Question: how do hmi lights work?
Answer: HMI Lights. HMI (Hydrargyrum Medium-Arc Iodide) is a type of light which uses an arc lamp instead of an incandescent bulb to produce light. HMI lights are high-quality and correspondingly expensive. ... HMI lights require a ballast, an electronic (or magnetic) device which provides the ignition pulse and regulates the arc.