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  • Memory holds up to 5000 data points
  • AUTO-READ™ Technology
  • Four AA batteries (included) over 800hrs of operation
  • Linear or ISO/EN 27888 curves for TDS
  • Practical salinity or natural sea water curves for salinity
  • IP67-rated housing
  • 3 year meter replacement warranty
  • Waterproof

The Thermo Scientific Orion STAR A329 pH/ISE/Conductivity/RDO/Dissolved Oxygen Portable Meter is the top choice for advanced multiparameter measurements on location. Get the information you need quickly and easily from the large, backlit graphic LCD display. The informative display can show each parameter with temperature individually or all three with temperature on one screen. Additional helpful icons include electrode status, time, date, sample ID, user ID and calibration points. Advanced features such as stability and averaging options provide additional options allowing for laboratory accuracy everywhere you need it.

Anyone can use this meter with its plain language screen prompts, soft keys that update for easy selection and a multilanguage interface that supports English, Spanish, French, Italian, German and Chinese. The AUTO-READ™ feature locks in the stable reading on your screen, the ready indicator alerts when readings are stable and the timed reading gathers data in specific time intervals.

Additional features include:

  • Up to 5 point pH calibration with automatic recognition for USA/NIST and DIN buffers
  • Fix pH and ISE calibration errors without a complete recalibration with calibration editing
  • The meter accepts and automatically recognizes Orion polarographic and RDO optical/luminescence-based probes
  • It's easy to get accurate DO results with automatic temperature, automatic/manual barometric pressure and automatic salinity compensation when used with simultaneously with conductivity
  • Calibrate for DO using water-saturated air, air-saturated water, a Winkler titration or zero point calibration
  • Selectable cell constant allows for use with 2- or 4-cell conductivity cells
  • For advanced accuracy in conductivity readings, selectable reading reference temperatures of 5, 10, 15, 20 or 25 °C with linear, non-linear, nLFu or EP curve options
  • Whether you use ISE infrequently or have multiple samples every day – up to 5 point ISE calibration with advanced features such as timed end point, linear point-to-point, non-linear selectable auto-blank and low-concentration range stability
  • Easily transfer data and keep meter software up-to-date with the USB and RS232 ports and complimentary data analysis software

The STAR A3295 pH/ISE/Conductivity/Dissolved Oxygen Portable Multiparameter Meter Kit includes:

  • 8107UWMMD Orion ROSS Triode 3-in-1 pH/ATC probe, 3m cable
  • 013010MD Orion DuraProbe conductivity cell, 3m cable
  • 087010MD Orion RDO optical/luminescencebased probe with 3m cable, stainless steel guard, calibration sleeve and optical/luminescence-based cap
  • 910410 Orion pH 4.01 buffer, 10 pouches
  • 910710 Orion pH 7.00 buffer, 10 pouches
  • 911010 Orion pH 10.01 buffer, 10 pouches
  • 810001 Orion ROSS electrode storage solution, 475 mL
  • 01100710 Orion 1413 μS conductivity standard, 10 pouches
  • 911110 rinse solution, 10 pouches
  • Protective armor with probe holders
  • Hard carrying case
  • Four AA batteries (installed)


Thermo Scientific Orion Conductivity Cell
2-Electrode conductivity cells , SS K=0.1 Mini DIN, 1.5m, for labortatory and ultra pure water applications
Thermo Scientific Orion DuraProbe Conductivity 4-Cell
Conductivity 4-Cell, Mini DIN, 1.5M epoxy probe with a cell constant of 0.475
Thermo Scientific Orion Dissolved Oxygen Probes
Dissolved oxygen probes for your Thermo Scientific Orion meter
Thermo Scientific Orion pH Electrodes
pH electrodes available in a variety of styles
In Stock
Thermo Scientific Orion ROSS pH Electrodes
The best performing pH electrodes on the market available in various sizes, tips and special features
Thermo Scientific Orion ISE Electrodes
Measure ion concentrations in water, food, pharmaceuticals and biological samples


Thermo Scientific Orion Dissolved Oxygen Calibration Accessories
Calibration accessories for Thermo Scientific Orion dissolved oxygen electrodes


Thermo Scientific Orion Conductivity Standards
Conductivity standards for Thermo Scientific Orion conductivity electrodes
Thermo Scientific Orion Dissolved Oxygen Solution
Polarographic electrolyte solution for Thermo Scientific Orion dissolve oxygen electrodes
Thermo Scientific Orion pH Buffers
pH buffers for Thermo Scientific Orion pH electrodes
Thermo Scientific Orion All-in-One 60mL pH Buffer Kit
kit including 4.01, 7.00 and 10.00 buffers pH electrode storage solution and pH electrode cleaning solution
Thermo Scientific Orion pH Electrode Cleaning Solutions
Cleaning solutions for Thermo Scientific Orion pH electrodes
Thermo Scientific Orion pH Electrode Storage Solutions
Storage solutions for Thermo Scientific Orion pH electrodes
Thermo Scientific Orion ISE Calibration Standards
ISE calibration solutions for Thermo Scientific Orion ISE electrodes
Thermo Scientific Orion ISE Filling Solutions
ISE calibration solutions for Thermo Scientific Orion ISE electrodes
Thermo Scientific Orion ISE Ionic Strength Adjusters (ISA) & Special Reagents
ISE ionic strength adjusters (ISA) and special reagents for Thermo Scientific Orion ISE electrodes


Please consider these optional accessories.

Thermo Scientific Orion STARA-CS Carrying Case
Hard carrying case for the Orion A-series
Thermo Scientific Orion Armor
Orion Star A series portable meter protective armor with hand strap/built-in stand, storage sleeve, and holders
Thermo Scientific Orion STARA-ESCD Probe Holder
Conductivity and DO probe holder for use with armor, Orion Star A
Thermo Scientific Orion STARA-ESPH pH Electrode Holder
Holds one pH electrode in the pH electrode sleeve, can be attached to either side of the meter armor
Thermo Scientific Orion STARA-BEA Electrode Arm
Electrode Arm, Orion Star A, no base
Thermo Scientific Orion STARA-HB Base
Base, Orion Star A, for use with benchtop electrode arm
Thermo Scientific Orion Conductivity Accessories
Conductivity accessories for Thermo Scientific Orion conductivity electrodes