Need help with lumatek ballast :)

Hey everyone i have a question for anyone who either is using or have used the lumatek LK6240 ballast.
This is the one with the 4 settings -
400w, 400SL, 600w, 600SL.
Now i completely understand the super lumens side, but i cant figure out if this ballast can use 400w and 600w bulbs?
Obviously using the appropriate setting for each bulb, or is this the model that only uses 600w but dims to 400w?
Ive read online that theres 2 types, 1 can use both bulbs, the other cant and im hoping someone can shed some light on this for me.
 

Attachments

Top