Thermo Orion Star A111 Benchtop pH Meter

The Thermo Orion Star A111 benchtop pH meter with electrode stand records pH in the lab with Orion BNC pH electrodes.


  • User-friendly, three-button operation
  • Large LCD screen displays pH, mV and temperature readings
  • Specifically designed for environmental, industrial, and educational applications
List Price $636.00
Starting At $591.48
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Thermo Orion Star A111 Benchtop pH Meter

Thermo Orion Star A111 benchtop pH meters are simple to operate and provide accurate data. A large LCD displays pH, mV and temperature readings, while icons provide quick updates on battery life, electrode status and calibration information. User-friendly button layout and on-screen messages simplify calibration and explain setup menu choices.

Easy Integration
The Thermo Orion Star A111 benchtop pH meter offers ease of use with a simple three-button operation and is value priced for general purpose pH measurements in the laboratory. Specifically designed for environmental, industrial, and educational applications, this Thermo Orion pH meter is a significant upgrade from Thermo Scientific's Orion 2-Star benchtop pH meter.


  • AUTO-READ function alerts the user and locks on-screen readings when stable
  • Up to 3-point pH calibration
  • Automatic recognition of USA/NIST and DIN buffers
  • Easy to recall calibration slope data for procedure checks
  • Non-volatile memory holds up to 50 data points
  • Electrode arm and newly-designed probe holder to place probes into samples
  • Universal power supply or battery power option
  • IP54-rated housing
  • 3-year meter warranty
  • pH
  • Range: -2.00 to 16.00
  • Resolution: 0.1, 0.01
  • Relative Accuracy: +/-0.01
  • Calibration Points: Up to 3
  • mV
  • Range - mV: +/-1600.0 mV
  • Range - RmV: +/-1999.9 mV
  • Resolution: 0.1 mV
  • Relative Accuracy: +/-0.2mV or 0.05%, whichever is greater
  • Relative mV Calibration: Yes
  • Temperature
  • Range: -5 to 105 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: pH Electrode - BNC, ATC Probe - 8-pin mini-DIN
  • 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: IP54, splashproof and dustproof
  • Warranty: 36 months (from date of purchase)
Questions & Answers
Can this meter be set it so it won't shut off automatically?

The Thermo Orion Star A111 is designed to turn off after 15 minutes if there have been no key presses. However, this function can be disabled so that the meter will remain on until it loses power or the main power button is pressed. You can disable the auto-off function by pressing "setup", scrolling down until "General Meter Setup" is selected, clicking "mode" and selecting "AUTO". The default setting is "ON". Select "OFF" and press "mode" to save this setting as the new default.

Can my meter display temperature and pH simultaneously?

Yes the LCD screen will display pH or mV readings along with temperature.

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Thermo Orion Star A111 Benchtop pH Meter
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