AEG Refractometer RX 3 - Manual (Page 17)

17 GB
3 . repress the prism cover [1] . the liquid quantity
should be measured in such a way that most of
the prism surface is moistened .
4 . look through the ocular [4] and point the refrac-
tometer including its prism surface [2] towards a
bright light source if possible .
5 . looking through the ocular [4], you will see a
light and dark field . Its boundary lines indicate
the refractive index on the scale also visible in
the ocular [4] .
6 . By using the calibration tools [7], the scale can
be adjusted and the measuring device calibrated
by turning the calibration screw [3] behind the
prism surface [2] (underneath the rubber cap) .
the light-dark-border line must coincide with the
waterline . the room temperature should be at
+20 °c .
Caution!
the scales are set at an ambient air tem-
perature of +20 °c!
Measuring Process for Antifreeze
Protection-Check
1 . lift the prism cover [1] and apply a few drops of
cooling solution to be measured to the prism sur-
face [2] using the included pipette [10] . Distribute
the liquid evenly by pressing the prism cover [1] .
2 . close the prism cover [1] and look at the measu-
ring scale through the ocular [4] . Point the refrac-
tometer including its prism surface [2] towards a
bright light source if possible .
3 . turn the adjustment ring [5] on the ocular [4] to
set the focus of the vision .
4 . the border line on the measuring scale moves
depending on the anti-freeze agent concentra-
tion . this light-dark-border directly shows the
freezing point of the anti-freeze mix in °c on
the anti-freeze-scale [B] . the values show the
measured value for Propylene* (G13) and the
measured value for ethylene** (G11 / G12) . the
Propylene scale must also be used if you are not
familiar with the poured-in anti-freeze protection
or if it is a mixture of both . this is the only way
sufficient anti-freeze protection of the cooling