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Thermo Scientific™ Orion Star™ A321 pH Portable Meter

Accurately monitor pH, mV, ORP and temperature with the Thermo Scientific™ Orion™ Star A321 pH Portable Meter for waterproof, high performance in challenging field locations

Manufacturer:  Thermo Scientific™ ORISTARA3210

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Catalog No. 13-645-551



Get high accuracy and premium performance everywhere you need it with the Thermo Scientific™ Orion™ Star A321 pH Portable Meter, designed for a wide range of pH, mV, ORP and temperature testing and field applications. Evaluate samples in the most demanding locations using this waterproof meter with IP67-rated housing. Perform up to a five point pH calibration, log up to 5000 data point sets with time / date stamp and easily transfer calibration and data logs via USB or RS232 to a printer or computer with free downloadable Orion™ Star Com software.

The Thermo Scientific Orion Star A321 pH Portable Meter is the top choice for advanced measurements on location. Get the information you need quickly and easily from the large, backlit graphic LCD display. Informative display shows pH/mV/RmV and temperature along with 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
  • Don't miss a reading — AUTO-READ™ locks in the stable reading on your screen, ready indicator alerts when readings are stable and timed reading gathers data in specific time intervals
  • Up to five point pH calibration with automatic recognition for USA/NIST™ and DIN buffers
  • Fix errors without a complete recalibration with calibration editing
  • Nonvolatile memory holds up to 5000 datapoints with time and date stamp
  • Easily transfer data and keep meter software up to date with the USB and RS232 ports and complimentary data analysis software
  • Purchase the universal power adapter (sold separately) to use AC power or use the four included AA batteries for over 800 hours of operation
  • Perfectly portable, waterproof and protected to take anywhere with a IP67-rated housing
  • Three year meter replacement warranty


Orion Star A321 pH portable meter
Orion Star A321 pH portable meter
-2.000 to +20.000
1 to 5
1 point temperature offset calibration
LCD (Graphic with backlight)
Comprehensive with menu-specific function keys and dual purpose scroll/shortcut keys
Selectable fast, medium, slow or Smart Stability setting; Selectable off or Automatic Smart averaging setting
5000 with date and time stamp
Non-volatile memory preserves data log, calibration log and meter settings
English, Spanish, French, Italian, German and Chinese; Portuguese and Korean available with software update
USB, RS-232
Universal 50-60 Hz, 100-240 VAC power adapter (sold separately, Cat. No. 1010003)
4 x AA
CE, TUV 3-1, FCC Class A
5° to 45°C (ambient)
24cm x 10cm x 6.5cm (9.5 in. x 3.9 in. x 2.6 in.)
22.0° to 221.0° F
3 year meter warranty
Orion Star A321 pH/mV/RmV/ORP/Temperature Portable Meter
Star A321 pH meter, 4 AA batteries, literature CD, printed quick start guide, computer interface cable and meter test certificate
0.1, 0.01, 0.001
±0.2 mV or ±0.05% of reading whichever is greater
pH with calibration editing option, relative mV (RmV), ORP and temperature
0.1°C, 0.1°F
Manual or automatic with ATC temperature probe
Yes, selectable
pH, mV, relative mV (RmV) or ORP with temperature
Transfer single, range or all data points to printer or computer
Automatic data logging with Auto-Read and Timed measure modes; manual data logging with Continuous measure mode
High/low limit alarm, calibration due alarm
BNC (pH or ORP electrode), pin-tip (reference electrode), 8 pin MiniDIN (ATC temperature probe)
Universal AC adapter (included) or 4 AA batteries (sold separately)
800 hr.
41° to 113°F (ambient)
5 to 85%, non-condensing
1.2 lb.
10 per channel with password protection
-5.0° to 105.0° C
pH electrode, ORP electrode, reference half-cell electrode, ATC temperature probe (purchase separately)