Century Grow Systems have created the Intelligent Sun Pro Ballast. Ballasts are required to regulate the power fed to the lamp and all High Intensity Discharge (HID) grow lights need a ballast.
The intelligent sun pro benefits from supplying a constant flow of 600 Watt power, dimmable from 400W-600W and having a built in timer! This means that you do not need to purchase any additional contactors or timers.
This product has short circuit protection, is extremely quiet and has a stable dual-fuse operation.