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  1. Real World Applications of Electromagnets

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    Motor coil

    As common as they are, electromagnetic devices are not as widely understood. An electromagnet uses an electrical current to generate a magnetic field. The strength of that field is directly proportional to the level of current supplied to the magnet, and the field’s polarity can be flipped by changing the direction of the electrical current. Electromagnets serve a variety of purposes in many day-to-day technologies, particularly in electromechanical and electronic devices.

    We’ll cover some of the most common uses of electromagnets in the world today, both in consumer products and for industrial applications, making many modern technologies possible.


    Real World Electromagnet Applications in Electronics

    Most people don’t directly see electromagnets in their daily life, but they are no less often used. Electromagnets are found in countless consumer and commercial products, including:

    • TVs
    • Audio Equipment
    • Computers
    • Cars
    • Elevators
    • Copy Machines
    • MRI/CT Scan Machines

    Real World Electromagnet Applications in Power Generation

    Generating power involves converting sources of primary energy into electric power. An electric generator stores mechanical energy in the form of electrical energy by using a wire coil in a magnetic field. This is done by rotating the coil, which induces a current, and industrial-scaled applications accomplish this with a large, rapidly spinning turbine to produce massive amounts of electrical current.

    This electrical energy can be stored and converted back into mechanical energy for a variety of purposes – such as running a motor. To do so, an electromagnet is supplied with a reverse current, creating a magnetic field that causes the magnet’s coil to spin, along with anything connected to it.

    Electromagnets make it possible to convert mechanical energy into electricity, and then back into mechanical energy. The electromagnetic device that converts these energies is called an actuator, which consists of a stationary and a moving component (such as a rotor), where the magnetic fields produce torque and force that can be harnessed. This same principle makes it possible to use an electromagnet’s induction coil to measure the magnetic field itself, making electromagnets capable of functioning as sensors.

    To summarize, electromagnets are used in four different ways in the power generation process:

    • Generators
    • Motors
    • Actuators
    • Sensors

    Real World Electromagnet Applications in Medicine

    Medical devices such as Magnetic Resonance Imaging machines (MRIs), use magnets thousands of times more powerful than your average kitchen magnet to generate signals in the radio-frequency range, which the device then measures and translates into images. This results in highly detailed pictures of bones, organs, and various tissues.

    Magnets are also applied in some cancer treatments, where a doctor injects magnetically sensitive fluid into the area around the tumor and uses a powerful magnet to generate heat in the body. The goal is to kill the cancer cells without harming the healthy tissues.

    These are just two common medical uses of magnets – others include:

    • Scanners
    • X-ray equipment
    • Dialysis machines
    • Disinfectant dispensers
    • Electromagnetic therapies

    Real World Electromagnet Applications in Aerospace

    Aerospace engineers have developed an almost entirely separate field of magnetics. Specialized uses involve sending finely controlled current and voltage to receiving systems to maintain altitude and other flight dynamics. In reverse, this also enables them to track the location and flight path of various aircraft and devices.

    Much of aerospace engineering would not be possible without electromagnetic technology. Electromagnets power many standard and specialized aerospace devices, such as:

    • Flight control covers for both commercial and combat aircraft
    • Missile programs
    • Aircraft loudspeakers
    • Traveling-wave tube (TWT) radar
    • Permanent Magnet (PM) generator rotor assemblies
    • Fuel pumps
    • Flow regulators
    • Cryogenic magnets suited for space environments
    • Magnetic holders for aircraft seats
    • Position-calibration and speed sensors
    • Air-compressor components
    • Motorized generators
    • Tachometer generators

    Electromagnets from Custom Coils

    Not many technologies are as ubiquitous to modern life while remaining largely hidden from direct experience as electromagnets. Just as electromagnetic devices have driven much of modern technology forward without being often credited as such, Custom Coils, Inc. has been quietly and dutifully driving the electromagnetic industry forward since 1978.

    With a highly customer-centric business model, our expert engineers work closely with every client to design and manufacture precision-engineered electromagnets for a wide variety of end uses. For any questions or to let us know about your electromagnetic needs, don’t hesitate to request a quote or contact us.

  2. Inductors vs. Electromagnets: Applications and Capabilities

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    Inductors and electromagnets are widely used components in electrical devices such as motors, generators, and transformers. While both components utilize a wire coil to establish a magnetic field, they each have functional differences that influence their suitability for a given application. Here, we highlight their similarities and differences while providing examples of how each is used in various electrical and electromechanical devices.

    What are Inductors and Electromagnets?


    An inductor is a two-terminal electrical component consisting of a wire wound into a coil. When electricity is applied to the coil, a magnetic field forms and gradually increases in strength. This magnetic field eventually collapses and is converted into electrical energy that is released back into the circuit.

    The ability of inductors to temporarily store energy in an electromagnetic field makes them useful for: 

    • Slowing current surges and spikes in circuits
    • Storing and delivering energy to a circuit
    • Impedance matching

    Inductors are categorized into the following types:

    • Coupled inductors featuring two coils connected by electromagnetic induction
    • Multi-layer inductors featuring a layered coil wrapped around a core
    • Ceramic core inductors featuring a dielectric ceramic core
    • Molded inductors created using plastic or ceramic housings


    Like inductors, electromagnets consist of a coiled wire through which electricity flows to produce a magnetic field. The strength of the magnetic field is proportional to the number of turns in the coil. To further increase the magnetic field’s strength, the coil is often wound around a ferromagnetic or iron core.

    In contrast to permanent magnets, the strength of an electromagnet’s magnetic field can be adjusted by modifying the amount of current flowing through the coil. The magnetic field can also be “turned off” by removing the electricity source from the magnet. This controllability makes electromagnets ideal for everything from powering electric doorbells to lifting and moving large pieces of metal.

    Electromagnets include three main types:

    • Resistive electromagnets featuring copper wires twisted around an iron core 
    • Superconducting electromagnets featuring cryogenically cooled coils of superconducting wire
    • Hybrid electromagnets featuring a combination of resistive and superconducting electromagnets

    Applications of Inductors and Electromagnets


    One of the most well-known uses of inductors is in induction motors, where they generate the magnetic field required to rotate the motor’s shaft. The speed of the shaft’s rotation is directly proportional to the frequency of the power supply. Other inductor applications include:

    • Filtering/blocking. In electrical circuits, inductors can filter, choke, or block higher-frequency alternating currents and smoothen output voltages.
    • Transformers and converters. Inductors transfer and store energy in transformers and power converters.
    • Tuning circuits. In tuning circuits, inductors allow a specific frequency to be selected.
    • Sensors. Contactless electronic proximity sensors utilize inductors in the head of the sensor to enable inductive sensing.
    • Ferrite beads. When used in ferrite beads, inductors help reduce electromagnetic interference in audio circuits.
    • Electromagnetic relays. Electromagnetic relays are automatic switches that use electromagnetic induction to open or close the switch during operation.


    The power and versatility of electromagnets make them an essential component of everything from small consumer electronics to mass-transit systems. In maglev trains, for example, electromagnets line the undercarriage of the train to levitate it above the guideway. Other applications of electromagnets include:

    • Motors and generators
    • Electric doorbells and buzzers
    • Magnetic locks
    • Headphones and speakers
    • Induction heating systems used in cooking and manufacturing equipment
    • Medical equipment such as MRIs and heart monitors
    • Magnetic recording technology and data storage devices such as hard disks and tape recorders
    • Laboratory research equipment such as mass spectrometers
    • Particle accelerators
    • Magnetic separation equipment
    • Industrial lifting equipment

    Custom Inductors and Electromagnets from Custom Coils

    Inductors and electromagnets provide essential functions in a range of electrical systems and electronic devices. At Custom Coils, we design and manufacture custom inductors and electromagnets according to specific field requirements and performance expectations. From high-quality materials to expert design recommendations, our in-house resources and experience allow us to create long-lasting products for nearly any electrical application.

    To learn more about our inductor and electromagnet design capabilities, please contact us today or request a quote.

  3. Types of Inductors

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    An inductor is one of the basic electrical components commonly used in electric circuits. Typically, an inductor consists of an electrical conductor wound into a coil, often including an iron core. The inductor stores energy in a magnetic field when current flows through it. This magnetic field induces an electromotive force (in the form of voltage) that opposes any change in current. are common in radio frequency systems, where they conduct currents and reduce feedback and interference. In circuits, inductors are crucial in controlling electrical flow.

    Custom Coils produces a wide range of inductors and can work with you throughout the product development life cycle to customize inductors for your application. As you review your options and specifications, consider the following types of inductors.


    Types of Inductors

    Inductors can follow multilayered, coupled, molded, ceramic, or other designs. Here are more details on the most common inductor types on the market.

    Air Core Conductor

    Air core conductors are hollow, which gives them low permeability and low inductance. They are most effective in high-frequency settings.

    Iron Core Conductor

    Also called ferrite core, these inductors have high resistance to electricity, high permeability, and low eddy current losses—all of which results in excellent performance in high-frequency applications.

    Toroidal Inductor

    These inductors are made of a donut-shaped iron core wrapped in wire. Thanks to its closed-loop, circular shape, toroidal inductors create strong magnetic fields.

    Laminated Core Inductor

    Laminated core inductors consist of thin steel sheets stacked to form the core. These stacks help block eddy currents and minimize energy loss.

    Powdered Iron Core Inductor

    These inductors are composed of magnetic iron material with air gaps. This construction allows the core to store more energy than other types of inductors. They also offer low eddy current and hysteresis losses.

    Axial Inductor

    An axial inductor is made by wrapping copper wire around a dumbbell-shaped ferrite core. A molding procedure then prints colored bands on it, and users can read these bands using a color code chart to determine the inductance value.

    Shielded Surface Mount Inductor

    The inductor wire wraps around a cylindrical bobbin and is secured in a specially made ferrite housing. These inductors are specifically created for PCB applications since the shielding minimizes EMI and noise from the inductor.

    Coupled Inductor

    These inductors feature two wires wound around a common core. The wires can be connected in various ways and transfer energy through mutual inductance. An example of a coupled inductor is a transformer.

    Multilayer Chip Inductor

    Multilayer inductors are made up of thin ferrite plates with coil patterns printed on them. The layered coils and insulation between them create high inductance.

    Shielded Variable Inductor

    With these inductors, a wire wraps around a hollow cylinder bobbin and can change inductance according to the core material placed inside. Ferrite cores increase inductance while brass cores decrease inductance.

    Molded Inductor

    Inductors with molded plastic or ceramic insulation are often found in circuit boards. They’re shaped as either bars or cylinders.

    Ceramic Core Inductor

    Ceramic cores are dielectric and cannot store much energy, but they do provide low distortion and heat loss.


    Inductor Applications

    The following are popular applications for each inductor.

    Air Core Conductor

    • RF tuning coils
    • Filter circuits
    • Snubber circuits
    • TV and radio receivers

    Iron Core Conductor

    • Transformers
    • High-frequency applications

    Toroidal Inductor

    • Medical devices
    • Industrial controllers
    • Switching regulators
    • AC circuits
    • Output filters

    Laminated Core Inductor

    • Electric vehicle onboard chargers
    • Noise and line filters
    • CH/CL filter chokes for signals
    • Transformers

    Powdered Iron Core Inductor

    • Transformers
    • DC inductors

    Axial Inductor

    • Line filters
    • Boost converters

    Shielded Surface Mount Inductor

    • Mobile and desktop devices
    • Servers
    • POL converters
    • Power supplies
    • Battery-powered gadgets
    • DC/DC converters in distributed power systems and field-programmable gate arrays

    Coupled Inductor

    • Cuk, flyback, and single-ended primary-inductor converters
    • Transformers

    Multilayer Chip Inductor

    • Bluetooth
    • Wireless LANs
    • Motherboards
    • Wearables
    • SBCs

    Shielded Variable Inductor

    • Automotive applications that comply with AEC-Q200 regulations

    Molded Inductor

    • Circuit boards

    Ceramic Core Inductor

    • High-frequency applications
    • Small-signal filtering
    • LC filter circuits


    Custom Inductors from Custom Coils

    Inductors are a type of device that transmits and measures current in relation to voltage. Inductors can be used in many types of applications, such as energy storage, filtering, and circuits. 

    Contact us to let us know how we can provide you with custom inductors or other coiled products. If you’d like to begin your project with us, request a quote today.

  4. What is a Solenoid?

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    copper solenoid

    A solenoid is a variety of electromagnet consisting of a copper wire coil wound tightly into a helix, an iron or steel housing, and a mobile plunger made of magnetic material. When an electric current passes through the coil, the solenoid produces a magnetic field and converts that magnetic energy into mechanical motion. Essentially, a solenoid converts electrical energy into mechanical work through electromagnetic forces. For example, solenoids are often used as a valve to actuate a push or pull force on a magnetic component in a device. Solenoids can also act as a switch in electromechanical devices. These electromagnetic devices are used in hundreds of everyday applications from doorbells to car ignition systems.

    Custom Coils designs and develops quality solenoids to meet the needs of your application. We work efficiently and expertly to create specialty coils for our valued customers.


    How Does a Solenoid Work?

    When an electric current is applied to a solenoid, it creates a powerful magnetic field that attracts or repels a magnetic material, ie magnetic plunger, to move inside of its housing. As the plunger moves back and forth, it creates the mechanical motion that powers the intended component.

    Solenoid magnets have an advantage over conventional permanent magnets because their magnetism can be switched on or off as needed by removing or applying the electrical current. You can adjust the strength of the magnetic pull by increasing or decreasing the electrical current.  Additionally, the direction of motion can be reversed based on the direction of current flow through the solenoid.

    There are two basic types of solenoids: valve and electric. In valve solenoids, a constant electric current is applied to the solenoid. Once activated, the piston or plunger retracts to open the valve that would otherwise block the flow of material. Once the electromagnetic field is broken, the solenoid is deactivated and the valve will close.

    Electric solenoids are used to close circuits to allow engines to run. When the solenoid receives the electric current it pulls nearby metal components in place to create a closed circuit. Constant electric current is required to keep the circuit closed and the engine running.


    Applications for Solenoids

    Without realizing it, you use solenoids every day. Solenoids vary in size and power, making them suitable for countless applications. Powerful solenoids consist of many coils, create strong magnetic fields, and can be used to power large machinery. A smaller, less powerful solenoid can be used for smaller functions like ringing a doorbell. Some of the more common applications for solenoids include:

    • Mechanical or fluid control valves
    • Starting a car
    • Ringing a doorbell
    • Door locking mechanisms
    • Nail guns
    • Air conditioning controls inside vehicles
    • Powering signal systems in the railroad industry

    While these simple but effective devices are used to actuate many common devices, they have become highly utilized in nontraditional physical motion applications, such Ion Beam Accelerator systems.

    There are innumerable applications for solenoids, as any device that requires force to create mechanical movement can benefit from their functionality.


    Custom Coils is Your Expert on Solenoid Design and Manufacturing

    Solenoids are important devices in much of the technology we use daily. These devices are effective, versatile, and easy to implement in your systems.  From conception to production, the experts at Custom Coils will partner with you to determine your specific needs and customize the right solenoid device for your application. Contact us to learn more about our services or request a quote today.