Would it be so severe in normal ambient cycle Werner ?
Even 90'C span over 24 hours seems (likely mistakenly?) pretty mild ?
I came across this as well ;
is there any average daily span ? in say average Alaskan warehouse ?
Could you elaborate a bit also on that 20'C cross line significance I noted
in the 785 standard ?
Could it be said storage forms equal part of the product life & warranty
considerations ?

Thanks ahead

Paul Klasek
http://www.resmed.com.

> ----------
> From:         Werner  Engelmaier[SMTP:[log in to unmask]]
> Sent:         Friday, 5 February 1999 7:47
> To:   [log in to unmask]
> Subject:      Re: [TN] Storage of assembled boards at - 50 degrees Celcius
>
> Hi Daan,
> Your problem is not storage at -50C, but storage from -50C going up to
> maybe
> +40C and back down again. That is a rather severe thermal cycle, which if
> repeated too often may cause failures, especially of solder joints.
>
> Werner Engelmaier
> Engelmaier Associates, L.C.
> Electronic Packaging, Interconnection and Reliability Consulting
> 7 Jasmine Run
> Ormond Beach, FL  32174  USA
> Phone: 904-437-8747, Fax: 904-437-8737
> E-mail: [log in to unmask]
>
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