Same here Craig ; we're at same 40'C ambient ; 60'C inside of units ; and it
does weed out the split percentages you really do not want to chase in the
export fields .
Otherwise I concur with you ; I've had the same notions . We're class 2
medical ventilators .
We powercycle (ONLY) 8-12 hours with same ambient as well; I'd say yo're
right again stating the initial burn in does little for you, as you
virtually duplicate same on p/cycle .
Presuming you roll one shift on final assembly ; design it for overnight
(plug in evening ; test morning) even if you'd wish to be conservative and
cycle 12 hours ; that way your flow does not suffer to the extend of 15
hours ; which by the sound of it is causing you painful asynchronicity .
If you have enough units ; they generate their own heat in closed room .

See you

Paul Klasek
http://www.resmed.com

> ----------
> From:         Craig Patterson[SMTP:[log in to unmask]]
> Sent:         Wednesday, 13 January 1999 2:45
> To:   [log in to unmask]
> Subject:      [TN] Burn-IN
>
> As part of our stress screening for the electronic equipment that we build
> (consisting of standard SMD ICs, resistors, capacitors and a couple of
> Vacuum Florescent Displays) we burn-in the units at 104 Deg F. for 9 hours
> then power cycle the units (still at 104) for 6 hours, 4 minutes on, 4
> minutes off.
>
> I would be interested in any comments from the other Quality Professionals
> in the group as to the sensibility of this test screen. Are we wasting our
> time at these temperatures or would power cycling alone screen as much as
> does the soak and cycle at 104 Deg. F.
>
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