Skip site navigation (1)Skip section navigation (2)
Date:      Tue, 15 Oct 1996 13:49:14 +0930 (CST)
From:      Michael Smith <msmith@atrad.adelaide.edu.au>
To:        dbabler@Rigel.orionsys.com (Dave Babler)
Cc:        rgrimes@GndRsh.aac.dev.com, freebsd-hardware@freebsd.org
Subject:   Re: sticky drives (was: your mail)
Message-ID:  <199610150419.NAA18931@genesis.atrad.adelaide.edu.au>
In-Reply-To: <Pine.BSI.3.95.961014151833.18097A-100000@Rigel.orionsys.com> from "Dave Babler" at Oct 14, 96 03:34:48 pm

next in thread | previous in thread | raw e-mail | index | archive | help
Dave Babler stands accused of saying:
> > This is absolutely true, dropping a drive below 0 deg C is a sure fire
> > way to damage it.  Even the non-operating temp spec on almost all mfg's
> > disk is +5 C on the lower end.  Having done MIL-SPEC drive work that
> > had to operate over -55 to +125 C the actual hardest part of this range
> > was the -5 to +5 C range, condensation being a real killer.
> 
> Isn't the chamber where the platters reside hermetically sealed? If so,
> how would moisture be there to condense in the first place? 

Firstly; no, the chamber is often not sealed.  If you pull a drive
apart you will often notice that there's a breather port with a bit of
filter material stuck over it.  Many drives will have some silica gel
in them as well to help keep the humidity down.

Secondly, the drives are usually assembled in rooms with some nominal 
amount of air humidity, so that even if the unit were sealed, there would
still be moisture inside.

> -Dave

-- 
]] Mike Smith, Software Engineer        msmith@atrad.adelaide.edu.au    [[
]] Genesis Software                     genesis@atrad.adelaide.edu.au   [[
]] High-speed data acquisition and      (GSM mobile) 0411-222-496       [[
]] realtime instrument control          (ph/fax)  +61-8-267-3039        [[
]] Collector of old Unix hardware.      "Where are your PEZ?" The Tick  [[



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199610150419.NAA18931>