Supercharge, Magnetic Ballast, Metal Halide, 1000W
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A 1000 Watt Ballast suitable to run a 1000 Watt Metal Halide.
Ballasts are most commonly needed when an electrical circuit or device presents a negative resistance to the supply. If such a device were connected to a constant-voltage power supply, it would draw an ever-increasing amount of current until it was destroyed or caused the power supply to fail. To prevent this, the ballast will provide a positive resistance or reactance that limits the ultimate flow of current to an appropriate level.