Measuring Concentration through Conductivity

Question:

How can I use conductivity to measure the concentration of a Solujet solution in order to control the concentration in a cleaning bath?

Answer:

In cleaning machines that have sumps or baths that are used repeatedly for cleaning where there will be dragout of solution on the parts being cleaned, evaporation of water, make-up water being added, and possibly dilution with rinse water, the cleaner concentration will constantly be changing as the solution is altered by any of these mechanisms. One way to control this is to monitor the conductivity of the solution which will allow you to determine the concentration of Solujet present which in turn will allow you to determine how much Solujet to add to bring the solution back up to full cleaning strength. For example the conductivity of Solujet at 22 deg C for weight/weight percent Solujet is as follows: 0.125% = 0.64 mS; 0.25% = 1.26 mS; 0.5% = 2.45 mS; 1% = 4.85 mS; 2% = 9.2 mS; and 4% = 17.9 mS. You can contact Alconox at cleaning@alconox.com to get a copy of an excel spreadsheet with this data in it along with a graph for interpreting results.