Thanks Mike, you are correct.
According to Flux designation we could have some residual of ions on PCB/PBA.
My experience was mainly by using Omegameter SMD-600 (automatic and dynamic ROSE)on samples to detect TIC (Total Ionic Contamination) after PBA wash off process. PBA soldered by Clean water soluble: Paste and Wave Fluxes .
TIC contamination level max 1,56 ug/cm2 NaCl equivalent as for ie. IPC-JSTD-001... or 0,5 ugr/cm2 in case of PBA coated by Conforma Coating IPC-AC-62A
Well, we had several contamination troubles due to Connectors (> 3,5 ugr/cm2 NaCl) or power components, or Raw PCB. Nothing with the solder process or fluxes. Ion Chromatography analysis was necessary to help understanding of contamination origin.
When occasionally we run TIC on a NC assembled PBA (Paste ROL0 or L1) after 10 minutes duration Test by Omegameter (IPA/DI water media at 45�C), even if TIC value was in the specs, the removed PBAs from Omegameter, have plenty of white residuals that in order to have a reasonable cosmetic aspect we used to deeply brush away the residuals from PBA. Other problem met, during and after test plenty of floating "stuff" in the media, requiring so often media filtration cycles with a risk to clog the filters(Mix Bed).
Our NC assembly Process (SMT and Wave) does not include TIC test after assembly.
In our processes, TIC test is a must as an SPC step, only for PBA soldered by Clean Process (WS Paste and WS flux).
To MASRI I do not have experience on PBA for TV products or similar. My suggestion could be, if you are really sure about your wave solder process is well set up, you should not worry but if you want to be sure and, if you have available an automatic tester (brands like above mentioned)or by mean of external Lab, try to run some TIC test on samples like a process validation.
After test results are in your hands you can decide how to proceed as a final solution for your process.
To have an automatic TIC tester on the floor and perform tests like you think once by hour it is a costly operation. So before to decide for it, do the right assessments.
Best Regards........GS
Sorry for my poor English.
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