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Single-phase inductances

E.F.C. is specialized in the design and manufacturing of inductances single-phaseand three-phase, electronic impedances and reactances, widely used in various sectors such as wind, photovoltaic, filtering, UPS and more.

In the electrical engineering field, inductance is a physical quantity known as "coefficient of self-induction", which measures the ability of an electrical circuit to interact with the flow of the magnetic field generated by the current passing through it.

In practice, single-phase inductors are composite inductive electromagnetic components by a winding (coil or solenoid) of conducting wire, made in air or wound on a magnetic sheet core. This nucleus can take different shapes, such as a mantle or toroidal one.


These inductive components are widely used as filters in direct current (such as filter inductances or chokes) and as current limiters in electrical circuits both single-phase and three-phase. They find application in power factor correction capacitor banks, electronic power supplies, rectifiers and electrical energy distribution systems.

Correct sizing and calculation depends on the specific application.

To find out more about our engine starting products or to request quotes and prices, do not hesitate to contact us. We offer our services in the province of Bologna and throughout the national territory.



Technical specifications

Main technical characteristics of single-phase inductances:

> Primary voltage: customer proposal
> Secondary voltage: customer proposal
> Frequency: 50-60 Hz
> Operating temperature: max 40 °C
> Protection degree: IP00 (open)
> Insulation class: F (155 °C)
> Insulation test voltage: max 5000 V

Three-phase inductors

Our design and manufacturing activity of inductive electromagnetic components it also extends to the creation of three-phase inductances. These components they are made of three windings (coils or solenoids) of conducting wire, made on a core of three-column EI magnetic sheet.

The creation of the magnetic part of the nucleus occurs by keeping the I's separate from the E's, and interposing a calculated air gap which is used to obtain the inductance value desired.


These inductive components are widely used in the industrial sector for various purposes applications. They are used as alternating current filters and as voltage limiters current in various electrical circuits. Among the main applications are batteries power factor correction capacitors, electronic power supplies, bridge circuits rectifier, electricity distribution systems and electrical systems industrial.

In particular, they are used as inrush current limiters during the starting of three-phase electric motors.



Inductance Specifications three-phase

Main technical characteristics of three-phase autotransformers:

> Primary tension: customer proposal
> Secondary tension: customer proposal
> Frequency: 50-60 Hz
> Operating temperature: max 40 °C
> Protection degree: IP00 (open)
> Insulation Class: F (155 °C)
> Insulation test voltage: max 5000 V

Made in compliance with the strict CEI 61558 and CEI 60076 regulations, the our inductances three-phase are designed to meet the highest quality and safety standards. We use high quality conductors, including copper and aluminum wires and strips, ensuring reliable and long-lasting performance.

Each three-phase inductance is designed and built to measure, taking into account of the specifications customer needs. Factors such as overall dimensions and mechanical layout, cooling systems, Electrical efficiencies and allowable loss levels are carefully considered during the design and manufacturing process. The final result is a product that guarantees optimal performance and long life.


In the practical context, the term "impedances" refers to components inductive electrical which are commonly made using coils wound in air or on a core magnetic. These impedances can be single-phase, two-phase or three-phaseand can be built on different types of magnetic cores or in air, based on specific needs technical or dimensional of the project.

Impedances are widely used in various industries, from electronics to electrical engineering, for a wide range of applications. These components are employed for the creation of current and voltage harmonic filtering systems, the rectified current smoothing, adapter circuits, resonant circuits and for limit the starting current.



In electrical engineering, reactances are considered imaginary components of impedances, resulting from the presence of inductors or capacitors in the circuits. These elements cause a phase shift between voltage and current. In practice, the term "reactance" comes often used as a synonym for inductive impedance.

Reactors are fundamental components present in a wide range of sectors, from electronics to electrical engineering, and are used for a variety of applications. Among these we include the creation of current harmonic filtering systems and voltage, rectified current smoothing, adapter circuits, circuits resonant, inrush current limitation and starting of electric motors.

EFC srl, based in Castenaso di Villanova (Bologna) and operating throughout the territory national, is ready to satisfy your needs by providing inductances, impedances and reactances tailoredfor your specific applications. Contact us for further information and for request a personalized quote.

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