K-Patents Process Refractometer PR-23-GP 

PR-23-GP Brochure (pdf)
Product Manual (pdf)
Instrument Verification (pdf)
Prism Wash with Steam (pdf)
Prism Wash with High Pressure Water (pdf)


K-Patents Process Refractometer PR-23-GP is an ideal all-round instrument for measuring the Refractive Index of water based hydraulic fluids and dissolving chemicals such as caustic soda. For underground and surface installations.

The PR-23-GP sensor is installed via a flange or clamp connection.

The measurement range covers 0-100 % by weight. The accuracy is typically ± 0.1 % b.w. and the measurement is automatically temperature compensated. Low and high concentration alarms can be configured. Because of the digital sensing technology, even large amounts of suspended solids, bubbles or color changes do not affect the measurement or the accuracy.

Key Features:

  • Universal calibration of each sensor: All sensors are freely interchangeable.
  • Full measurement range Refractive Index nD 1.3200 – 1.5300, which corresponds to 0-100 % by weight.
  • Completely digital system: particles and bubbles do not affect operation or accuracy.
  • Patented CORE-optics (US Patent No. US6067151): no drift, no re-calibration, no mechanical adjustments.
  • Ethernet connection and remote panel for data-logging and remote operation.
  • Process temperature range: -20°C – 150°C (-4°F – 300°F)
  • Fast process temperature measurement by built-in Pt1000 and automatic temperature compensation.
  • Dual connectivity: one transmitter can operate two sensors. A second sensor can be easily integrated later.
  • Easy on-site instrument verification within users' own quality assurance system with standard Refractive Index liquids.
  • Efficient water or steam wash for the prism: for cases where process residue fouls the sensor prism. Steam works when the liquid is particularly sticky or tenacious. In applications where steam may bake the process liquid onto the prism, pressurized water works to clean the prism.
  • ATEX approved for Zone II, area classification EX II 3 G EEx nA II T4.
  • ATEX approved for Zones 0 and 1, area classification ATEX II 1G Ex ia IIC T4 and for IM1 Exia I Ma (only Intrinsically safe PR-23-GP-IA with single sensor transmitter STR).
  • CSA certified for Class I, Div. 2, Groups A, B, C and D, T4.
  • FM approved for Class I, Div. 2, Groups A, B, C and D, T6.
  • cCSAus certified for Electrical Safety, Sensor: Class I, Pollution Deg. 3; Transmitter: Class I, Pollution Deg. 2; Installation Cat. II.