Thermo Orion 261S Intrinsically Safe Basic pH Meter

Thermo Orion 261S Intrinsically Safe Basic pH Meter


Thermo Orion 261S intrinsically safe basic portable pH meter


  • Intrinsically safe and waterproof meter
  • 3-point autocalibration with choice of buffers or manual calibration
  • 3 year meter warranty
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Thermo Orion Intrinsically Safe Meters are designed for use where non-sparking equipment is desired, these meters carry US intrinsically safe approval rating by Factory Mutual (FM).

The Thermo Orion 261S was designed for accurate measurement of pH, mV, and temperature in the field and is rated as intrinsically safe for measurement in hazardous and confined space environments and anywhere non-sparking equipment is desired. A large easy-to-read display monitors electrode response condition and calibration status as well as pH, mV and temperature readings.

The battery-operated meter is supplied with a built-in quiver and neck strap. The meter and electrode package contains a rugged, low-maintenance Thermo Orion Triode 3-in-1 combination pH electrode.
Notable Specifications:
  • pH
  • Range: -2.00 to 16.00
  • Resolution: 0.1, 0.01
  • Accuracy: +/-0.01
  • Auto-Buffer Recognition: Dependent on buffer set (7 pre-programmed sets)
  • Calibration Points: 3
  • ORP
  • Range: +/-1300.0 mV
  • Resolution: 0.1 mV
  • Accuracy: +/-0.1% of value +0.3 mV
  • Temperature
  • Range: -20 to 120 C
  • Resolution: 0.1 C
  • Relative Accuracy: +/-0.3 C
  • General
  • Display: Custom LCD
  • Inputs: Waterproof DIN, 4mm Banana
  • Power Requirements: 3 x alkaline AA batteries
  • Agency Approvals: CE, FM, Ex(Intrinsically Safe)
  • Environmental Requirements: -10 C to 55 C
What's Included:
  • (1) Thermo Orion 261S Intrinsically safe basic pH meter
  • (1) Operations manual
Image Part # Product Description Price Stock Order
Thermo Orion 261S Intrinsically Safe Basic pH Meter 0261S2 Orion 261S intrinsically safe basic portable pH meter
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Thermo Orion Intrinsically Safe Basic pH Meter 0261S0 Orion 261S intrinsically safe basic portable pH meter with 9109WP low maintenance pH/ATC triode
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Thermo Orion 261S Intrinsically Safe pH Meter 0261S3 Orion 261S intrinsically safe basic portable pH meter with 9109WP pH/ATC triode, neck strap, field case, electrode holder, stand, pH buffers, and beakers
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Image Part # Product Description Price Stock Order
Thermo Orion pH/ATC Triode Electrodes 9109WP Orion pH/ATC Triode with epoxy body, low maintenance gel, waterproof EDIN & banana plug connector, 1m cable
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Thermo Orion All-in-One 475mL pH Buffer Kit 910199 Orion All-in-One pH buffer kit, (1) 475mL bottle ea. of pH 4, 7, 10; storage solution; storage bottle
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Questions & Answers

| Ask a Question
How long is the cable on the probe?
The 9109WP gel filled pH/ATC triode has a 1.5m cable. This electrode will come with the the kit options: 0261S0 or 0261S3.
How accurate is the Thermo Orion 261S?
The accuracy of the Thermo Orion 261S varies depending on the parameter measured. The meter measures pH with an accuracy of +/- 0.01, oxygen reduction potential at +/- 0.1% of value +0.3 mV, and temperature at +/- 0.3 degrees Celsius.

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