3. General information
GB
3.1 Intended use
The refractometer is a measuring instrument for determining the refractive index of
transparent substances in the liquid or 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.
KERN & Sohn GmbH
Ziegelei 1
D-72336 Balingen
E-Mail: [email protected]
Operating manual
Analogue refractometer
ORA 1 SA
ORA 3 SA
KERN & Sohn GmbH
Betriebsanleitung
Analoges Refraktometer
KERN
ORA 1 SB
ORA 2 SB
ORA 3 SB
Seawater salinity
NACL% Brix%
Salzgehalt
Meerwasser
NaCL%
NACL% Brix%
05 / 2025
Version 1.0
12/2014
Version 1.3
KERN
Tel: +49-[0]7433- 9933-0
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com
Tel: +49-[0]7433-9933-0
Fax: +49-[0]7433-9933-149
Internet: www.kern-sohn.com
Ziegelei 1
D-72336 Balingen
E-Mail: [email protected]
ORA_1SB_2SB_3SB-BA-d-1410
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
5Supplied 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
9Storage ......................................................................................................... 11
10Service ......................................................................................................... 12
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
1.Technical data
▸ Make sure that you will not be hit by anything else while you are using the
refractometer, as this could cause serious eye injuries
1 Technische Daten
Measuring range Scale graduaDimensions
Abmessungen
Nettogewicht
Mo d e lle
Mes s bereic h
S kalen-­‐
and Scales
Product
Produkt
undtions tAccuracy
eilu ng
K ERN
ORA 1 S B
S kalen
0 -­‐1 0 0 ‰
S alinit ät
1 ,0 0 0 -­‐
1 ,0 7 0 s g
0 -­‐2 8 % S alz
( NaC l)
0 -­‐2 8 % S alz
( NaC l)
0 -­‐3 2 % Brix
Genau ig keit
1 ‰ S alini-­‐
t ät
0 ,0 0 1
198x40x40mm
0-100‰ salinity
1,000-1,070 sg
1‰ salinity
0,001 sg
ORA 3SA
0-28% Salz
(NaCl)
ORA 3 S B
0-32% Brix
0,2%
(NaCl) 178x40x40mm178x40x40mm
0,145kg
0 ,2 % ( NaC l)
0,2%
0 ,2 % Brix
Brix
0 ,2 % ( NaC l)
198x40x40mm
178x40x40mm
▸ 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.
▸ The rubber eyeshade may cause irritation when in prolonged contact with the
skin. If this happens, consult your doctor.
Net weight
▸ Do not touch the lenses with your fingers.
0,155kg
0,145kg
0,145kg
5. supplied items
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.
Example scale on
ORA 2 SA
2 Gerätebeschreibung
4
1
2
2. Description
2 Gerätebeschreibung
3
3
4
6
2
1.
2.
3.
4.
5.
6.
Prismenabdeckung
Prismenfläche
Justierschraube
Okular mit Gummi-Augenmuschel
Einstellring des Diopters
6
Optische Röhre mit Gummigriff
1.
2.
3.
4.
5.
6.
Prismenabdeckung
Prismenfläche
8
Justierschraube
5
9
Okular mit Gummi-Augenmuschel
Einstellring des Diopters
Optische Röhre mit Gummigriff
10
11
9
12
8
7. Aufbewahrungsbox
8. Pipette
1.
2.
3.
4.
5.
6.
Prism cover
Prism surface
Adjustment screw
Eyepiece with rubber eyeshade
Diopter adjustment ring
Optical tubes with rubber grip
5
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.
7. Storage box
8. Pipette
9. Refractometer
10. Calibration liquid
(Distilled water)
11. Adjustment tool
12. Cleaning cloth
2
10
▸ Refractometer
▸ Storage box
▸ Pipette
▸ Adjustment tool
▸ Cleaning cloth
▸ Calibration liquid (Distilled water)
6. Before the first use
ORA_1SB_2SB_3SB-BA-d-1410
5
1
4
▸ This refractometer is not a toy. Keep out of reach of children.
Beispiel der Skala für den ORA 2 SB
3
3
▸ Carefully read through the operating manual even if you have prior
experience with KERN refractometers.
0,155kg
ORA 1SA
ORA 2 S B
7
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
Modell
KERN
1
3.2 Warranty
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 [5], holding the rubber eyeshade [4] closely against your eye/glasses.
▸ Rotate the eyepiece [5] 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.
▸ 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 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
between them shows the measured value on the scale which is also visible
through the eyepiece [4].
7
Clean the refractometer using a soft, lint-free cloth moistened with either 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
▸ Use the supplied adjustment tool [11] to turn the adjustment screw [3] behind
the prism surface [2] (under the rubber cap), and adjust the scale so that the
measuring device is optimally set up by moving the boundary line upwards or downwards.
Calibration value ORA 1SA: 0 ‰ (salinity) / 1,000 (sg)
Calibration value ORA 3SA: 0 % (NaCl) / 0 % (Brix)
▸ Repeat step 4 (cleaning).
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.
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.
!
The ambient/room temperature and the sample temperature influ-ence
the refractometer measuring result. The scales of the refractometer
models, which have "SB" in its name, 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. Refractometer models, which have "SA" in its name, are equipped with an automatic
temperature compensation (ATC). Between +10°C and +30°C measurement differences due to
temperature changes are automatically compensated.
12. Additional information
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
▸ The ORA 2SA and ORA 3SA instruments have a marking on the scale for the
liquid saturation point.
▸ If the temperature deviates from +20 °C and a refractometer without ATC is used,
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.
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].
1.50398 1.43967 1.37758 1.37936 28 29 59 1.37582 27 58 1.43743 85 1.43520 1.43299 1.43080 1.37406 26 57 1.37233 25 56 1.37060 55 1.49862 1.50129 84 1.42862 1.49597 24 54 83 82 1.42432 1.42647 53 52 1.36720 1.36889 23 1.36551 21 22 1.4881 1.49071 1.49333 81 1.42220 1.48552 1.36384 20 51 79 80 1.42009 1.41799 1.36218 19 50 1.48295 1.36054 18 49 78 1.41592 1.48040 1.35891 17 48 77 1.41385 1.47787 1.35729 16 47 76 1.41181 1.47535 1.35568 15 46 75 1.40978 1.47285 1.47037 1.35408 14 45 74 1.40776 1.46792 1.35250 13 44 72 71 73 1.40576 1.40378 1.40181 1.35093 12 43 1.34937 11 42 1.34782 10 41 1.46303 1.46546 70 1.39986 1.46061 1.34629 9 40 69 1.39792 1.45822 1.34476 8 39 68 1.39600 1.45584 1.45348 1.34325 7 38 67 1.39409 1.45113 1.34175 6 37 65 66 1.39220 1.39032 1.34026 5 36 1.33879 4 35 1.44881 63 64 1.38846 1.38661 1.33732 3 34 1.33586 2 33 1.44650 1.44420 61 62 1.38478 1.38296 1.33442 1 31 nD 1.33299 32 60 1.38115 % 0 30 Refractive index nD BRIX Refractive index 12
13
14. Annex
Table 1: International Temperature Correction Table for °Brix (% sugar gradient)
14Correct
Annex the result by the following values (refractometer must be correctly
Table 1: International Temperature Correction Table for °Brix (% sugar gradient)
adjusted at 20 °C).
Correct the result by the following values (refractometer must be correctly adjusted at 20 °C)
!
Temperature °C
Important!
BRIX Refractive index ▸ The boundary line will move on the measurement scale depending on the concen- 9
tration. This bright/dark boundary line shows the result on the scale.
% ▸ 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]. Close the prism cover [1]. Spread
the liquid evenly by pressing down on the prism cover [1] and elimi-nate any air
bubbles present.⇨
▸ 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.
BRIX 7.3 Measuring procedure
13 Brix to refractive index (nD) conversion table
It is important that the samples being measured are representative samples. For
samples that evaporate easily, measurements should be carried out quickly. The
samples should be at the same temperature as the measuring instrument in order
to achieve an accurate result.
nD 7.2 Additional advice
1.44193 Data from „ICUMSA“ International Commission for Uniform Methods
of Sugar Analysis, at 20 °C and 589 nm wavelength.
8
% Important!
11
10
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
-0.74
-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
-0.75
-0.73
14
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