but i dont know if you knew this or not some ballast did have multi light level on the ballast so you may have to cycle the switch few time to get it all light up

i know one Advance ballast do this way

hit the switch all 3 tube will be on then hit again switch to 2 or 1 tube set up and again back to all 3

sorta of 3 way light bulb work so just a thought

the other thing is that some lumiaire if you have " remote " type check the ballast for max distance if too far it may not fire up not very well at all

Merci , Marc

Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)