3. General information
GB
3.1 Intended use
KERN & Sohn GmbH
Ziegelei 1
D-72336 Balingen
E-Mail: [email protected]
Tel: +49-[0]7433- 9933-0
Fax: +49-[0]7433-9933149
Internet: www.kernsohn.com
The refractometer is a measuring instrument for determining the refractive index of
transparent substances in liquid or in some cases also in the solid state. It is used
to observe the behaviour of light as it passes from a prism with known properties
to the substance being tested.
Use of the refractometer for other purposes is contrary to its intended use and
may be hazardous. The manufacturer shall not be liable for any damages caused by
improper use.
Betriebsanleitung
Analoges Refraktometer
Operating manual
Analogue refractometer
KERN
KERN
ORA 80 BE Analog Expert
2-fach Skala Brix
ORA 80 BE Analogue Expert
2x Brix scale
Ziegelei 1
D-72336 Balingen
E-Mail: [email protected]
Version 1.3
KERN & Sohn GmbH
04/2025
Version 1.0
12/2014
Tel: +49- [0]7433-9933-0
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com
ORA_80BE-BA-d-1410
3.2 Warranty
The warranty shall be void in the event of:
▸▸ Failure to observe the instructions in the operating manual
▸▸ Use for purposes other than those described
▸▸ Modifications or opening the device housing
▸▸ Mechanical damage and/or damage resulting from media,
liquids, natural wear and tear
Contents
4. Basic safety information
1 Technical data..................................................................................................1
2 Description......................................................................................................2
3 General information........................................................................................3
3.1 Intended use....................................................................................................3
3.2 Warranty..........................................................................................................3
4 Basic safety information.................................................................................4
4.1 Follow the instructions in the operating manual...........................................4
4.2 Warning........................................................................................................4-5
5 Supplied items.................................................................................................5
6 Before the first use..........................................................................................6
7 Use/measurement..........................................................................................6
7.1 Zero point calibration.................................................................................. 7-8
7.2 Additional advice.............................................................................................9
7.3 Measuring procedure................................................................................ 9-10
8 Cleaning and maintenance........................................................................... 11
9 Storage.......................................................................................................... 11
10 Service.......................................................................................................... 11
11 Disposal........................................................................................................ 12
12 Additional information................................................................................. 12
13 Brix to refractive index (nD) conversion table............................................. 13
14 Annex............................................................................................................ 14
4.1 Follow the instructions in the operating manual
▸ Carefully read through the operating manual even if you have prior
experience with KERN refractometers.
▸ Every language version includes a non-authoritative translation.
The original German document is the definitive version.
4.2 Warning
▸ Do not let acids come into contact with skin or eyes. If acid comes into contact
with skin, flush with copious amounts of water. Shower if larger areas of skin are
affected.
▸ If acid comes into contact with eyes, keep the eyelid open and flush the eye with
running lukewarm water from the outer corner to the inner corner. Flush eyes for
at least 15 minutes. Then consult a doctor or ophthalmologist immediately.
▸ Thoroughly clean the refractometer after each use.
▸ The refractometer must not be exposed to extreme temperatures, high
mechanical stresses, strong direct sunlight or high humidity.
Models
KERN
Measuring
Scale
Dimensions
1 Technische Daten
Product
range and
graduations
Abmessungen
Nettogewicht
Mo
d e lle
Mes s bereic h
S kalen-­‐
Scales
Accuracy
Produkt
und
t eilung
K ERN
ORA 80BE
180x40x40mm
0,400kg
ORA
Brix: 0 -­‐5 0 %
0 ,5 % Brix
Brix:
% Brix
Brix: 5 0 -­‐
00,5
,5 % Brix
8 0 B E 0-50%
180x40x40mm
Brix: 50-80%8 0 %
0,5 % Brix
S kalen
▸ Make sure that you will not be hit by anything else while you are using the
refractometer, as this could cause serious eye injuries
Net weight
▸ The rubber eyeshade may cause irritation when in prolonged contact with the
skin. If this happens, consult your doctor.
Genauig keit
▸ Do not touch the lenses with your fingers.
0,400kg
Beispiel der Skala für den ORA 80 BE
5.Supplied items
Example scale on
ORA 80 BE
After unpacking and before using the device for the first time, check that all
listed parts have been supplied. Replace damaged or faulty parts immediately
and do not put them into operation.
▸ Refractometer
▸ Storage box
▸ Pipette
▸ Adjustment tool
▸ Cleaning cloth
▸ Calibration liquid (Distilled water)
Gerätebeschreibung
6
6
3
4
1
2. Description
2 Gerätebeschreibung
1
3
6
3
6
Prismenabdeckung
Prismenfläche
Optische Röhre mit Griff
Okular mit Einstellring des Diopters
Messbereich Verstellrad
Einstellschraube
1.
2.
3.
4.
5.
6.
9
Prismenabdeckung
Prismenfläche
8 Röhre mit Griff
Optische
Okular mit Einstellring des Diopters
Messbereich Verstellrad
10
Einstellschraube
4
5
11
9
7
12
8
7. Aufbewahrungsbox
8. Pipette
5
6. Before the first use
5
1
21.
2.
3.
4.
5.
6.
4
▸ This refractometer is not a toy. Keep out of reach of children.
1.Technische Daten
2
3
1.
2.
3.
4.
5.
6.
Prism cover
ORA_80BE-BA-d-1410
Prism
surface
Optical tubes with grip
Eyepiece with diopter adjustment ring
Adjusting wheel measuring range
Adjusting screw
Remove the protective film (if present) from the prism surface [2] and check that
the rubber eye-cup [4] is fitted correctly.
7. Use/measurement
The refractometer can be used to quickly and accurately determine the refractive
index of transparent substances, liquid or solid ones. To ensure correct measurement, the measuring device should be adjusted before measurements are carried
out. Please make sure your hands are dry before handling the measuring device.
The measuring instrument has two measuring ranges. To switch between the two
measuring ranges rotate the housing ring [5] between the eyepiece [4] and the
optical tube [3].
7. Storage box
8. Pipette
9. Refractometer
10. Calibration liquid
(Distilled water)
11. Adjustment tool
12. Cleaning cloth
!
2
The refractometer cannot be used for the measurement of oil-based fluids.
6
7.1 Zero point calibration
8. Cleaning and maintenance
▸▸ Hold up the refractometer against a sufficiently bright light source and look through
the eyepiece [4], holding the eyepiece closely against your eye/glasses.
▸▸ Rotate the eyepiece [4] to adjust it for your eyesight, until you can see the scale
sharply.
▸▸ Open the prism cover [1].
▸▸ Thoroughly clean the prism [2] and the underside of the prism cover [1] using a soft
cloth or soft paper (with alcohol if necessary) and wipe dry. Water should only ever
be applied to the measuring prism, not to other parts of the device.
▸▸ Now apply a few drops of the calibration liquid [10] onto the prism surface [2].
▸▸ close the prism cover [1]. The amount of fluid should be sufficient to moisten most of
the prism surface. There should not be any air bubbles between the measuring prism
[2] and prism cover [1].
▸▸ Wait about 30 seconds to allow the temperatures of the test fluid and prism to
equalise.
▸▸ Look through the eyepiece [4] while pointing the refractometer‘s prism surface [2] at
a bright light source.
▸▸ Through the eyepiece [4], you will see a bright and a blue field. The boundary line 7
between them shows the refractive index value on the scale which is also visible
through the eyepiece [4].
▸▸ With the aid of the supplied adjustment tool [11] to turn the adjustment screw [3]
at the side of the prism surface [2] the scale can be adjusted so that the
measuring device is optimally set up by moving the boundary line upwards or
downwards.
Calibration value: 0 % (Brix)
Clean the refractometer using a soft, lint-free cloth moistened with water, or if
necessary alcohol. Do not use any aggressive or abrasive cleaning agents. Never
immerse the device in water or hold it under running water. Never handle the device
with wet or damp hands.
Never touch the measuring prism [2] with hard tools made from plastic, wood,
rubber, metal, glass etc. Hard objects can quickly damage the relatively soft prism
glass, resulting in measurement errors.
The refractometer is maintenance-free.
Cleaning should be carried out immediately before and after each use of the
refractometer to maximise its life and optimise measurement results.
9.Storage
Store the refractometer in a dry, non-corrosive environment, preferably
between 10 °C and 30 °C.
10.Service
11. Disposal
The packaging consists of environmentally friendly materials which can be disposed
of via local recycling facilities.
The device and storage box should be disposed of by the operator in accordance
with applicable national or regional regulations at the place of use.
▸▸ For refractometers without automatic temperature compensation (ATC): Convert the
measured value to take account of the deviation in room and sample
temperature from +20 °C. (See the table at the end of this manual, Point 14.)
▸▸ Repeat step 4 (cleaning).
Important!
12. Additional information
!
The ambient/room temperature and the sample temperature influence
the refractometer measuring result.
The scales are designed for an ambient temperature of +20 °C!
If the measurements are carried out at a temperature other than +20
°C, the results must be correspondingly corrected.
A correction table can be found in the annex, Point 14.
The product may differ slightly from the illustrations.
Avoid exposing the refractometer to direct sunlight.
Never bring the refractometer into contact with solvents.
13. Brix to refractive index (nD) conversion table
1.43743 1.43967 1.37758 1.37936 28 29 59 1.43520 1.43299 1.37582 27 58 1.37406 26 57 1.37233 25 56 1.50129 1.50398 85 1.43080 1.49862 1.37060 24 55 84 1.42862 1.36889 23 54 1.49333 1.49597 82 81 83 1.42647 1.42432 1.42220 1.36720 22 53 1.36551 21 52 1.36384 20 51 1.4881 1.49071 80 1.42009 1.48552 1.36218 19 50 79 1.41799 1.48295 1.48040 1.36054 18 49 78 1.41592 1.47787 1.35891 17 48 76 77 1.41385 1.41181 1.35729 16 47 1.47535 1.35568 15 46 75 1.40978 1.47285 1.35408 14 45 74 1.40776 1.35250 13 44 1.47037 72 73 1.40576 1.40378 1.35093 12 43 1.34937 11 42 1.46303 1.46792 1.46546 70 71 1.40181 1.39986 1.34782 10 41 1.34629 9 40 1.46061 68 69 1.39792 1.39600 1.34476 8 39 1.34325 7 38 1.45348 1.45584 1.45822 67 1.39409 1.45113 1.34175 37 65 66 1.39220 1.39032 1.34026 6 35 1.44881 5 36 64 1.38846 1.33879 4 34 1.44650 62 63 1.38661 1.38478 1.33732 3 33 1.33586 2 32 nD 1.44193 60 61 1.38296 1.38115 1.33442 1 30 1.33299 0 31 Refractive index BRIX % nD Refractive index nD BRIX Refractive index 13
▸ The boundary line will move on the measurement scale depending on the concentration. This bright/dark boundary line shows the result directly 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.
% ▸ 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] and eliminate
any air bubbles present.
▸ Hold the device horizontally and wait about 30 seconds (for optimal temperature
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.
9
▸ Rotate the adjustment ring [5] on the eyepiece [4] to adjust the focus.
12
BRIX 7.3 Measuring procedure
13 Brix to refractive index (nD) conversion table
It is important that the samples being measured are representative samples. Measurements should be carried out quickly on samles that evaporate easily.If possible,
the samples should be at the same temperature as the measuring instrument in order
to achieve an accurate result.
% 7.2 Additional advice
1.44420 Data from „ICUMSA“ International Commission for Uniform Methods
of Sugar Analysis, at 20 °C and 589 nm wavelength.
8
14. Annex
Table 1: International Temperature Correction Table for °Brix (% sugar gradient)
14 Annex
Correct
the result
by the
following
values(%(refractometer
must be correctly
Table
1: International
Temperature
Correction
Table for °Brix
sugar gradient)
Correct
the result by
calibrated
atthe following
20 °C). values (refractometer must be correctly calibrated at 20 °C)
!
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 and dry both parts using a soft, dry and lint-free cloth. Avoid rubbing the
prism [2].
10
Temperature °C
Important!
11
After reading this operating manual, if you have any questions about setting up or
using the refractometer, or if any unexpected problem occurs, please contact your
dealer. The device housing may only be opened by trained service technicians
authorised by KERN.
10.0
11.0
12.0
13.0
14.0
15.0
16.0
17.0
18.0
19.0
20.0
21.0
22.0
23.0
24.0
25.0
26.0
27.0
28.0
29.0
30.0
% Brix
reading
0.0
5.0
10.0 15.0 20.0 25.0 30.0 35.0 40.0 45.0 50.0 55.0 60.0 65.0 70.0 75.0 80.0 85.0
-0.53
-0.56
-0.59
-0.62
-0.65
-0.67
-0.69
-0.71
-0.72
-0.73
-0.74
-0.75
-0.75
-0.75
-0.75
-0.75
-0.74
-0.73
-0.49
-0.52
-0.54
-0.57
-0.59
-0.61
-0.63
-0.64
-0.65
-0.66
-0.67
-0.68
-0.68
-0.68
-0.68
-0.67
-0.67
-0.66
-0.44
-0.47
-0.49
-0.51
-0.53
-0.55
-0.56
-0.57
-0.58
-0.59
-0.60
-0.60
-0.61
-0.61
-0.60
-0.60
-0.60
-0.59
-0.40
-0.41
-0.43
-0.45
-0.47
-0.48
-0.50
-0.51
-0.52
-0.52
-0.53
-0.53
-0.53
-0.53
-0.53
-0.53
-0.52
-0.52
-0.34
-0.36
-0.38
-0.39
-0.40
-0.42
-0.43
-0.44
-0.44
-0.45
-0.45
-0.46
-0.46
-0.46
-0.46
-0.45
-0.45
-0.44
-0.29
-0.31
-0.32
-0.33
-0.34
-0.35
-0.36
-0.37
-0.37
-0.38
-0.38
-0.38
-0.38
-0.38
-0.38
-0.38
-0.37
-0.37
-0.24
-0.25
-0.26
-0.27
-0.28
-0.28
-0.29
-0.30
-0.30
-0.30
-0.31
-0.31
-0.31
-0.31
-0.31
-0.30
-0.30
-0.30
-0.18
-0.19
-0.20
-0.20
-0.21
-0.21
-0.22
-0.22
-0.23
-0.23
-0.23
-0.23
-0.23
-0.23
-0.23
-0.23
-0.23
-0.22
-0.12
-0.13
-0.13
-0.14
-0.14
-0.14
-0.15
-0.15
-0.15
-0.15
-0.15
-0.15
-0.15
-0.15
-0.15
-0.15
-0.15
-0.15
-0.06
-0.06
-0.07
-0.07
-0.07
-0.07
-0.07
-0.08
-0.08
-0.08
-0.08
-0.08
-0.08
-0.08
-0.08
-0.08
-0.08
-0.07
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.00
0.06
0.07
0.07
0.07
0.07
0.07
0.08
0.08
0.08
0.08
0.08
0.08
0.08
0.08
0.08
0.08
0.08
0.07
0.13
0.14
0.14
0.14
0.15
0.15
0.15
0.15
0.16
0.16
0.16
0.16
0.16
0.16
0.15
0.15
0.15
0.15
0.20
0.21
0.21
0.22
0.22
0.23
0.23
0.23
0.23
0.24
0.24
0.24
0.24
0.23
0.23
0.23
0.23
0.22
0.27
0.28
0.29
0.29
0.30
0.30
0.31
0.31
0.31
0.32
0.32
0.32
0.32
0.31
0.31
0.31
0.30
0.30
0.34
0.35
0.36
0.37
0.38
0.38
0.39
0.39
0.40
0.40
0.40
0.40
0.40
0.39
0.39
0.39
0.38
0.37
0.42
0.43
0.44
0.45
0.46
0.46
0.47
0.47
0.48
0.48
0.48
0.48
0.48
0.47
0.47
0.46
0.46
0.46
0.50
0.51
0.52
0.53
0.54
0.55
0.55
0.56
0.56
0.56
0.56
0.56
0.56
0.55
0.55
0.54
0.53
0.52
0.58
0.59
0.60
0.61
0.62
0.63
0.64
0.64
0.64
0.65
0.65
0.64
0.64
0.64
0.63
0.62
0.61
0.60
0.66
0.67
0.68
0.69
0.70
0.71
0.72
0.73
0.73
0.73
0.73
0.73
0.72
0.72
0.71
0.70
0.69
0.68
0.74
0.75
0.77
0.78
0.79
0.80
0.81
0.81
0.81
0.82
0.81
0.81
0.81
0.80
0.79
0.78
0.77
0.75
ORA_80BE-BA-e-1510
14
">
