From: Pearson Shane <Shane.Pearson@tafensw.edu.au>
Date: Thu, 19 Mar 1998 15:49:37 -0800 (PST)
To: "'StanSquncr'" <cypherpunks@toad.com
Subject: RE: UPSs
Message-ID: <ED111D55D096D111A1990000F8794AF506E274@itfexch3.isd.tafensw.EDU.AU>
MIME-Version: 1.0
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Hi Stan,

A simple low pass filter made of 2 large inductors and a
few high voltage capacitors will do the trick nicely.
Which is not a slow reacting device being passive.
Combine this with polyswitch style protection and some method
of discharging a really high voltage to ground and it'll be
even better.

A very cheap design that should be in all UPS's.
And is certainly a whole lot better than nothing at all
for removing harzardous spikes, etc.


> -----Original Message-----
> From:	StanSquncr [SMTP:StanSquncr@aol.com]
> Sent:	Thursday, March 19, 1998 4:59 PM
> To:	spectre@anthrax.net; cypherpunks@toad.com
> Subject:	Re: UPSs
> 
> In a message dated 98-03-18 23:54:33 EST, spectre@anthrax.net writes:
> 
> << ... Any decent ups will put the incoming power
>  through a "conditioner" that will filter out noise in the incoming
> power,
>  and rebuild the wave so that transient sags and spikes don't get
> through. ...
> >>
> 
> BUT, even the fastest electronics cannot respond fast enough to the
> initial
> spike, if that spike is too high in the first place (if your incoming
> power
> lines get hit by lightning, for instance), it's already too late.  My
> suggestion, don't trust a UPS to eliminate spikes, get it if you
> anticipate a
> need for back-up power to shut down your system in case of black-out
> (and
> screw the surge protectors, trust the filtering in your power supply
> to do
> that for you.)
> 
> Stan