To produce a magnetic field, wire is wrapped multiple times around a core. Any straight wire can produce a weak magnetic field, but by wrapping wire multiple times around a core, the strength of the magnetic field is significantly improved. The wound wire and core are the main components of an electromagnetic coil. Read More…
Leading Manufacturers
Sag Harbor Industries, Inc.
Sag Harbor, NY | 800-724-5952We are proud of the craftsmanship of our engineers. All of our products are made right here in the United States and we promise that these items are created from high quality resources. Our electrical coils are unique and efficient.

Classic Coil Company
Bristol, CT | 800-825-4319Established in 1973, Classic Coil Company is a Contract Manufacturer of electronic coils. We manufacture coils for a variety of industries; winding wire gauges from 4-58 AWG. We are ISO 9001-2015 certified, ITAR registered and DFARS Compliant. Our Engineering services allow us to assist with design, reduce cost, and increase efficiency in production. Call or visit our website to learn more about our capabilities.

Quality Coils, Inc.
Bristol, CT | 860-584-0927We are an ISO 9001:2015 certified company which is internationally known for manufacturing high quality electromagnetic-coils. It is our goal to provide quality products, a commitment to speedy delivery, and competitive pricing. We understand that every application is unique, so we encourage you to contact us to discuss your specific requirements. Call us at 1-860-584-0927 and find out what our 50+ years of experience can do for you.

Torelco LLC
Alpha, NJ | 800-867-3526Since 1962, Torelco has been a supplier of electric coils and transformers of superior quality. We offer custom coils, solenoid coils, ferrite core coils & toroid wound coils to serve a range of industries. Markets served include medical, military, electronics, and industrial. When you work with us, our promise is to build to the exact specifications and meet the custom needs of our customers.

Precision Econowind, Inc.
North Fort Myers, FL | 239-997-3860Check out what’s new online at Precision Econowind, manufacturer of the highest quality custom coils at reasonable prices, with on time delivery. Serving the coil industry for over 30 years, we’re experienced with producing loudspeaker & medical industry coils, coils wound on customers’ bobbins/tooling; freestanding, flat wire, edge wound, square, rectangle & shaped coils. Submit your specs today!

Triad Magnetics
Perris, CA | 951-277-0757Triad Magnetics has been in the electric coils industry for over 75 years. Giving us the knowledge and expertise to be one of the best in the industry. We have a wide range of electric coils and inductors as well as the ability to custom engineer and manufacture electric coils to our customer’s needs. Having served the needs of many industries for more than half a century, Triad believes its experience makes the difference.

Johnson Electric Coil Company
Antigo, WI | 800-826-9741Johnson Electric Coil Company is a family owned manufacturer that specializes in custom transformers, coils and inductors. From three phase isolation transformers to single phase inductors and chokes, we carefully design our products to meet your exact specifications.

Electromagnetic coils, known as inductors, are a means for controlling the flow of electrical current by resistance. The main characteristic of electromagnetic coils is their need for consistency and maintaining the status quo. If the amount of current going through a circuit gets too high, it slows the flow. If it gets to low, it continues the current at a steady rate.
According to Oersted’s Law, when a current passes through a conductor, a magnetic field is produced, whose strength depends on the supply of current. The produced magnetic field is perpendicular to the conductor, which can be seen using Fleming’s right hand rule.
Fleming’s right hand rule states that if you curl your fingers around a conductor with your thumb pointing upward, your thumb will indicate the direction of the current, while your fingers show the direction of the magnetic current. The coil of an electromagnetic coil creates a magnetic field that cuts across the conductor and opposes the flow of current.
The resistance in an inductor increases as the supply frequency increases. This continues until it blocks the incoming current. In most cases, alternating current (AC) is blocked, while direct current (DC) is allowed to flow.
An inductor can serve as a filter to choke changes in current. They can block a wide range of high frequencies, while allowing DC current to pass through. In an amplifier, inductors isolate DC current from radio frequency (RF) signals.
Since electromagnetic coils can store energy for short periods of time, they are used in computers when power supplies are being changed. Inductors maintain energy as a magnetic field and retain the energy long enough for the change. This decreases the loss of power and allows for continuous flow.
Transformers are a form of inductor and have multiple windings of wire that are wound on top of each other. The conducting material in a coil is wire, which is its winding made up of individual loops. The loops or turns are prevented from touching by a nonconductive material to block current from passing between wires. In a transformer, the top wire or winding is the primary and receives current that it passes to the other windings termed secondary windings.