Thermo Orion Star A123 Portable Dissolved Oxygen Meter

The Thermo Orion Star A123 portable dissolved oxygen meter combines simplicity and accuracy for both lab and field DO readings.


  • Compatible with Orion polarographic DO sensors with 9-pin mini-DIN connectors
  • AUTO-READ function alerts user and locks on-screen readings when stable
  • IP67 waterproof rating, 3-year warranty
List Price $765.00
Starting At $726.75
Thermo Orion Star A123 Portable Dissolved Oxygen Meter

The waterproof, battery-operated Thermo Orion Star A123 portable DO meter stands up to the most demanding field applications and delivers over 2,000 hours of continuous operation. Multiple calibration options, automatic temperature compensation, and manual salinity and barometric pressure compensation make the A123 user-friendly and accurate.

The rugged, user-friendly meter displays DO concentration, DO saturation and temperature readings on a large LCD screen, while icons provide quick updates on battery life, electrode status and calibration information. Simple button layout and on-screen messages assist with calibration and explain setup menu choices.


  • AUTO-READ function alerts user and locks on-screen readings when stable
  • Calibration with either water-saturated air method or Winkler titration
  • Accepts Orion polarographic DO probes
  • Non-volatile memory holds up to 50 data points
  • Universal power supply or battery power option
  • IP67-rated housing
  • 3 year meter warranty
  • Dissolved Oxygen Concentration (% Sat)
  • Range: 0 to 20 mg/L (0 to 200 %)
  • Resolution: 0.1, 0.01 (0.1,1)
  • Relative Accuracy: +/-0.2 (+/-2 %)
  • Manual Barometric Pressure Compensation: 450.0 to 850.0 mm Hg
  • Manual Salinity Factor Correction: 0 to 45 ppt
  • Calibration Features: Water-saturated air, manual (Winkler)
  • Sensor type: Polarographic
  • Temperature
  • Range: 0 to 50 C
  • Resolution: 0.1
  • Relative Accuracy: +/-0.1 C
  • Compensation: Auto or Manual
  • Offset Calibration: Yes
  • Datalogging
  • Number of Points: 50
  • Log Function: Manual, Automatic with AUTO-READ
  • Log Edit: Delete last reading or all
  • General
  • Display: Custom LCD
  • Inputs: 9-pin mini-DIN
  • Weight: 450g
  • Power Adapter: Universal AC, 100-240 VAC
  • Battery Power: 4 AAs, 2000 hrs life
  • Environmental Requirements: 5 to 45 C and 5 to 85% relative humidity, non-condensing
  • Regulatory and Safety: CE, TUV 3-1, FCC Class A
  • IP Rating: IP67 (can be immersed for one hour with no water incursion)
  • Warranty: 36 months (from date of purchase)
Questions & Answers
What information does my screen display regularly?
The large screen shows the main information, including DO reading in mg/L or % saturation, temperature in °C or °F, meter mode and battery life.
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