[CentOS] Power-outage

Fri Jul 1 14:59:13 UTC 2011
Robert Heller <heller at deepsoft.com>

At Fri, 01 Jul 2011 16:25:33 +0200 CentOS mailing list <centos at centos.org> wrote:

> 
> Colin Coles wrote:
> > On Friday 01 July 2011 12:05, Timothy Murphy wrote:
> >>
> >> Any advice or suggestions gratefully received.
> >
> > If you are thinking of the UPS route a caveat: I have several HP servers and
> > most of them will not work on cheap UPS's as they do not produce the pure
> > sine wave modern HP machines require but rather a crude stepped voltage.
> 
> perhaps naively, I'm surprised: doesn't this mean they put crappy PSUs 
> in those servers?
> I thought decent PSUs were expected to deal with dirty input AC?

AND *I* thought *switching power supplies* (effectively) rectified the
AC input and then used the DC to drive a higher frequency system to get
the desired output voltages.  (The higher frequency means smaller, more
efficient transformers and need smaller filter caps -- all of which
means a lower cost, more reliable, more efficient power supply.)  Which
suggests that both the input voltage and frequency are not particularly
critical, so long as it does not have massive spikes/surges or
consistently low voltage. 

> _______________________________________________
> CentOS mailing list
> CentOS at centos.org
> http://lists.centos.org/mailman/listinfo/centos
> 
>                                                        

-- 
Robert Heller             -- 978-544-6933 / heller at deepsoft.com
Deepwoods Software        -- http://www.deepsoft.com/
()  ascii ribbon campaign -- against html e-mail
/\  www.asciiribbon.org   -- against proprietary attachments