missing translation for 'onlineSavingsMsg'
Learn More
Please login to your online account to display your discounted pricing

Thermo Scientific™ Orion Star™ A221 pH Portable Meter

Reliably measure pH, mV, ORP and temperature with the Thermo Scientific™ Orion™ Star A221 pH Portable Meter for advanced field analysis and printer or computer interfacing

Manufacturer:  Thermo Scientific™ ORISTARA2215

 View more versions of this product

Catalog No. 13-645-524



Record accurate and reliable pH, mV, ORP and temperature measurements with the Thermo Scientific™ Orion™ Star A221 pH Portable Meter, ideal for a wide range of applications and advanced pH analysis in the field. Perform up to a five point pH calibration, log up to 1000 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. Waterproof meter ensures durable, rugged performance in outdoor environments with an IP67-rated housing.

  • Multilanguage interface supports English, Spanish, French, Italian, German and Chinese
  • Thermo Scientific™ AUTO-READ™ locks in the stable reading on your screen and a "ready" indicator alerts when readings are stable
  • Meter includes up to five point pH calibration with automatic recognition for USA/NIST™ and DIN buffers.
  • Nonvolatile memory holds up to 1,000 datapoints with time and date stamp.
  • User can easily transfer data and keep meter software up-to-date with the USB and RS232 ports and complimentary data analysis software.
  • Four AA batteries (included) provide over 800 hours of operation or purchase the universal power adapter (sold separately) to use AC power.
  • Meter is perfectly portable, waterproof and protected to take anywhere with a IP67-rated housing.


Orion Star A221 pH portable meter kit with ROSS Ultra Triode low maintenance gel pH/ATC electrode, solutions, meter armor and field case
Orion Star A221 pH portable meter kit with ROSS Ultra Triode low maintenance gel pH/ATC electrode, solutions, meter armor and field case
-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
Smart Stability and Smart Averaging
1000 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 A221 pH/mV/RmV/ORP/Temperature Portable Meter
Star A221 pH Meter with Batteries; 8107UWMMD ROSS Gel-filled Epoxy pH/ATC Triode with 3 Meter Cable; 910410 pH 4.01 Buffer Pouches; 910710 pH 7.00 Buffer Pouches; 911010 pH 10.01 Buffer Pouches; 810001 ROSS Electrode Storage Solution; 911110 Rinse Solutio
0.1, 0.01, 0.001
±0.2 mV or ±0.05% of reading whichever is greater
pH, 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 measure mode; manual data logging with Continuous measure mode
Calibration due alarm (fixed 12 hour)
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 (includes 8107UWMMD ROSS Ultra Triode pH/ATC electrode)