400w Balast to power 250w bulb

[jason1985]

I´m sure the answer is no to my question but just wanted to double check.

I got an amazing deal on 2 400w MH ballast with 2 Lumenarc III Mini Mogul reflectors.

I only want to power 250w bulbs, can this be done with a 400w ballast or will it overpower the bulb causing it to burn out

 

[thincat]

The short answer is no:

Just please remember that a 400W ballast will run ONLY a 400W bulb, not a 250W bulb and vice versa a 250W ballast can ONLY light a 250W bulb.​

 

[jason1985]

okay! then I am left with either putting in two 400w bulbs or selling the two ballasts.

two 400w bulbs is overkill i think and cause too much heat under the hood

 

[thincat]

okay! then I am left with either putting in two 400w bulbs or selling the two ballasts.

two 400w bulbs is overkill i think and cause too much heat under the hood

agree. The total power generated by the ballast will never exceed 400W. You can run as many bulbs in parallel, but their total power absorbed should always be equal to 400W

400 bulbs = 1 watt / bulb

4 bulbs = 100 watts / bulb

1 bulb = 400 watts

Whatever number of bulbs you use, make sure to use the ones rated for the amount of wattage each will be supplied with to increase longevity of the bulbs. Dont expect a 200 watt bulb alone to last long with a ballast that supplies double the power. ie 400 watts.