Digital refractometers with automation


Refractometer-DR6300-TF with fully automatic sample supply-2022

Refractometer-DR6300-TF with fully automatic sample supply-2022

Key features
Key features

Maximum efficiency with automation

The DR6000-TF models with flow-through cell enable fully automatic operation in combination with drying unit, peristaltic pump and autosampler. There are four model variants available for the different requirements for accuracy, resolution and measuring range, whereby the same operation and functionality can be accessed.

  • For continuous measurements or series of measurements with high sample volumes
  • For low-viscous to slightly viscous samples
  • With highly accurate internal Peltier temperature control
  • Preinstalled and freely definable scales with conversions based on tables or formulas
  • Chemical-resistant materials such as measurement prism made of sapphire, measuring tray made of stainless steel
  • Also chemical resistant materials for the tubing and flow-through cell
  • Control with and without external software possible
  • Intuitive operation via state-of-the-art touchscreen display
  • Complete data recording and backup including audit trail
  • Flexible data export and simple data import with parameter processing via XML interface also possible
  • Flexible and method depending cleaning procedures adjustable
  • Compliance with global standards and norms

Please contact us, if besides the refractive index also other measured value verification (e.g. density, optical rotation, pH and conductance etc.) should to be determined in one step.


Typical applications

The DR6000-TF models are the ideal solution for manufacturers of flavors, fragrances and essential oils, as well as for the pharmaceutical and beverage industries.

  • Routine analysis with high sample throughput
  • Quality control of raw materials and auxiliary materials
  • Monitoring of the production of semi-finished products and end products
  • Quality and purity control of raw materials and end products
  • Determination of the sugar concentration in juices and alcohol-free beverages
  • Determination of the alcohol or extract content in beer, spices, wine or spirits

For a comprehensive overview of typical applications using the DR6000 Series of Digital Refractometers, visit our campus review Refractometer applications.


Conformity with national and international standards

Refractometers are also designed and used in accordance with standards. Standards in refractometry regulate, under the aspect of “best practice”, the environmental conditions and sample preparation as well as measurement tolerances, properties and equipment features of a device or certificates of calibration equipment and testing instruments. Whoever uses refractometers according to normative specifications can guarantee that measurements are correct and work according to reproducible procedures.

In order to make it easier for you to choose the right refractometer for your application, you will find for free download an overview of all standards and guidelines known to us in which refractometry is referred to.

Refractometer standards (PDF, 79 KB)

Any questions?
Get in contact with us, we will assist you in choosing the right refractometer for you.


All samples are measurable

From bright to dark, from basic to acidic, from a low to a high viscosity – for our refractometers almost all samples are measurable. A high-quality optics, intelligent evaluation logarithms and a powerful LED enable the measurement of particularly challenging samples. These include z. For example, non-homogeneous samples such as fruit juices containing pulp, opaque samples such as heavy oils or emulsions that are common in cosmetics. Aggressive acids and bases can be easily measured using a chemical-resistant stainless steel measuring tray and a sapphire prism.

In order to serve the existing variety of samples and the wide range of applications, we offer a wide range of different refractometers. For the selection of the suitable refractometer, it is helpful to define the required measuring range.

In the following table we have compiled an overview of typical samples from our customers and sorted them by refractive index. Most samples were measured at standard measurement conditions (20 ° C, λ = 589 nm), deviations are indicated. The measurements given are not specifications.

For your free download:
(All values have been compiled with best accuracy, but this information is supplied without liability.)

Refractometer samples (PDF, 189 KB)

Any questions?
Get in contact with us, we will assist you in choosing a suitable refractometer.

Model specifications

SCALESRefractive index (nD)
Concentration of sucrose, glucose, fructose and invert sugar [%Brix],
0–95 %Brix
nD 1.3200–1.7000
0–95 %Brix
nD 1.32000–1.58000
0–95 %Brix
nD 1.32000–1.70000
0–95 %Brix
±0.1 %Brix
nD ±0.00002
±0.02 %Brix
0.1 %Brix
nD 0.00001
0.01 %Brix
TEMPERATURE CONTROLWith integrated Peltier temperature control
(ICUMSA or freely definable)
TEMPERATURE MEASUREMENTWith integrated temperature sensor Pt100

Technical data refractometers (PDF, 140 KB)

New touch screen technology with 7.0 inch display

  • Operation via capacitive touchscreen with fast processing unit
  • The glass surface can be operated with gloves and cleaned with solvents
  • The 18-bit colour depth delivers 262,000 colours and produces clear images
  • Glare effects in sunlight are reduced to a minimum

Higher data security with better authorisation concepts

  • From now on with specific setting of network access restrictions
  • Enhanced authentication methods with Secure Login
  • The combination of user name & password protects saved data from unauthorised access
  • Audit trail to record configuration changes
  • Possibility of data reports with own logo

Fast, reliable measurement

  • Accuracy over a wide measurement range
  • Measurement of even turbid or highly viscous samples
  • Measurement with manual measurement time input or optimized measurement time thanks to automatic stability recognition
  • Multiple measurements with averaging
  • Recording of all measurement data as well as system and method settings in the manipulation-proof measurement data logger
  • Possibility of Statistical analysis

Unlimited number of methods

  • Measurement modes: single, continuous or interval measurements
  • Method parameters such as scales, temperature, temperature compensation, sample supply, limit values, comments
  • Alarm option for monitoring the limit values of standards and samples
  • Pre-defined scales such as %Brix sucrose, %Brix invert sugar, %Brix glucose, %Brix fructose
  • More than 100 additional scales available on request
  • Any number of freely definable scales with conversions based on tables or formulas such as m%, Vol.-%, g/cm³, °Oe, dry substance, salinity and %BRIX

Easy filling and cleaning

  • Small sample volume approx. 0.3 ml
  • Manual, semi-automatic or fully automatic sample supply
  • Chemical-resistant materials such as measurement prism made of sapphire, measuring tray made of stainless steel
  • Freely configurable cleaning processes (for devices with flow through functions)
  • Semi-automatic or fully automatic drying (optional)

Intelligent user administration

  • Can be activated or deactivated as required
  • Different authorisation levels can be set
  • Setup of user profiles is possible
  • Individual settings for specific users or work groups
  • For selection: Six languages (de,en,es,fr,it,pt)
  • Adjustment is menu-driven and easy to understand

Flexible data export

  • Print-out on serial ASCII printer (real paper)
  • Print-out on network printer in PDF or PS format
  • Print-out as PDF on USB flash drive or to network share
  • Export in HTML or CSV format on USB flash drive or to network share
  • Can be connected to a keyboard, mouse, barcode scanner or external PC
  • Easy integration into existing networks (DHCP-Client) or a LIMS

Compliance with global standards

  • Measurements according to reproducible procedures
  • Pharmacopoeias (USP, BP, JP, Ph. Eur.)
  • Secure Login regulates the reliability, integrity and availability of data uniquely and safely in accordance with 21-CFR Part 11

Sample supply options


Semi-automatic sample supply

  • The semi-automatic operation requires the DR6000-TF models with flow-through function, flow-through cell, drying unit DS7060 and a peristaltic pump DS7070, which draws the sample or the cleaning agent into the flow-through cell.
  • Thanks to the 3/2-way valve of the drying unit, you do not need to interchange the tubes when switching from the sample supply or the cleaning to the drying.

Fully automatic sample supply

  • The DR6000-TF models with through-flow function, flow-through cell, drying unit DS7060, peristaltic pump DS7070 and autosampler AS80 or AS90 allow for a fully automated operation.
  • The samples are taken from the vials of the autosampler and drawn into the flow-through cell by the pump.
  • If needed, the system can be automatically rinsed and dried after each measurement.


AS80 and AS90 - Laboratory automation for high sample volumes. You will find further information on our autosamplers such as an overview of possible applications, a selection of sample plates or accessories required on the product page of the autosampler.

Autosampler AS80 and AS90

Any Questions?

We will be glad to help.

A.KRÜSS Optronic GmbH
Alsterdorfer Str. 276-278
22297 Hamburg | Germany

Tel. +49 40 5143 17-0
Fax +49 40 5143 17-60