400 watt system, 250watt bulbs

[beaglelax]

Can u run 250 watt on a unti that was designed to run 400 watt ???

[PaulErik]

The wattage of the bulb will depend on the ballast. In most cases if you have a 400-watt unit you can not operate 250-watt lamps safely. The ballast is used to limit current to the lamp. Using a 400-watt ballast on a 250-watt will cause the lamp to operate beyond specification limits (over drive the lamp with too mush power).