Thermo Scientific Orion Star A121 Portable pH Meters

Take simple, routine pH, mV and temperature measurements with the Thermo Scientific™ Orion Star™ A121 Portable pH Meter. This meter is an easy-to-use and budget-friendly instrument for basic pH analysis in the field. Perform up to a 3 point pH calibration with easy recall of calibration points and slope. Quickly navigate setup menus and ensure consistent calibrations using the simple keypad layout and on-screen text prompts. This waterproof meter has an IP67-rated housing for rugged protection in outdoor environments

Specifications for Thermo Scientific Orion Star A121 Portable pH Meters
pH mV Temperature
Range -2.00 to   16.00 ±1500.0 mV -5º to 105°C;
23 to 221ºF
Resolution 0.1, 0.01 0.1 0.1
Relative Accuracy ±0.01 ±0.2 mV or ±0.05 % of reading
whichever is greater
Calibration Points Up to 3 - -


Thermo Scientific Orion Star A121 Portable pH Meters are a simple, economical solution for your routine outdoor sample analysis. Featuring an emphasized measure key, selectable read modes and measurement stability indicator, our basic Orion Star A121 pH Meters are designed to deliver measurements you can trust at an affordable price.
  • Measure pH, mV or relative mV with temperature
  • Perform up to a 3 point pH calibration with automatic buffer recognition or manual buffer entry
  • Simplified, easy-to-read display shows main measurement with temperature, stability indicator and electrode condition icon
  • User-friendly operation with basic calibration text prompts
  • Easily recall calibration data for procedure checks
  • Non-volatile memory preserves 50 point internal data log and meter settings, even with loss of power
  • Flexible power options with AA batteries or optional universal power adapter
  • IP67-rated housing is waterproof for rugged field operation
  • Meter kits include hard-sided field case and protective meter armor with electrode holders, adjustable wrist/belt strap and built-in meter stand
  • Meters offer CE, TUV 3-in-1 and FCC Class A certifications
  • 3-year replacement warranty
Item Meter Model Type Unit of Measure Price Purchase
A121 pH Each
In Stock
A121 standard kit with general purpose pH/ATC electrode pH Each
In Stock

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