Path: utzoo!attcan!uunet!mailrus!tut.cis.ohio-state.edu!ucbvax!hplabs!hp-pcd!hplsla!tomb
From: tomb@hplsla.HP.COM (Tom Bruhns)
Newsgroups: sci.electronics
Subject: Re: Fluorescent light ballasts
Message-ID: <5170060@hplsla.HP.COM>
Date: 20 Nov 89 20:46:06 GMT
References: <22334@gryphon.COM>
Organization: HP Lake Stevens, WA
Lines: 18

Gosh, with 6 quick responses to arrive here already, I was thinking
that this thread might provide me with some real information about
fluorescent ballasts and driving fluorescent tubes.  Does anyone
out there actually have some good library references?  In particular,
I'd like to know both theoretical and practical aspects.  What
designs have proven practical?  What sort of inverter designs do
people use to drive fluorescents from DC supplies (both low voltage
[5-15 volts] and moderate voltage [100-200 volts])?  How is the life
of a bulb affected by a DC component in the current?  What other 
factors affect bulb life?

BTW, I found the 250W a bit humorous.  I mean, 250-2*40 leaves
about 170 watts to dissipate in the ballast.  Considering the size 
of the ballast, ...  !   (Could Dick possibly have meant 250 VA?
I hope not; that's a pretty poor power factor!)

Tom Bruhns
tomb%hplsla@hplabs.hp.com