The write-up details the design and construction of an Induction coil which was capable of producing a high voltage in the secondary winding so as to produce a spark between the adjustable terminals of the secondary winding. The manual method of winding a coil was used to produce the primary and the secondary coil. All other necessary connections were made with respect to the circuit diagram. When a current is applied to the device, a high voltage was induced in the secondary coil through electromagnetic induction in the primary coil. As a result of this high voltage induced in the secondary coil, an electric spark was produced between the terminals of the secondary coil. This valuable device can be applied in the radio transmission station, hospitals, automobiles, labouratories, etc.



A type of transformer that changes a low voltage direct current to a high voltage alternating current which produces an electric spark is known asINDUCTION COIL (Abbott, 1963).


When Michael Faraday and Joseph Henry independently discovered the electric induction and its principles back in 1831, they started a chain of events that led to the generation of alternating current electricity without which modern technology could not function. They built upon a discovery made by Hans Christian Oersted in 1820. Oersted found out that electric current flowing through a wire created a magnetic field. This was the first discovery linking electricity and magnet, and it galvanized scientists into a frenzy of research.

Faraday and Henry coupled with other few scientists followed the path of research and discovered that moving a magnet through a closed coil of winding did indeed “induce” the flow of an electric current in the wire. Initially, electric induction was a scientific curiosity, the direct current battery which had been invented by Allesandro Volta in 1800, had captured the interest of most of the researchers. It was until later in the 19th century that induction coils became of interest and that was due to the work of several individuals, such as French physists called Armand Hippolyte, Lious Fizeau and A. Apps who improved coil performance.

The induction coil uses the principle of electromagnetism. It is a corollary of Faraday’s law, together with Ampere’s law and Ohm’s law giving rise to the Lenz’s law. The EMF induced in an electric circuit always act in such a direction that the current it drives around the circuit opposes the change in magnetic flux which produces the EMF.

The induction coil does not only create an electric field or magnetic field, it also transforms the direct current which is usually of low voltage to high voltage. The induction coils were being used to create electrical discharges in gases at low pressure leading to the discovery of x-rays and real medical breakthroughs. It is often used in automotive ignition systems. Its principle is such that when a direct current is passed through the primary coil, a magnetic field is created which cause an EMF of a very high voltage to be induced in the secondary coil.  The high voltage causes a spark to be produced between the two terminals of the secondary winding.

Due to this spark produced across the gap between the two terminals of the secondary winding, the induction coil was also known as the SPARK COIL. The size of the induction coil is determined by the length of spark it could produce (Albert, 1998).


The study on the construction of an induction coil is significant in automobiles and linear engines. It is used in car ignition to produce a spark at the plug which is used to start car engines.

It is also seen in operation of some medical equipment. The induction coil produces a spark between the terminals of the secondary coil. This spark creates an electrical discharge in gases at low pressure which lead to the discovery of x-rays and in provision of real medical breakthrough (Breithaupt, (2000).


The principle aim of this project is to construct an induction coil, which is capable of inducing 2500volts on the secondary coil which would produce an electric spark at the adjustable gap between the two terminals of the secondary winding as a result of the very high voltage in it when a current is passed through the device.


The beginning of every task is always difficult. The fear of embarking on the project construction was a great challenge and a mantle of discouragement.

The material and all other components that was used in the construction was not common because the device itself is not common. As a result of this, sourcing for the materials and components was difficult. We had to visit different markets to get them complete.

The project is a great work and requires money to carry out the construction. Money has been scare and scarcity has been one of its characteristics. The scarcity of fund to finance the project was a big and challenging problem to overcome.

The unavailability of important books and the non easy access to the internet services made the search of information and knowledge needed for the project construction to be delayed. The challenge of moving outside the usual environment in search of information coupled with the waste of time and stress was quiet an intricate assignment.

In the packaging of the construction, we found it a bit difficult to source-out for the best and most suitable material for the packaging of the project work.


It is bulky because the winding was done manually.