Ballasts

Ballasts are used to start HID (High Intensity Discharge) bulbs, such as MH (Metal Halide) and HPS (High Pressure Sodium) bulbs. A ballasts allows the electricity to continue flowing through the bulb to keep the light on. The ballast's function is to control the electrical current running through the glass bulb so that there is just enough current flowing through so that the light ignites and is maintained, but not so much that the bulb is destroyed.

There are three different types of ballasts that are used with high intensity discharge lights:

• Magnetic Ballast - also called a core and coil ballast, which refers to the components inside the ballast. Along with a capacitor, they work together to control the current to ignite the light and keep the energy flowing at exactly the correct rate for the bulb. Magnetic Ballasts make humming sound where Electronic and Digital Ballasts are virtually silent.
  
  
• Electronic Ballast - use electronic circuitry to control the electrical flow within the HID bulb.
  
  
• Digital Ballast - works on a higher frequency, so it produces more light but uses less energy to do so. The digital aspect of the ballast allows it to function at consistently correct temperatures, which helps the bulbs to last longer.

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