Pradeep,

Another loaded question with an "it depends" answer.  During storage, the
boards are susceptible to heat and moisture which will degrade
solderability.  How well the PCBs are protected will increase the time for
the loss of solderability.  Old boards should have a solderability test
performed prior to usage to ensure they are still usable.  But that being
said, if the storage conditions are not extreme, and the PCBs are
solderable, then I would say they are OK to use.

Hope that helps.


Kevin Glidden
Manufacturing Engineer
Luminescent Systems Inc.

-----Original Message-----
From: TechNet [mailto:[log in to unmask]] On Behalf Of Pradeep
Sent: Friday, May 12, 2006 5:06 AM
To: [log in to unmask]
Subject: [TN] Storage
Importance: High

Is there any guideline with respect to the maximum duration of storage of
bare printed circuit boards before assembly. One of our customers takes the
PCB's in a single lot and use only a part qty immd. The balance boards are
used even after 1-2 years of manufacture. The boards are stored in a fairly
controlled conditions. Is there anything wrong in the part of the user in
doing so?


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Pradeep

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