Date: Mon, 14 Oct 1996 15:44:10 -0700 (PDT) From: "Rodney W. Grimes" <rgrimes@GndRsh.aac.dev.com> To: dbabler@Rigel.orionsys.com (Dave Babler) Cc: freebsd-hardware@freebsd.org Subject: Re: sticky drives (was: your mail) Message-ID: <199610142244.PAA14956@GndRsh.aac.dev.com> 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
> > > On Mon, 14 Oct 1996, Rodney W. Grimes wrote: > > > > This is extremely dangerous, BTW. When you take the drive out of the > > > freezer, condensation may form on the platters as the drive heats up. > > > Conversely, frost may form on the platters as the drive drops below freezing. > > > > 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? They are not hermetically sealed, they have a bidirection presure release and filter valve. Look very closely at your disk drives. If they did not do this (and the tried) the cases would blow apart when ship via unpressearized air freight at someplace close to 22K feet MSL. -- Rod Grimes rgrimes@gndrsh.aac.dev.com Accurate Automation, Inc. Reliable computers for FreeBSD
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199610142244.PAA14956>