Quote Originally Posted by Dutch Pimp
my 400 watt magnetic ballast has a buzz upon start up...and full light takes 3-5 minutes....maybe more?...I never timed it.
Blimey, that's a long time. I presume that is normal? Mine has a slight hum and takes a couple seconds from the time of the contactor click to show some light and gets steadily lighter for about a minute, probably no more. I am embarrassed to admit I am not sure if mine is magnetic or not. I suspect not because I don't get those funny dark stripes when I take photos under it.

Also, for the sake of safety, it is best to run your lighting system through a contactor. It handles the massive power loads of the ballast and spares many a fried timer and ultimately fires and failures.