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To: OilView Users

Subject: OilView News #1, "Chemical Index repeatability"

This memo provided to share OilView information among OilView minilab users.

Today's subject: "Chemical Index repeatability"

You should expect to get Chemical Index repeatability within +/- 5% or +/- 2 ChemicalIndex units, whichever is greater. If you are having difficulty getting repeatability from theOilView Chemical index, here are some suggestions.

To begin with, it is important to understand that the Chemical Index is simply the dielectricdifference times 100. That is to say that if the dielectric for a used oil is 2.34 and thedielectric for the new oil is 2.26 then the chemical index is 0.08 x 100 = 8.

A change in dielectric less than 0.02 is not significant. A change in dielectric of 0.10 is veryserious. In other words a Chemical index less than 2 means that the new oil and used oilare indistinguishable, and a Chemical Index greater than 10 is very bad in most cases.Large Chemical Index (or large dielectric increase) is normally caused by oil degradation or

water contamination. Oil degradation, such as oil oxidation, normally results in very darkoil. Water contamination normally results in milky looking oil. You can verify watercontamination by 1) looking at the contaminant index, 2) use the shop microscope to viewwater droplets, or 3) crackle test on a hot plate.

Sometimes OilView users get a high Chemical Index and corresponding dielectric increaseand the oil doesn't look either dark in color or milky in appearance. There are two commonreasons for this. First is the possibility of wrong oil or wrong reference. You should getfamiliar with the dielectric values of all the new oils in your plant. Make a list of thedielectric values and put it on the wall behind your 5100. Use this like a fingerprint. Everyoil will have a dielectric that should repeat within +/- 0.02. Second is the possibility thattest was not done right. Use the "Verify" test to rule out this possibility.

Before you take an expensive maintenance action based on the OilView 5100, you should"Verify" that the test is valid. There are two ways to do this. The most direct way to"Verify" the Chemical Index is to do a "Short Test" on the reference oil. If everything is inorder, the Chemical Index for the reference oil should be

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Apply a few drops of the next oil and wipe dry with absorbent tissue. Repeat this step ifbig dielectric change such calibration.

Test next oil.

To understand more about dielectric and Chemical Index, copy one of the following intoyour Internet Explorer and say "go

http://www.compsys.com/drknow/aplpapr.nsf/38e828201e3b2af7852565a30053fd81/e6a75239e808a779852565a200646913?OpenDocumenthttp://www.compsys.com/drknow/aplpapr.nsf/38e828201e3b2af7852565a30053fd81/e6aada03698cae31852565a2006425c0?OpenDocumenthttp://www.compsys.com/drknow/aplpapr.nsf/38e828201e3b2af7852565a30053fd81/