Re: gEDA-user: Parts Manager Working Document

[Bob Paddock <bob.paddock@xxxxxxxxx>]

On Tue, Jan 19, 2010 at 12:29 PM, Peter Clifton <pcjc2@xxxxxxxxx> wrote:
> On Tue, 2010-01-19 at 08:26 -0800, Edward Hennessy wrote:
>> On Jan 19, 2010, at 3:41 AM, Florian Teply wrote:
>> > Anything else to add??
>>
>> A few suggestions for additional parameters:

There gets to be fields needed like "Can a Substitute part be used?",
"Does this product require lot tracking"?, think FDA,
there will always be some obscure field to add...

Any parameters/category system is doomed to fail.
Been-there-done-that with a warehouse of several hundred thousand
parts.
Many you can't figure out what category they go in, or it does not
have a matching parameter so your biggest
group ends up being "Miscellaneous".  As someone else mentioned make
adding/removing (almost never happens)
fields easy.

> ESD sensitivity? (Yes / No, or some scale of handling susceptibility?)

All parts should be considered ESD sensitive, right down to the 1/2" metal bolt,
and the 100 pound 19" rack.  ESD protection should be part of the
manufacturing/design culture,
 not an individual part consideration.  There is a thread going on
right now on Time-Nuts about this very subject, it will
be of interest to most everyone here:

http://www.febo.com/pipermail/time-nuts/2010-January/044171.html

> ESD sensitivity? (Yes / No, or some scale of handling susceptibility?)

Moisture Sensitivity Level, MSL, is getting to be a problem with the
increasingly shrinking geometries of parts and packages,
and sometimes the MSL values can be darn right hard to find from manufactures.
It takes very little entrapped moisture to turn the smallest of parts
in to Pop-Corn when exposed to soldering temperatures.

> Light sensitivity (I can imagine some parts degrading under lighting -
> e.g. UV erasable EPROMS, ....)

All silicon based parts are light sensitive.   A few diodes even point
this out in their datas heets.
If you ever have a project that seems like it has a gremlin in, see if
the gremlin goes away when
it is dark.  Really fun to trouble shoot problems when the Sun only
comes through the window
at certain times of the day, until you make the connection.

> For example - would anyone bother entering the operating temperature
> range for a metal connector? (No plastic to melt).

I would.  For example NFPA regulations say that some of my products must work
at 500'F for five minutes.  Never-Say-Never...



-- 
http://www.wearablesmartsensors.com/
http://www.softwaresafety.net/
http://www.designer-iii.com/
http://www.unusualresearch.com/


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