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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

$996.00 - $1,946.42


AC Adapter Universal 50-60 Hz, 100-240 VAC power adapter (sold separately, Cat. No. 1010003)
Accuracy (mV) ±0.2 mV or ±0.05% of reading whichever is greater
Accuracy (pH) ±0.002pH
Accuracy (Temperature) ±0.1°C
Alarm Output Calibration due alarm (fixed 12 hour)
View More Specs
Catalog Number Mfr. No. Description Includes Price Quantity    


thermo scientific™
Orion Star A221 pH portable meter Star A221 pH meter, 4 AA batteries, literature CD, printed quick start guide, computer interface cable and meter test certificate Each for $996.00


thermo scientific™
Orion Star A221 pH portable meter kit with ROSS Ultra Triode low maintenance gel pH/ATC electrode, solutions, meter armor and field case 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 Solution; STARA-AR Protective Armor with Electrode Holder; STARA-CS Hard Carrying Case Each for $1,946.42
Description & Specifications


AC Adapter Universal 50-60 Hz, 100-240 VAC power adapter (sold separately, Cat. No. 1010003)
Accuracy (mV) ±0.2 mV or ±0.05% of reading whichever is greater
Accuracy (pH) ±0.002pH
Accuracy (Temperature) ±0.1°C
Alarm Output Calibration due alarm (fixed 12 hour)
Backlight Option Yes, selectable
Battery Life 800 hours
Battery Type Four AA (included)
Calibration pH, relative mV (RmV), ORP and temperature
Calibration Points 1 point relative mV (RmV) mode, 1 point ORP mode
Calibration Points (pH) 1 to 5
Certifications/Compliance CE, TUV 3-1, FCC Class A
Channels 1
Data Management Details Transfer single, range or all data points to printer or computer
Data Points 1000 with date and time stamp
Display Type Graphic LCD with backlight
Dimensions (L x W x H) 24cm x 10cm x 6.5cm (9.5 in. x 3.9 in. x 2.6 in.)
IP Rating IP-67
Languages English, Spanish, French, Italian, German and Chinese; Portuguese and Korean available with software update
Log Function Type Automatic data logging with Auto-Read measure mode; manual data logging with Continuous measure mode
Outputs USB, RS232
Range (mV) ±2000.0mV
Range (pH) -2.000 to 20.000pH
Resolution (pH) 0.1, 0.01, 0.001pH
Inputs BNC (pH or ORP electrode), pin-tip (reference electrode), 8 pin MiniDIN (ATC temperature probe)
Isopotential Point 7.000pH
Keypad Comprehensive with menu-specific function keys and dual purpose scroll/shortcut keys
Measurement Modes pH, mV, relative mV (RmV) or ORP with temperature
Memory Non-volatile memory preserves data log, calibration log and meter settings
Methods 10 per channel with password protection
Model Orion Star A221 pH/mV/RmV/ORP/Temperature Portable Meter
Power Supply 4 AA batteries (included) or universal AC adapter (sold separately)
Range (ORP) ±2000.0mV
Range (Relative mV) ±2000.0mV
Range (Temperature) -5.0° to 105.0° C, 22.0° to 221.0° F
Relative Humidity Range 5 to 85 %, non-condensing
Resolution (mV) 0.1mV
Resolution (Temperature) 0.1°C, 0.1°F
Stability Smart Stability and Smart Averaging
Temperature (English) Operating 41° to 113°F (ambient)
Temperature (Metric) Operating 5° to 45° C (ambient)
Temperature Probe Calibration 1 point temperature offset calibration
Temperature Selection Manual or automatic with ATC temperature probe
Warranty 3 year meter warranty
Weight (English) 1.2 lb.
Weight (Metric) 0.5kg

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.

Don’t leave your measurements to chance when analyzing samples outside the lab. Orion Star A221 pH portable meters are designed to offer the reliability you need in a user-friendly package for your dedicated pH testing needs. This waterproof portable meter displays critical data with your measurement including temperature, date and time, read type, measurement stability, active calibration info and power source status.
  • Measure pH, mV, relative mV or ORP with temperature
  • Perform up to a five point pH calibration using automatic buffer recognition of NIST or DIN buffer groups with choice to manually enter custom buffer values
  • Informative, easy-to-read backlit graphic display with clear onscreen instructions simplifies operation
  • Capture your critical readings with measurement stability indicator and selectable read modes – Auto-Read holds a stable reading and Continuous shows changing readings with hold option 
  • Data log collects and date/time stamps up to 1000 measurement sets
  • Non-volatile meter memory ensures your data and settings are protected, even with loss of power
  • Orion Star Com software facilitates data transfer to a computer via USB or RS232 connections
  • 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 and 3-year replacement warranty

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