• In-line Refractometers

In-line Refractometers

  • Refractive index (nD) : 1.32000 to 1.55700
  • Brix : 0.00 to 100.00%

The unit measures the refraction of light generated between the prism surface and a liquid sample.

The PRM-100α is upgraded from the PRM-85 in the following aspects:

  • Wider than ever 0.0 to 100.00% Brix range
  • Improved measurement accuracy: Brix ±0.05%, nD ±0.00010
  • Two options for setting the minimum indication decimal place
  • Simple two-piece construction: detection section and operation display section
  • Easy-to-read color display panel. Simply attach the unit to a piping system to monitor food or beverage production, pharmaceutical production, industrial fluid, washing devices, dilution/mixing devices, etc. Continuously monitor water content and mixing ratio with successive measurements of refractive index, Brix, or concentration.

*The prism is specially designed to prevent solid materials from collecting on the surface, even after extended periods of use.


  • Calibration with water
  • Digital display
  • AC outlet (AC100 to 240V)
  • Automatic Temperature Compensation
  • High temperature samples
  • Can be connected to a recorder
  • Alarm output for high- and low-limit values 
  • RS-232C Interface
  • In-line measurement 
  • User scales can be inputted 
  • Continuous measurement 
  • Refractive index scale



  • Brix of soft drinks
  • Concentration of beverage blending in the course of syrup and water
  • Concentration of liquid coffee extracts
  • Concentration of liquid condiments in the dilution blending & Internship
  • Fermentation level of alcoho
  • Concentration of sugar wastewater


  • Washing liquids - dilution coefficients, the water content, the concentration of contaminant liquids, and the concentration in the rinsing process
  • Concentration of cutting oil, lubricants, release agents or in process
  • Concentrations of IPA, DMF, and hydrogen peroxide solutions
  • Concentrations of coolants and brine
  • Polymer concentration Pendant polymerization
Model PRM-100α
Cat.No. 3574
Scale Refractive index
Measurement item One of Refractive Index (nD), Brix (temperature compensation according to sucrose solution), concentration (%) (temperature compensation according to samples), and temperature.
Measurement Range Refractive index (nD) : 1.32000 to 1.55700
Brix : 0.00 to 100.00%
Resolution Refractive index (nD) : 0.0001 or 0.00001
Brix : 0.1 or 0.01% (by selection)
Measurement Accuracy Refractive index : ±0.00010
Brix : ±0.05%
Temperature compensation range 5.0 to 100.0゚C
Wetted parts temperature resistance 5 to 150゚C
Light source LED (D-line approximation)
Materials in contact with the solution Prism : Sapphire, 
Prism stage : SUS316
O-ring : Kalrez ®
Display item Refractive Index, Brix, concentration, temperature(゚C).
High and low limit setting High and low control limits can be set with keys.
Output RS-232C, DC4 to 20mA
Output item Refractive Index (nD), Brix, concentration (%), temperature (゚C)
Display system Seven-segment LED
Alarm output Open-collector output for high- and low-limit settings (alarm output).
Cable Detection section - Display section (power supply 12V and RS-485)
Length: standard 15m (maximum up to 200m)
Power Supply AC 100 to 240V, 50 / 60Hz
International Protection Class Detection section IP67, Calculation Display section IP67
Included Accessories Detection section - display section connecting cable (Standard 15m)
Recorder output cable (4-20mA) (Standard 10m)
Clamp band (for use in mounting a sample inlet unit)
O-ring (for use in mounting a sample inlet unit)
Dimensions & Weight Detection section : 10.8 x 26.6 x 10.8cm, 3.3kg
Calculation Display section : 19.2 x 10 x 24cm, 3.3kg
Power consumption 30VA
Configuration environment 5 to 40゚C, 30 to 90%RH
Pressure resistance 0.98MPa (Detection section)