Sper Scientific 300037 Refractometer - Programmable - Manual (Page 4)

4
4. OPERATING INSTRUCTIONS
A. General Measurement
 To avoid damage, it is important to clean the
PRISM WINDOW
before and after each use.
 Press the ON/OFF button to turn the
Refractometer ON. The unit will automatically
shut off after about 3 minutes of inactivity.
 Perform the Calibration Procedure (4B)
 With the unit on, fill the PRISM WINDOW with
the sample to be measured and then close the
COVER
.
 Press the READ button immediately to ensure
accurate readings. Delays may cause the sample
to evaporate.
B. Calibration Procedure
 Clean the PRISM WINDOW before and after
each use.
 Fill the PRISM WINDOW with a standard solution
such as distilled or deionized water. The ideal
temperature of the solution and the unit should
be 65°~72°F (18°~22°C).
 Close the COVER.
 Press the ON/OFF button to turn the unit ON.
 Press the ZERO button for 3 seconds.
 When the procedure is complete, CAL will be
displayed.
 To check the nD value, press the ZERO button
once.
 This data can be viewed at any time to show the
last calibration value.
 A flashing crosshair symbol is displayed when
the calibration solution falls outside the accepted
range.
C. Zero Checking
 Fill the prism window with distilled water solution
that is at the same temperature as the solution to
be tested.
 Close the COVER