Path: utzoo!attcan!uunet!aplcen!uakari.primate.wisc.edu!gem.mps.ohio-state.edu!tut.cis.ohio-state.edu!pt.cs.cmu.edu!sei!rsd
From: rsd@sei.cmu.edu (Richard S D'Ippolito)
Newsgroups: sci.electronics
Subject: Re: Fluorescent light ballasts
Keywords: advance
Message-ID: <4995@ae.sei.cmu.edu>
Date: 17 Nov 89 15:07:36 GMT
References: <22334@gryphon.COM>
Reply-To: rsd@sei.cmu.edu (Richard S D'Ippolito)
Organization: Software Engineering Institute, Pittsburgh, PA
Lines: 24

In article <22334@gryphon.COM> richard@gryphon.COM (Richard Sexton) writes:

=There are two kinds of ballasts: magnetic and elecronic. The
=former is by far the most common type, and is little more than
=a transformer. It is cheap to puchase. It has the drawbacks
=of being noisy (this is the source of the humm, or buzzing
=so often ascociated with fluorescent lights) and not
=terribly energt [sic]  efficient. A fixture with two 40 watt bulbs
=may actually draw 250 watts.

Twentyfive years ago, when I did lighting design, the typical transformer
ballasts for two 40W tubes consumed less than 20W, making the total fixture
demand less than 100W.  I know this because I also had to calculate the
air-conditioning load.

What are you talking about?!  Is this some hype from an electronic ballast
manufacturer?

Rich
-- 
When you can measure what you are speaking about, and express it in numbers,
you know something about it.
Lord Kelvin						      rsd@sei.cmu.edu
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