An interesting thought, but the failures have happened on control boards
which typically do not need thermal relief because these caps aren't
connected to a plane. I'd be interested to understand how orientation of
the cap could cause a failure as it passes through the wave.  I'm still
trying to figure out the connection to failures on only a given few
boards when all 0.062" thick boards are run under the same wave solder
parameters and I'd guess that 99.9% or our boards use at least 1 if not
more of these Roederstein caps.  Definitely a conundrum.

-----Original Message-----
From: Kathy Kuhlow [mailto:[log in to unmask]]
Sent: Thursday, October 11, 2001 2:32 PM
To: [log in to unmask]
Subject: Re: [TN] failing capacitors


Are the capacitor locations properly thermal relieved?  What is the
orientation into the wave at this location?  Could it be that the part
is being thermally shocked due to lack of stress relief in the PCB or
orientation into the wave?

Kathy 

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