Ionization tendency  Go To Index IPA  


    Device that extracts ions from residues of coating or flux agent on printed circuit boards etc by means of a circulated flushing liquid (75 % IPA, remainder: pure water) and measures the conductivity of the ion-containing solution to determine the ionic contamination of the plate. The flushing liquid itself is previously neutralized using an ion-exchange resin and is therefore made suitable for the extraction of small amounts of ionized substances. The procedure is illustrated in the figure. The resistance may reach a maximum of 10 9 Ωcm and is converted into a NaCl equivalency value with a microprocessor .

    If flux residues on the solder joint are exposed to high air humidity, the ions contained therein may become active and the surface insulation resistance (SIR) may decrease, resulting in errors on the component. Most often, the cause of such errors are impurities ionized by the moisture, invisible to the naked eye or concealed on the underside of the component. Just like Omegameter, Ionograph is a registered trademark of Alpha Metal.