I have found that on Fulham’s website, you can find all of their ballasts and the lamps they claim they can power. They include the ballast factor (percent power for the tube), some of which are absolutely abysmal. For example, the WH2 ballast is listed on their website to be able to power an 18W quad CFL, but according to the sheet will only do so at 60% of the tubes power. Also, the WH3 ballast is listed on their website to be able to power an F17T8, but will do so at 148% of the tubes power. Well that is fine, since they actually tell you, but does anyone have the specs of these ballasts in terms of their characteristics? Are they constant-current, current-limited OCV, or maybe some combination of the two? I would love to know more about these because they don’t list every type of tube, and there could be other compatibilities that we don’t yet know about.

Thanks!

To my knowledge they are constant current sources

That is a start, I suppose when you tie two wires together you double the current. Anyone else have any more leads?

This may help
https://www.lighting-gallery.net/index.php?topic=5918.0

AFAIK, so far no one bothered to measure actual current set by this ballast or attempted to reverse engineer the schematics...