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From: uchuck@med.unc.edu (Charles Bennett)
Newsgroups: sci.electronics
Subject: Re: wanted: device to turn brownouts into blackouts
Keywords: brownout blackout
Message-ID: <3378@beguine.UUCP>
Date: 17 Apr 91 18:34:53 GMT
References: <1991Apr15.180755.19771@odin.corp.sgi.com> <11568@exodus.Eng.Sun.COM> <14257@ccncsu.ColoState.EDU>
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In article <14257@ccncsu.ColoState.EDU> bc338569@longs.LANCE.ColoState.Edu.UUCP (Brian Catlin) writes:
>In article <11568@exodus.Eng.Sun.COM> bender@oobleck.Eng.Sun.COM (I want to be eating rich soup in another town) writes:
>>
>>The question really is, why did the power company supply you with 60 VAC for
>>that long a period instead of just cutting off power completely?  I thought
>
>  I think an automatic cutoff
>  switch would work great for this.  If anybody has any good ideas about this
>  please post them!
>
>B. J. Catlin
>
>bc338569@longs.lance.colostate.edu

You people are probably too young to remember the "old self-latching
relay" trick.  Use DPDT or 3PDT relay, energize the relay via a pushbutton
switch, upon energizing one set of contacts takes the place of the switch
and holds the relay in.  If the voltage drops too low or has a momentary
drop out, the relay drops out and can only be restored via another push of
the pushbutton.

I am not adept a drawing in ascii, therefore I shan't try.

-- 
  Chuck Bennett                               INTERNET: uchuck@med.unc.edu
  Medical Sciences Teaching Labs              BITNET:   uchuck@unc
  CB# 7520  University of NC                  PHONE:    919-966-1134(w)
  Chapel Hill, NC  27599-7520