What is Electromagnetic Ballast
An electromagnetic ballast is a device used in lighting fixtures, particularly in fluorescent lights. It operates on the principles of electromagnetism, where an electrical current passing through a wire generates a magnetic field. An electromagnetic ballast, also known as a magnetic ballast or choke, consists of a coil of copper wire. This coil produces a magnetic field that controls the flow of electrical current to the fluorescent light. The thickness and length of the copper wire determine the amount of current that passes through.
Electromagnetic ballasts can cause flickering or produce a buzzing sound. This is due to the fluctuation in current caused by the ballast. They are considered less advanced compared to electronic ballasts. Some models of electromagnetic ballasts require the use of a starter, a small cylinder-shaped component filled with gas, to initiate the light. This starting method is known as the pre-heat method.
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