The programmed start ballast is not what you would think (timer) it incorporates a starting method which is gentler on the lamp than either the rapid or instant start ballasts. It breaks the starting process down into programmed "steps" which increases bulb life
For frequent-start applications, rapid start ballasts are traditionally specified with the promise of minimal lamp life reduction compared to instant start ballasts.
Rapid start ballasts consume more energy than instant start, so there is a tradeoff in using them. Also, rapid start ballasts provide longer lamp life.
The wide variety of design methodologies of rapid start ballasts among manufacturers, can actually lead to a reduction in lamp life as compared to instant start ballasts
now are ya even more confused?
TEK brand lights use the newer
"triad" programmed start ballast, I recently got a "new in wrap" one on ebay for 39.00$
Josh, when i get home tonight Ill send you some good links to get you started in your quest for knowledge... plant lighting is one of my fav areas of study.
Regardless of format choice, you really should read the link that I posted in this thread, if you only read one page on the plant lighting, this one should be it... do your homework, there is a lot of wrong information floating around
http://terraforums.com/forums/showthread.php?t=111643
Butch