Ed,
the water should be tested every week (if it is
large production). Particles, Becteria, (I believe there is a water test
spec. in the industry) etc. For applicaiton like the one you have,
you may have to install the filter system right before the cleaning
tank. UV may kill some, make sure you have no shadows... you still need to
get rid of the "dead body" bacteria, otherwise, you may end up some
"flowers"...
Good luck for Gardening using
PWB...
jk
Hi 'netters,
I have a client that is building extremely high
impedance low voltage assemblies (counting electrons from a photomultiplier
type circuit) that recently are failing test due to "leakage" They are
running water soluble flux with an SMT type aqueous cleaner fed by closed loop
D.I. water 1Meg/cm3 or better. Dynamic Ion testing shows very good results.
They ran a culture and found very high bacteria counts, well beyond fed
drinking water standards.Subsequent cleaning at the end user site (conditions
unknown at this time) seems to resolve the failures. I suggested UV
sterilization (not too expensive/risky) and also to verify "under soldermask"
cleanliness as well as "localized" contamination sites which "average" into
the overall assembly.
My question is if anyone has had any electrical
failures due to bacteria in the rinse water and what solution(s) were
successful. Any other suggestions or suspicions would be
appreciated.
Regards,
Ed Popielarski
QTA Machine
10 Mc Laren, Ste
D
Irvine, Ca. 92618
Phone:949-581-6601
Fax: 949-581-2448
Cel:
949-337-2578
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