What is Magnetic Ballast

Horace He

Last Updated: August 1, 2023

What is Magnetic Ballast

A magnetic ballast, also known as a choke, is an electrical power regulator used specifically in fluorescent light systems. It operates based on the principles of electromagnetism, where an electrical current passing through a wire generates a magnetic force around itself. The magnetic ballast consists of a coil of copper wire wound around a ferromagnetic core, similar to a transformer. This coil produces a magnetic field that helps regulate the amount of current that reaches the fluorescent light.

The primary function of a magnetic ballast is to ensure that the fluorescent bulb receives the appropriate voltage and current levels, preventing overheating and potential explosions. By trapping most of the current, the magnetic ballast allows only the right amount of current to flow through to the light. However, this variation in current flow can sometimes cause the light to flicker or produce a buzzing sound.

Magnetic ballasts are considered less advanced compared to electronic ballasts. Some magnetic ballasts require the use of a starter, a small cylinder-shaped component located behind the light fixture. The starter is filled with gas and, when heated, enables the fluorescent light to start. This starting method is known as the pre-heat method.