What is the purpose of a condenser fitted in a magneto?

The purpose of a condenser fitted in a magneto is to assist in the rapid collapse of the primary current and prevent arcing at the contact breaker points. When the current in the primary winding of the magneto is interrupted by the opening of the contact breaker, the magnetic field collapses quickly. This rapid change in current can create a high voltage spike, which can lead to arcing across the contact breaker points, damaging them.

The condenser, also known as a capacitor, absorbs some of the energy from this collapsing magnetic field. By doing so, it helps to smooth out the current change and provides a path for the energy that would otherwise cause a spike. This results in a more efficient operation of the magneto, producing a stronger spark at the ignition system while prolonging the life of the contact points.

Understanding this role of the condenser is crucial in recognizing how magnetos operate and why they are designed in this way within the ignition system of engines.