring a few nanometers. It fills gaps between amorphous materials and is produced by rapidly cooling molten metal into a thin ribbon, followed by controlled annealing. With high resistivity and effectiveness at wide band frequencies, NC is ideal for compact components and complex EMI scenarios.
Electric coils feature a diverse range of core structures, each designed to meet specific performance and application requirements.
Pot: A pot core has a wall into which the coil is inserted and protected by the walls of the pot.
The choice of the type of electrical coil is determined by how it will be used, which includes whether the project requires a DC or AC electric motor. Electric coils, regardless of what type, have electric current that interacts with a magnetic field. Different types of coils are used for motors, generators, transformers, magnetics, and sensors Electronics, electricity, and magnetism use different forms of coils for each application. The list below is a brief description of various types of coils.
Electromagnetic wire is wound around a plastic core, commonly referred to as a "bobbin." These plastic cores are available in various sizes, and bobbin-wound coils can be impregnated, molded, or taped to suit a range of applications, including medical devices, sensors, relays, and automotive systems.
This type of coil is utilized when space is constrained and a bobbin or core cannot be accommodated. Positioned closer to the metal in the circuit, these coils offer enhanced magnetic capabilities. They are commonly employed in applications such as clutches, magnetic locks, and audio circuits.
A choke coil features low resistance and high inductance, making it suitable for both AC and DC currents. It is designed to block AC while allowing DC to pass through. The resistance of a choke coil increases with the frequency of the current.
Encapsulated coils, also known as molded coils, are safeguarded against moisture, corrosive chemicals, vibration, explosions, and harsh environmental conditions by being encased in a durable, temperature-resistant thermoplastic. This encapsulation enhances the coils' insulation and dielectric properties.
High voltage coils are designed for applications involving voltages that exceed safe thresholds, posing risks of sparks or electric shock. High voltage is typically classified as 1,000 volts for AC circuits and 1,500 volts for DC circuits. There are two main types of high voltage coils: ignition coils and Tesla coils.
A Tesla coil is a radio frequency oscillator that energizes a resonant transformer to convert high voltages to low voltages. It comprises two open electric circuits linked by a spark gap. For optimal performance, Tesla coils are constructed from copper wire.
Ignition Coils: Ignition coils are designed to convert lower voltage power into higher voltage to ignite a spark plug. Functioning similarly to an electric transformer, they feature both primary and secondary coil windings. Ignition coils are most commonly and recognizably used in the automotive industry.
Impregnated Coils: Impregnated coils have their winding voids filled with resin or other materials to stabilize the conductors. This impregnation seals the coil's structure, providing low viscosity, extended operational life, excellent dielectric strength, and the ability to function at very high temperatures.
A solenoid coil features a conductive core with a hollow center around which wire is wound. When current flows through the coil, it generates a magnetic field that creates magnetic potential, which is then converted into magnetic force for mechanical movement. In some cases, a metal core within the solenoid can actuate a hydraulic valve.
Tape-wrapped coils are designed for use in mild environments that do not contain chemicals or solvents. They are covered with sealing tape to protect against weather, dirt, and vibration. Tape-wrapped coils are a cost-effective option due to their lower price compared to other types.
Toroidal Coils: Toroidal coils are used in inductors and transformers. They are made by winding wire around a circular core with an open center. The toroidal shape allows for efficient magnetic field containment, minimizing leakage outside the coil. These coils are utilized in various industries, including transportation, audio, and power supply applications.
The function of a transformer coil is to adjust voltage levels between electrical circuits. Transformers can either increase or decrease voltage. They are passive devices that use electromagnetic induction to step voltage levels up or down between different circuits.
A voice coil consists of a bobbin, wire, collar, adhesives, and lead-out wire. The size of the bobbin is based on the diameter of the voice coil gap. This coil converts electrical signals into linear magnetic energy. Originally, voice coils were used to move the cone of a speaker, but their applications have since expanded to moving large masses at slow speeds. The interaction between the voice coil's magnetic field and the electric current is known as the Lorentz force.
An electric coil generates a magnetic field, which strengthens with an increase in the number of wire turns. The magnetic field's strength is directly proportional to the amount of current passing through the coil. As the current increases, the magnetic field's force grows stronger. When the current stops, the magnetic field disappears, a concept first demonstrated in the 19th century.
Every wire creates a magnetic field when current flows through it. By winding and looping the wires into coils, the strength of the magnetic field is enhanced, allowing it to store energy more effectively.
Coils are defined based on the frequency of the current they carry, including direct current (DC), audio frequency (AF), and radio frequency (RF). They are further classified by their functions, such as electromagnets, transformers, electric devices, or inductors.
The first electric coil was invented by Nikola Tesla, who is forever associated with this technology. The primary purpose of the coil is to achieve resonance, which occurs when current flows from a primary coil to a secondary coil.
In a circuit, electricity flows through a resistor and into an electric coil. Initially, the coil resists the flow of current to maintain stability. As the current increases, the coil allows more current to pass through. When the current is removed, the coil resists the change and continues to support the flow of electricity for a short time, even after the current has been disconnected.
The process of electricity flowing through a circuit happens very quickly and can be barely noticeable. Despite its simple function, an electric coil has a significant impact on the flow of electrical current.
The inductance of a coil depends on several key factors:
Inductance is measured in Henries (H), and its value is determined using a specific formula.
The fundamental structure of an electric coil consists of its conducting material, which can be categorized by its resistivity and conductivity. Resistivity, represented by the Greek letter rho (ρ), measures how strongly a material opposes the flow of electric current. Materials with low resistivity are better conductors, while those with high resistivity are poorer conductors. Conductivity, on the other hand, indicates how well a material can conduct electrical current and is calculated as the ratio of current density to the electric field within the material.
Silver is a highly conductive metal, with conductivity comparable to that of copper. However, it is less commonly used due to its higher cost, rarity, and susceptibility to oxidation, which can cause it to degrade rapidly.
Copper is the most widely used metal for electrical wires and coils due to its low electrical resistance and excellent conductivity. Its versatility allows it to be easily shaped into various coil forms, making it the preferred choice for most electrical applications.
Gold's ductility and malleability make it ideal for forming into wires and small electronic circuits. It resists corrosion and tarnish, which is advantageous for electronics. However, its high cost and limited availability make it less practical for widespread use.
Aluminum's low density helps reduce the weight of electrical coils, improving efficiency in moving parts and enhancing performance. It is particularly beneficial for applications like speaker wires and voice coils where weight reduction is advantageous.
Tungsten has an exceptionally high melting point, allowing it to emit light without burning up when heated. It maintains low vapor pressure at high temperatures and resists erosion, making it useful in high-temperature applications.
Carbon wire is cost-effective to produce and helps suppress radio frequency interference (RFI) and electromagnetic interference (EMI). It is commonly used in automotive applications and as a replacement for other types of wire.
Manganin, an alloy of copper, manganese, and nickel, is known for its minimal resistance change with temperature fluctuations. It is highly resistant to heat corrosion and offers long-term stability, also known as constantan.
Titanium's excellent mechanical and physical properties, including its resistance to acids, make it suitable for various industries. Its corrosion resistance makes it ideal for aerospace, chemical processing, and medical applications.
Nichrome is an alloy of nickel, chromium, and iron, known for its high resistivity and oxidation resistance. It is available in several grades, such as Nichrome 20, 30, 40, 60, 70, and 80, with operating temperatures ranging from 1050°C to 1180°C.
Kanthal is an iron-chromium-aluminum (FeCrAl) alloy used in high-temperature and resistance applications. It forms a protective alumina layer that acts as both a thermal conductor and an insulator, with an extremely high melting temperature of 1425°C.
Nickel wire heats quickly and has low resistance but melts at high temperatures. It is typically used in temperature-controlled applications due to its thermal properties.
Electric coils are crucial components in various electrical devices, such as motors, generators, transformers, and heating elements. Typically constructed from copper wire wound around a core, these coils depend on effective insulation to prevent electrical shorts and failures. Moisture ingress, or the penetration of moisture into the coil, poses a significant threat to this insulation. In this chapter, we will explore how moisture can enter electric coils and discuss strategies for preventing it.
Moisture can enter electric coils through several routes, including:
Moisture from the air can condense on the surface of coils and seep into the insulation, particularly in humid environments or when equipment operates below the dew point.
Rapid temperature changes can cause condensation to form on coils, especially when equipment is turned off and cools quickly.
External sources such as rain, flooding, or condensation from nearby equipment can lead to water entering the coils.
Poorly designed or damaged seals and covers can allow water to penetrate the coil.
Improper maintenance or storage can lead to contamination with dirt and debris, which can retain moisture and affect the coil.
Moisture can negatively impact electric coils in several ways:
Moisture can lower the insulation resistance of a coil, increasing the risk of electrical shorts and failures.
Moisture can cause corrosion or degradation of the coil’s metal components, reducing performance and shortening the coil’s lifespan.
Moisture heightens the risk of electrical shorts and failures, potentially leading to equipment damage or fire hazards.
To prevent moisture from infiltrating electric coils, consider the following measures:
Store coils in a dry, clean, and temperature-controlled environment. Handle them carefully to avoid damaging insulation or protective covers.
Desiccants can absorb moisture from the air in storage containers or equipment cabinets, helping to keep the environment dry.
Apply coatings and sealants to coil surfaces to create a barrier against moisture ingress.
Ensure equipment is designed with adequate ventilation and drainage to prevent moisture buildup.
Conduct regular inspections to check for moisture, dirt, or debris contamination. Address any damage or signs of moisture promptly.
Moisture ingress is a significant challenge for electric coils, and its effects can be severe. Implementing measures such as proper storage, the use of desiccants, protective coatings, improved ventilation, and regular maintenance can help prevent moisture-related issues. By taking these precautions, you can enhance the reliability and longevity of your electrical equipment.
An electromagnetic coil is an electrical coil that generates an electromagnetic field when electric current passes through it. The structure of an electromagnetic coil consists of a length of wire that...
Inductors are passive two terminal components of an electric or electronic circuit that are capable of storing energy in magnetic form. They oppose sudden changes in current and they are also called coils or chokes...
A solenoid coil is a common electrical component that uses a wire that is tightly wrapped around a core, usually made of metal, to generate an electromagnetic field. When an electrical current is passed through the coil, the electromagnetic field that is created provides energy for linear motion...
A voice coil is a winding of a wire, usually copper, aluminum, or copper-clad aluminum that is wrapped around a former (often called a bobbin) and then attached to the apex of a speaker cone...
Power supplies are electrical circuits and devices that are designed to convert mains power or electricity from any electric source to specific values of voltage and current for the target device...
An AC power cord is a detachable way of providing an alternating current of electric energy from a mains power supply to an electrical appliance or equipment. Serving industries like...
An AC power supply is a type of power supply used to supply alternating current (AC) power to a load. The power input may be in an AC or DC form. The power supplied from wall outlets (mains supply) and...
A DC DC power supply (also known as DC DC Converter) is a kind of DC power supply that uses DC voltage as input instead of AC/DC power supplies that rely on AC mains supply voltage as an input...
A DC power supply is a type of power supply that gives direct current (DC) voltage to power a device. Because DC power supply is commonly used on an engineer‘s or technician‘s bench for a ton of power tests...
Electric transformers are static electrical machines that transform electric power from one circuit to the other without changing the frequency. An electrical transformer can increase or decrease the voltage with...
Electrical plugs, commonly known as power plugs, are devices responsible for supplying and drawing current from a receptacle to the circuitry of an electrical appliance...
An electromagnetic interference or EMI Filter is an electrical device or circuit that filters specific unwanted frequencies in power lines or offending frequencies that are detrimental to a system. They receive AC or main power...
By definition a power supply is a device that is designed to supply electric power to an electrical load. An electrical load refers to an electrical device that uses up electric power. Such a device can be anything from...
An isolation transformer, just like typical transformers, is a non-moving device that transmits electrical energy from one circuit to another without requiring any physical contact. It works on the idea of magnetic...
A NEMA connector is a method for connecting electronic devices to power outlets. They can carry alternating current (AC) or direct current (DC). AC current is the typical current found in homes, offices, stores, or businesses...
A power cord is an electrical component used for connecting appliances to an electrical utility or power supply. It is made from an insulated electrical cable with one or both ends molded with connectors...
Power transformers are electrical instruments used in transmitting electrical power from one circuit to another without changing the frequency. They operate by the principle of electromagnetic induction. They are used in transmitting electrical power between...
A programmable power supply is a method for controlling output voltage using an analog or digitally controlled signal using a keypad or rotary switch from the front panel of the power supply...
An electrical transformer is a passive machine that transfers electrical energy from one circuit to another using a magnetic flux to induce an electromotive force. Transformers are used to increase (step-up) or decrease (step-down) voltages without changing the frequency of the electric current...
A toroidal transformer is a type of electrical transformer constructed with a torus or donut-shaped core. Its primary and secondary windings are wound across the entire surface of the torus core separated by an insulating material...
Electronically operated equipment depends on power transformers to convert electrical currents into voltage. Current transformers store and transport energy through power lines and grids...
Thomas Edison developed the power distribution system in 1882. He wrapped a copper rod in jute, a soft shiny fiber from plants, as an insulator. The jute wrapped copper rod was placed in a pipe with a bituminous compound...