Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!isis!whester
From: whester@isis.cs.du.edu (William R. Hester)
Newsgroups: sci.electronics
Subject: Re: incandescent light bulb life extender
Message-ID: <1990Dec11.163848.21840@isis.cs.du.edu>
Date: 11 Dec 90 16:38:48 GMT
References: <5232@rsiatl.Dixie.Com> <4225@kitty.UUCP> <1990Dec7.142843.1870@rodan.acs.syr.edu>
Reply-To: whester@isis.UUCP (William R. Hester)
Organization: Math/CS, University of Denver
Lines: 22

I've found the best solution is to purchase incandescent bulbs rated for
130 VAC...these are industrial types not found in your grocery store.

When operated below rated voltage, the light output drops a bit, but the
operating life is extended to approx 260% of the hrs. at 130 volts.

The formula for operating indandescent lamps at other than rated voltage
is:
     %Life = (Rated Volts/Actual Volts)^(13.1)

As you can see, the life is very sensitive to the actual voltage used.

I'm not sure, however, how reduced voltage will affect the operation of
halogen cycle types...I guess it stops the tungsten replacement cycle and
actually reduces bulb life...???


-- 
Bill Hester, Ham Radio N0LAJ, Denver CO., USA | N0LAJ @ W0LJF.CO.USA.NA
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