FAQ for Digital Hand-Held "Pocket" Refractometer PAL-seris.
|• About the calibration.|
|• About the volume of the sample.|
|• About the measurement of a cold or hot sample.|
|• About the Maintenance.|
|• About the Brix (%) Scale.|
|About measurement value (PAL special scale).|
About the calibration.
For all models, zero sets by water.
About the volume of the sample.
Place approximately 0.3 ml of water onto the prism surface.
About the measurement of a cold or hot sample.
After dripping a cold or hot sample on the prism, wait 20 to 60 seconds before pressing the START/OFF switch so that the samples temperature and prism temperature approximate to each other. In such a case, stir the sample with a plastic spoon 3 or 4 times on the prism to shorten the time to equalize the temperatures of the sample and prism.
About the Maintenance.
• After measuring, use a lint-free tissue to wipe the sample off of the prism surface. If the sample contains oils or fat, use isopropyl alcohol and water to clean the prism surface.
About the Brix (%) Scale.
All Refractometers are designed to measure the refractive index of a solutoin. The Brix scale is based on a sucrose (sugar) and water solution. However, since most samples contain substances other than sugar - such as salts, minerals and protenis - the Brix percentage repesents the total concentration of all soluble solids in the sample. For certain samples, such as cutting oils and other industrial fluids, a conversion chart from the Brix percentage to the sample's total concentration may be necessary.
About measurement value （PAL special scale）.
Refractometers measure the concentration of all dissolved solids in a solution.
For example, the PAL-34S Ethyl Alcohol Refractometer can accurately measure the concentration of ethyl alcohol if the sample consists only of water and ethyl alcohol. Any other substance(s) dissolved in the sample will affect the readings. The refractometer cannot differentiate just the content of ethyl alcohol.
Likewise, the PAL-Citric Acid is designed to measure samples that contain only water and citric acid. It cannot analyze the concentration of other types of acid that may be present in the sample.