ATAGO NAR-2T User manual

Abbe Refractometer
Instruction Manual Cat.No.1220
1220-E28
PRODUCT REGISTRATION & WARRANTY CARD
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(1) Preparation of refractometer13
(2) Connection with circulating constant temperature bath15
Contents
1
Page
Precautions for use2
Refractive Index and Brix8
Unpacking and Setting-up9
Names and Functions of main parts
Power-on17
Calibration (Scale adjustment)
Finding average dispersion value and Abbe number37
Cleaning and maintenance42
Replacement of consumable supplies and component parts
(Simultaneous analysis of insoluble solids, sugar and water)
(1) Measuring glass, plastic samples25
(2) Measuring film samples28
(3) Measuring of double refraction samples30
Preparation for measurement
12.
13.
14.
6.
7.
1.
2.
3.
4.
5.
(1) Main unit of NAR-2T 10
(2) Digital thermometer12
(3) How to use Illuminator Selector Switch12
Measurement of liquid sample238.
(1) When measuring colored or cloudy sample35
(2) Discoloration or "Burning" of the main Prism35
(3) Measurement method of pasty sample35
(4) For measuring liquid sample containing insoluble solids36
Measurement of solid sample
9.
(1) Calibration with distilled water18
(2) Calibration with test piece20
Measurement of powdered sample3310.
Situations that may require additional attention
11.
Relation between Brix percent and Refractive Index (nD)49
Temperature correction table for sucrose solution50
Specifications 51
Repair and warranty52
ATAGO CO.,LTD. Service Center53
15.
16.
17.
18.
19.
(1) Prism 44
(2) LED lamp46
(3) Thermo-sensor unit47
(4) Desiccant48

Introduction
1. Precautions for use
For safe use --- Be sure to observe the following.
2
Explanation of indications
WARNING
CAUTION
Explanation of symbols
This symbol denotes an item which you are warned (or cautioned) of.
The contents of warning are described in detail in or near the ڹ.
This symbol denotes an action which you must not do (a prohibited item).
The contents of prohibition are described in detail in or near the ۑ.
This symbol denotes an action you must do.
The contents of instruction are described in detail in or near the ە.
Thank you for purchasing the "ATAGO, Abbe Refractometer NAR-2T". Before using your NAR-2T,
read this instruction manual carefully and understand how to use it. After reading this manual,
keep it on hand for future reference.
In this manual "For safe use" describes the important items necessary for safety. Read it
carefully.
This operation manual describes the items which you are required to observe in order to use
the NAR-2T safely to prevent injury to you and other people and damage to your property.
The explanation of the indications and symbols of those items are as follows. Understand them
first and then read the following pages to use your NAR-2T correctly.
If this indication is neglected and the instrument is handled
incorrectly, the user may be seriously injured and may result
in death.
If this indication is neglected and the instrument is handled
incorrectly, the user may be injured and the user's property
may be damaged.

Handling of this instrument
ە
ە
ە
ە
ە
3
WARNING
CAUTION
ە
When measuring a substance harmful to
the human body, be well aware of its
properties and put on protective gloves,
mask, etc.
If the instrument begins to smell
abnormally, overheat, or emit smoke, turn
off the power switch and disconnect the
power plug immediately.
Fire or malfunction may result if the
instrument is continued to be used.
Ask your ATA G O distributor for an inspection.
Do not attempt to repair, modify, or
disassemble the instrument yourself.
Improper servicing may result in fire,
electrical shock, or burns.
If the instrument is dropped or is subjected
to a strong shock, have it inspected by an
ATAGO distributor.
Fire or malfunction may result if the
instrument is used.
Do not apply water or sample over any part
other than the surface of the prism.
Application on any other part of the
instrument may result in a malfunction.
If this instrument is used to measure very
hot or highly acidic sample, the prism may
be damaged resulting in inaccurate
measurements.
1. Precautions for use

Handling of this instrument (Continued)
4
CAUTION
ە The prism is made of optical glass. Do
not tap or contact its surface with any
metal tool such as a spoon or
tweezers.
If the surface of the prism is damaged,
inaccurate measurements will occur.
ە After taking a measurement, completely
wipe off any sample on the surface of the
prism and surrounding area with tissue
paper soaked in water.
Then remove any remaining moisture
completely with dry tissue paper.
ە If you have measured a sample of
polymer or fats and oils, wipe it off with
tissue paper soaked in alcohol or
neutral detergent.
Then remove any remaining moisture
completely with dry tissue paper.
ە Always turn off the power switch after
use.
ە When transporting the instrument,
place it in its original box.
Carefully read this instruction manual and fully understand the function and operation of
each part of the instrument before use.
Check that each part of the instrument operates normally before use.
Check the necessary operations such as calibration according to the instruction manual.
The manufacturer shall not be held responsible for any or all damages as a result of use
of the instrument for those other than its intended purposes (measurement of Brix, Refractive
Index, Concentration).
The prism mounted on the sample stage that is in contact with a sample under measurement
is a consumable item.
Ensure that if use of the instrument has undesired effects on the consumption of the
measured materials, etc., ATAG O shall not be held responsible for the result.
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ە
ە
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1. Precautions for use

Handling of plug
5
WARNING
CAUTION
ەDon't plug the power cable into an outlet
other than AC100 to 240V.
Inserting the power plug in any other
outlet may result in shortcircuiting the
unit, smoking or fire.
ەDo not use the power cable if damaged
or broken.
If used, fire, electrical shock, or burns
may result.
For a new power cable, contact your
ATAGO distributor.
ەDo not insert or disconnect the power
plug with wet hands.
ەBe sure to hold and pull the plug when
disconnecting the power cable from the
outlet.
If the cable is pulled improperly, the plug
may be broken, and may result in fire or
electrical shock.
1. Precautions for use

Connection of circulating constant temperature bath
6
WARNING
ەFor connecting a circulating constant
temperature bath with the refractometer,
make sure to use the elicon tube (made
of vinyl chloride).
Moreover, tightly fasten each joint part
between the nozzle and tube with the
tie band.
ە The temperature of hot water to be
supplied from a circulating constant
temperature bath to this refractometer
is limited to 120Υ, and the flow rate of
the circulating constant temperature
bath should be 10 L/min. at maximum
through a nozzle of 6mm caliber.
To o much discharge not only increases
water pressure but also may cause
disconnection between the nozzle and
tube or may overload the water channel
inside the refractometer.
ە If the tube is damaged, replace it with
new one as immediately as possible.
If the damaged tube is continuously used,
the operator may scald himself with hot
circulating water.
ەPay careful attention to hot circulating
water.
1. Precautions for use

7
Items to be observed when using
1. Precautions for use
ە Do not drop the instrument or subject it to any strong shock.
ە The power cable may be damaged if mishandled in any of the following ways.
࣭Bending the cable.
࣭Pulling the cable.
࣭Twisting the cable.
࣭Placing the cable under heavy objects.
࣭Catching the cable between objects.
ە If the instrument becomes dirty, wipe it with a soft cloth.
ە Do not use benzine, paint thinner, etc. to clean the instrument.
Environmental conditions
Handling
Daily maintenance
ە Use the instrument at an altitude below 2,000m (above sea level).
ە Use the instrument indoors.
ە Use the instrument on a flat and level surface such as a desk or table.
ە Use the instrument where the temperature is between 5 to 40䉝.
ە Do not leave the instrument in a location exposed to direct sunlight or near a heating unit
where the temperature may rise.
ە Do not change the environmental temperature of the instrument suddenly.
ە Do not place the instrument in a place where it may be subject to strong vibrations.
ە Do not use the instrument where there is much dust.
ە Do not leave the instrument where the temperature is extremely low.
ە Do not leave the instrument in a damp place.
ە Do not place or drop heavy objects on the instrument.
ە Use the instrument under the condition where humidity is 80% at 31䉝or lower, falling linearly
to 50䠂at 40䉝.
ە Main supply voltage fluctuation should not to exceed 㼼10% the nominal voltage.
ە Installation categories (Overvoltage Categories): 䡈䡈
ە The pollution degree is 2 (according to IEC60664).

When light goes to medium Ȯthrough air with an
Refractive Index of air in the atmospheric pressure
assumed as 1, the ratio of the sine of incident angle
Șagainst the interface to the sine of refractive
angle șis called the Refractive Index of the medium.
Since the Refractive Index changes due to the
temperature, and wavelength of light, it is expressed
as follows:
1. What is a refractometer?
2. Refractive Index and Brix
8
If you put a straw into a glass of water, the straw appears bent. If the water contains
concentrations of sugar, the straw will appear more bent. This is called the "phenomenon of
light refraction". The refractometer applies this principle (if a solution has a higher concentration,
its Refractive Index rises proportionally). The refractometer is a measuring instrument devised
by Dr. Ernst Abbe in Germany in the early 20th century.
2. What is Refractive Index?
3. Brix scale
Note:
The scale of the NAR-2T is a Brix scale that is based on the Refractive Index of water
(nD=1.33299=Brix 0.0%). Brix means the scale of the weight (%) of sucrose (grams of
sucrose contained in 100 grams of sucrose solution). Thus, if a sucrose solution is
measured, it matches this concentration. However, almost all foods contain not only sugar,
but also a variety of dissolved components such as salt and protein. The total
concentration of these water-soluble materials is called the soluble solid content. When
this sample is measured, Brix is almost consistent with the soluble solid content (%) and is
used as a practical scale.
* The Brix scale is expressed in % mass (Sucrose) as the International System of Units
(SI unit).
For example, the Refractive Index of water at 20Υ
for the D line is expressed as ࠉ= 1.33299
(generally it is expressed in the form of nD=1.33299).
For relation between Brix percentage and refractive and Refractive Index (nD),
refer to page 49.
boundary
air
mediumȮ
Ș
ș
㹬 =1
㹬=
sin Ș
sin ș
n20
D
n
t
D
n : Represents the Refractive Index
t : Te m perature(Υ)
D : D- line of sodium
Note: The Refractive Index measured by setting the
Refractive Index of vacuum to 1 is called the
absolute Refractive Index, but it is generally
scarcely used.

●Abbe Refractometer NAR-2T (main unit) ………………………………1
●Digital thermometer………………………………………………………………1
●AC Power cable……………………………………………………………………1
●Lamp cable( LED lamp : 2) …………………………………………………1
● Test piece ………………………………………………………………………1
● Contact liquid (monobromonaphthalene)………………………………1
● Instruction manual (this book) …………………………………………………1
● Inspection certificate………………………………………………………1
3. Unpacking and Setting-up
9
1. Unpacking
2. Setting-up
a)
b)
Take all contents out of the packing case and check every item whether there is any damage
exteriorly or not.
Confirm the contents so that the following articles have been contained in the package
without lack.
a)
b)
c)
d)
Connect this refractometer to a mains outlet of AC100 to 240V, 50/60 Hz.
Set this refractometer in a place where it can be operated at an ambient temperature from
5 to 40℃.
Since this refractometer has extremely precise component parts inside, set it in an optimum
place where it is free from direct rays of the sun, strong vibration, dust, corrosive gas, heat
source.
Set this refractometer on a solid and level surface of a warkbench, etc. When setting, be
very careful not to give a strong shock to it.