M
mecramur
Should a low cost hand held refractometer be in a calibration program or simply zeroed at each use?
There's a third possibility; it should be in the calibration system and be zeroed prior to use.Should a low cost hand held refractometer be in a calibration program or simply zeroed at each use?
All, thank you for all the great information. I have been busy and just now checked the thread.
The refractometer is an inexpensive $130 hand held unit. It was purchased to check the concentratkion of water in oil used in a grinder. There is suppose to be 1 part DI water to 25 parts of oil. They are currently and have for some time been just mixng the fluid and not checking concetrations.
The instrument did not come with an RI for their specific chemistry but the tech did find a crosss reference chart for oil. The cross refernce syat the conctration of water is really 2% not 3.8%.
I questioned the cross reference accuracy and asked them to create a control sample, mixing 1cc of di water to 25 cc of cutting oil and then make several measurements with the new refractometer. This to me was a validation of the instrument and the readings and of the cross reference. This sample mixture could then be used to validate the instrument before each use.
What is the repeatability and accuracy of these hand held units?
Can these actually be calibrated or just verified?