How efficient are mercury vapor ballasts? I would like to install a security light that has a bulb of 100W. It is a mercury vapor with a 120V ballast. It is a
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Types of Lamps in Illumination | Sodium vapour lamp | Mercury vapour lamp | Connections and testing - YouTube
![Sunlite 03679-SU MV400/DX/MOG H37 Mercury Vapor Lamp, 400 Watts, Mogul Base (E39), ED37, 12000 Hours Life, 22000 Lumen, Coated White Finish, 3600K - Amazon.com Sunlite 03679-SU MV400/DX/MOG H37 Mercury Vapor Lamp, 400 Watts, Mogul Base (E39), ED37, 12000 Hours Life, 22000 Lumen, Coated White Finish, 3600K - Amazon.com](https://m.media-amazon.com/images/I/617t17158mL.jpg)