An Induction Coil, also known as a Spark Coil, is a kind of disruptive discharge coil. It is an electrical instrument used to produce high-voltage pulses from a low-voltage DC supply.

Composition
An induction coil consists of two copper wire coils wound around a common iron core. The first coil, known as the primary, is made up of tens/hundreds of turns of coarse wire. The second coil, known as the secondary, is made up of many thousands of turns of fine wire. An electrical current is made to pass through the primary coil, thus creating a magnetic field. The primary coil acts as an inductor, storing energy in the magnetic field.

The interruption of the current leads to the collapse of the magnetic field. This lead to development of a high voltage pulse in the secondary terminals. This high secondary voltage is sufficient to cause an electrical discharge or spark.

Inductance of the coil is in direct proportion to the number of turns in it, it is also dependent on the radius of the coil and on the type of material around which the coil is wound.

Electrical Specifications to be Considered

• Inductance range
• Inductance tolerance
• Maximum DC resistance
• Operating current range

Use of Induction Coil

• Electrical Experiments
• Medical Therapy
• Physics Laboratory
• Radio