Additional Advice; Measuring Procedure; Cleaning And Maintenance - KERN ORA 20 BA Operating Instructions Manual

7.3 Additional advice

It is important that the samples being measured are representative samples. For
samples that evaporate easily, measurements should be carried out quickly. The
specimens should be at the same temperature as the measuring instrument in to
achieve an accurate result.
7.4

Measuring procedure

Make sure your hands are dry before handling the refractometer.
Open the prism cover [1] and use the supplied pipette [8] to apply a few drops
of the sample liquid [8] onto the prism surface [2], then close the prism cover
[1]. Spread the liquid evenly by pressing down on the prism cover [1].
Hold the device horizontally and wait about 30 seconds (for optimal tempera-
ture equalisation between the sample and device).
View the measurement scale through the eyepiece [4]. Point the prism surface
[2] of the refractometer at a bright light source while doing this.
Rotate the adjustment ring [5] on the eyepiece [4] to adjust the focus.
The boundary line will move on the measurement scale depending on the
concentration. This bright/dark boundary line shows the result on the scale.
If the temperature deviates from +20 °C, correct the measured result using the
corresponding value from the temperature correction table [13].
Carefully clean the supplied pipette [8] and the refractometer after carrying out
the measurement.
Important!
After every measurement, use a lint-free, absorbent cloth to remove the fluids from
the prism surface [2] and prism cover [1]. Then carefully clean the prism and prism
cover using a cloth moistened with water or if necessary alcohol, and dry both parts
using a soft, dry and lint-free cloth. Avoid rubbing the prism [2].

8 Cleaning and maintenance

Clean the refractometer using a soft, lint-free cloth moistened with water, or if neces-
sary alcohol. Do not use any aggressive or abrasive cleaning agents. Never immerse
9 ORA_10-20-32BA-BA-e-1510