How Does Ignition Coil Works? Let's Discusse

Why does the ignition system have an ignition coil? what is its function and how does it work? We have written all the explanations below.

Ignition coil is one of the main components in the ignition system. The function of the coil is to change the battery voltage from 12 V to 25 KV.

Some people assume that ignition coil is only found in traditional ignition systems such as battery ignition systems or magneto ignition systems.

In fact, ignition coil can also be found on cars manufactured today. However, the igniton coil has changed a lot.

In the past, there was only one tubular coil that worked for all spark plugs. But now, there is a single coil or dual coil pack system where an engine does not only have one coil for all but one coil for each spark plugs.

What is the ignition coil function?

Its function is only to increase the ignition voltage.

Why does the ignition voltage have to be increased?

The reason is that in order to create a fire jump on the spark plug the battery voltage must be increased thousands of times. If the voltage is only 12 V then there will not be a stepping flame on the spark plug electrode, because to make electron jumps in an air gap, a large voltage is needed.

How does the ignition coil work?

To understand the working principle of an igniton coil, you need to study the igniton coil diagram below.

Main Ignition coil component

  • Primary winding
  • Secondary winding
  • Iron core

In general, ignition coil works the same as step up transformer. Step up transformer, using the electromagnetic induction method to increase the input voltage.

The way it works, there are two coils. Primary and secondary coils, primary coils are located inside while  the secondary coils located in outer side, so the magnetic field of the primary coils will hit the secondary coils.

If the number of turns of the secondary coil is less, the output voltage will decrease but if the number of turns of the secondary coil is higher then the output voltage will increase.

That is what happens during induction.

But on ignition coil, there is a little difference. In the ignition coil, the secondary coil is located inside the primary coil as illustrated above.

Then how does induction take place?

It turns out that the induction of the ignition coil does not occur when there is a current that passes through the igniton coil but it occur when the current in the ignition coil is cut off.

Primary coil will issue a magnetic field when electrified, this magnetic field will occur in the outer area due to the position of the primary coil in the outside area. When the electric current is cut off, the magnetic field that was previously formed will move very quickly towards the inside before finally disappearing.

The fast and simultaneous movement of the magnetic field will induce secondary coils with stronger results.

As a result, the secondary voltage has increased hundreds of times from 12 V to around 25 KV.

Then what is the function of the iron core in the ignition coil?

Its function is to pull the magnetic field from the primary coil, so that the movement of the magnetic field described above will be focused in very quickly.

The good conductor like iron, will be very effective to maximize the induction in the coil. Without this iron core, it is possible that the induction results could not reach 25 KV.