Power cut if temps are too high

Owen DeLong owen at delong.com
Wed May 29 02:56:26 UTC 2019

It’s unlikely to apply to much of anything in a datacenter other than disks.

The reason it applies to disks is because rapid cooling of a drive will lead to uneven cooling of the platters which may cause abnormal stresses leading to shattering and/or warpage (depending on the material the drive platters are made from).

Most electronic components can tolerate a pretty steep thermal curve in either direction so long as the curve doesn’t take them out of spec one way or the other.

Also, most circuit boards and the like do not have enough mass to surface area ratio to lead to significant temperature differentials within a small physical distance.


> On May 28, 2019, at 12:18 , bzs at theworld.com wrote:
> Something to keep in mind is that some equipment, disks in particular,
> should only be cooled at a certain rate once they're hot, often
> annoyingly slow by the specs like 2-3 degrees C per hour but there are
> probably circuits sensitive to this also which could be anywhere.
> It came up because it happened to me in Cambridge, MA in the dead of
> winter and every helpful person in the building came by to suggest I
> just open windows and doors to the snowy outdoors to get things
> running sooner.
> It should be in the specs and if you're concerned about equipment
> running in too hot an environment you might be concerned about this
> also. Particularly after a forced power-down which also powers down
> equipment fans while the chips etc are still hot so will continue
> heating cases.
> Ambient air temperature might not be telling you the whole story is
> the point.
> I keep one of those big 5' fans, looks like something they use in
> Hollywood for windstorms and feels a bit like it on high, for just
> this sort of reason tho even if I just think it's getting warm, and
> several smaller fans to point at racks etc.
> The best thing you can do if it gets too hot is keep the air moving.
> (Where to plug the fans in after a power shutdown is your problem, I
> knew someone would think that!)
> -- 
>        -Barry Shein
> Software Tool & Die    | bzs at TheWorld.com             | http://www.TheWorld.com
> Purveyors to the Trade | Voice: +1 617-STD-WRLD       | 800-THE-WRLD
> The World: Since 1989  | A Public Information Utility | *oo*

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