Vaisala K‑PATENTS® Sanitary Refractometer


Vaisala K‑PATENTS® Sanitary Refractometer PR-43-A


for in-line Brix and concentration measurement

The unique and innovative Vaisala K‑PATENTS® Sanitary refractometer PR-43-A system consists of a compact or probe refractometer and a graphical user interface. The refractometer is a stand-alone device capable of operating independently. It has a measurement range of 0 to 100 Brix and it provides an Ethernet or 4–20 mA output signal proportional to the temperature-compensated Brix value for real-time process control.

  • Sanitary compact refractometer PR-43-AC model for installation in pipeline sizes of 2.5 inch and smaller. The refractometer is installed in the pipe bend. It is angle mounted in the outer corner of the pipe bend directly or through a flow cell with a Sanitary clamp or a Varivent® connection.
  • Sanitary probe refractometer PR-43-AP for installation in large pipes, tanks, cookers, crystallizers and kettles and for higher temperatures up to 150°C (300 °F). The refractometer is installed in the pipe line or vessel through a 2.5 inch or 4 inch Sanitary clamp.
  • Sanitary flush mounted refractometer PR-23-APT for hygienic installations in cookers, cooling crystallizers and other vessels that have scrapers or mixers The refractometer is installed through an APV Tank bottom flange. It can also be installed through a steam jacket.

Different user interface options range from a rugged, multichannel, industrial computer to a compact lightweight and a web-based version, and allow the user to select the most preferred way to access and use the refractometer measurement and diagnostics data. The user interface of the refractometer can be installed locally in the field, remotely in the control room or in both locations by connecting several user interfaces in a network.

  • 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 Brix.
  • 3-A sanitary certified to meet the highest hygiene requirements of food production.
  • Withstands CIP and SIP processes and cleaning and rinsing of facilities.
  • Completely digital system: particles and bubbles do not affect operation or accuracy.
  • CORE-optics: no drift, no re-calibration, no mechanical adjustments.
  • PR-43-A Refractometer has a built-in web server with an instrument homepage. The homepage allows for configuring, monitoring, verifying and diagnosing the refractometer via an Ethernet connection.
  • Process temperature for compact model: -40°C…130°C (-40°F…266°F), for probe model: 40°C…150°C (-40°F…302°F).
  • Fast process temperature measurement by built-in Pt1000 and automatic temperature compensation.
  • Easy on-site instrument verification within users’ own quality assurance system and standard Refractive Index liquids.

Typical applications of K-Patents PR-43-A includes:

    Extraction, evaporation, brewing, distilling, sugar dissolving, blending, filling. Alcohol, rum, whiskey, brandy, vodka, molasses, liquors, cider and perry, alcoholic beverages, pre-mixed liquors. Beer and malt beverages, wort, cut beer, root beer. Juices, blended vegetable and fruit juices and nectars, still drinks, vegetable and juice concentrates, iced tea and coffee, instant coffee and tea. Soft drinks, energy and sport drinks, beverage base. Wines, grape must.
    Sugar coating. Sugar syrup.
    Sugar coating, topping, sugar dissolving, filling. Candies, jelly beans, caramel, chewing gum, flavors, syrup.
    Fermentation, extraction, evaporation, filtration, separation. Enzymes, yeast.
    Evaporation, spray drying. Condensed milk, skimmed milk, milk powder, casein, caseinate, yoghurt, ice cream, ice-cream mix, whey, whey cream, concentrated whey cream, whey  powder, lactose, lactose powder, infant formula, non-dairy creamer.
  • EGG
    Mixing, separation. Egg white, egg yolk, whole egg, mixes with added sugar or salt, egg powder, pasta with egg.
    Sugar coating. Donuts, sweet rolls.
    Mixing, evaporation. Citric acid, sodium benzoate, natural and artificial flavors.
    Extrusion. Synthetic sausage casings, polyamide, polyethylene, polypropylene, polyvinyl chloride, polyester, sodium hydroxide.
    Esterification. Plant ethanol ester.
    Salinity of brined products, frozen vegetables, fruits and seafood.
    Blending, cooking, evaporation. Preserves, canned fruits and vegetables, vegetable extract, sauces, instant soups, jam, jellies, marmalades, juice concentrate. Soy, soy milk. Tomato based products, tomato purée, pulp, paste, ketchup.
    Blending, cooking. Dairy desserts, rice-pudding, starch slurry.
    Sugar, syrup, honey, table-top sweeteners, inulin, steviol.
    Extraction, cooking, evaporation. Sodium chloride, salt substitutes, herbs, spices, seasonings, vinegar, soups and broths, sauces, yeast, protein, gelatin, agar-agar, soy drinks.
    Product to product interfaces, product to CIP interfaces, CIP fluids.
REFRACTOMETER PR-43-A ModelsPR-43-AC Compact model for small pipe lines; PR-43-AP Probe model for large pipe lines and vessels.
Refractive Index rangeFull range, nD = 1.3200…1.5300 corresponds to hot water…100 Brix or % by weight.nD = 1.2600…1.4700.
AccuracyAcross the full range of 0−100 Brix:
Refractive index nD ±0.0002 corresponds typically to ±0.1
Brix or % by weight.
High accuracy version -HAC in the range of 0−30 Brix and 4−30°C:
±0.05 Brix or % by weight.
±0.02 Brix or % by weight (in set-point applications).
RepeatabilityAcross the full range of 0−100 Brix: nD ±0.00004 (corresponds typically to ± 0.02 Brix or % by weight).
Speed of response1 s undamped, damping time selectable up to 5 min.
CalibrationWith NIST traceable Cargille standard R.I. liquids over full range.
Patented CORE-OpticsNo mechanical adjustments and digital measurement with 3648 pixel CCD element, sodium D-line light emitting diode (LED), built-in Pt-1000 temperature sensor (linearization according to IEC 751).
Temperature compensationAutomatic, digital compensation.
Instrument verificationWith NIST traceable Cargille standard R.I. liquids and guided procedure, including a printable verification report..
Process connectionPR-43-AC: Sanitary 3A-clamp 2.5”; Varivent in-line access unit clamp DN65 or via elbow flowcell (for line sizes of 2.5” and smaller); 2.5” Cherry-Burrell I-clamp.
PR-43-AP: Sanitary 3A-clamp 2.5”; Sanitary 3A-clamp 4” or MT4 DN 25/1T APV Tank bottom flange; 2.5” Cherry-Burrell I-clamp.
Hygienic design certification3-A Sanitary Standard 46-03 certified and EHEDG (European Hygienic Equipment Design Group) Type EL Class I certified.
Process pressureSanitary 3A and I-clamp max. 15 bar (200 psi) at 20°C (70°F)/9 bar (125 psi) at 120°C (250°F).
High pressure Sanitary 3A clamp HP 40 bar.
Process temperaturePR-43-AC: -40°C…130°C (-40°F…266°F), PR-43-AP: -40°C…150°C (-40°F…302°F).
Ambient temperatureRefractometer: min. -40°C (-40°F), max. 45°C (113°F); Multichannel user interface MI: min. -40°C (-40°F), max. 50°C (122°F);
Compact user interface CI: min. 0°C (32°F), max. 50°C (122°F).
Process wetted partsFor compact probe Stainless steel 1.4435 (AISI 316L), for long probe Stainless steel AISI 316L, prism sapphire, prism gasket modified PTFE (Teflon), sanitary process connection gasket EPDM for Sanitary 3A-clamp, I-line clamp and Varivent connection; EHEDG certified process connection gasket for EHEDG compliant installation.Hastelloy C ASTM C276
Sensor coverAISI 316L stainless steel.Compact user interface CI: min. 0°C (32°F), max. 50°C (122°F).
Refractometer protection classIP67, Type 4X.
Refractometer weightPR-43-AC: 1.6 kg (3.5 lbs), PR-43-AP: 2.9 kg (6 lbs).
Current outputIsolated 4-20 mA, max. load 1000 Ohm, galvanic isolation 1000 VDC or AC (peak), hold function during prism wash.
Fieldbus and industrial Ethernet connectivityThrough Fieldbus converter to Modbus/TCP, Modbus RTU and Ethernet/ IP networks.
Interconnecting CablesStandard length 10 m. Interconnecting cable length is field-adjustable with Platform 4 Cable extender for up to 100 m
User Interface ModelsMultichannel user interface MI, Compact user interface CI, Web user interface WI
Multichannel user interface MIEnvironmentally sealed 316 stainless steel IP67 (door closed), IP66 (door open), Type 4X enclosure. Prism wash diagnostics and control. Trends, Apps. Eight (8) module slots. 10” graphical touchscreen color display with door. 21 CFR 11 compliant user authentication with user ID and password, electronic records and data-logging, event log/audit trail. Expandable system and I/O options: connect up to four (4) PR-43-A refractometers and up to eight (8) I/O modules. Wall and table-top mount.
Compact user interface CILight-weight aluminum enclosure for control room conditions; Epoxy coated enclosure with polycarbonate display shield for field conditions, IP66/Type 4X. Trends. 10” graphical touchscreen color display. Wall, table-top and panel mount.
Web user interface WIOutput values are transmitted through 4-20 mA output and output values, diagnostic information and trends are transmitted via Ethernet connection using a UDP/IP protocol.
User interface weightMultichannel user interface MI: 13.6 kg (29 lbs), Compact user interface CI: 5.4 kg (11 lbs)
Power SupplyRefractometer: +24 VDC +/-10%, Max 2 VA; Multichannel user interface MI: AC input 100-240 VAC/50-60HZ or 24 VDC, 60W;
Compact user interface CI: +24 VDC +/-10%, Max. 8.5W.
OptionsPrism wash, Hazardous and intrinsic safety approvals for hazardous area installations.

Source: Vaisala K-Patents