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Conductivity Meters for Electropolishing Bath?

I would like to measure the electrical conductivity of our electropolishing bath. However, most meters (preferably handheld) have plastic coatings which will degrade in acid, and are not valid at temperatures above 50 deg. C. Can anyone suggest a reasonably priced meter that would meet these requirements?

Joanna Mroz
1998

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There are several brands of conductivity meters that are used in the plating industry, and at least one (by Rosemount) use completely sealed torroidal probes. I'm not sure that this would work for you, but it is worth looking into. A Haring Cell is usedto determine solution conductivity for research purposes, but I have a hard time understanding why you would want to measure the conductivity in any real-time sense since there is so little that you can do to alter or control it anyway.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
1998

Joanna:

Conductivity measurements are a very convenient and quick way to control the purity of your rinse tanks and an indirect test for the strength of some, rather diluted, processing solutions (5-10% acid dips and such). However, when very concentrated baths are concerned, conductivity readings, in my experience, become of little value. Even specific gravity is a better quick and dirty test for such baths.

Good luck from Plater B

  
Craig Burkart
- Naperville, Illinois
1998

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We have found Great Lakes Instruments in Milwaukee to be a good supplier to work with. They have the torroidal probes that Ted mentioned. We have used them in a variety of baths and have only found that those baths with lots of nitric are a problem. The probes seem to be okay in phosphoric or sulfuric type baths. One good thing about their probes is that they do internal diagnostics totell you when they are about ready to fail.

Good Luck.

"PlaterB" Berl Stein
NiCoForm, Inc.

Rochester, New York

1998