To properly tune and maintain turbines, an analyzer must measure accurate O2, low NOx, and low CO concentrations. The 350 has both the low range (0.1 ppm) and upper range capability needed for turbine testing. Combining field-proven technologies and a simple user interface, the 350 makes testing more accurate and easier than ever before.

Wireless operation (over 300 feet) allows you to make combustion adjustments at a convenient location, instead of at the sample port. No need to remove the probe from the stack - simply press the "fresh air purge" button on your control unit or Android device - increase sensor life and stay off ladders.

Large on-board memory and fresh air purging with the automatic test program allows data collection for weeks at a time. The high-definition color display shows real-time measurement data from one - or multiple - 350 measuring units. And with Testo easyEmission software, you can collect, sort, and analyze your data in real time.


Turbine-specific menus take the guess work out of testing - the 350 automatically selects the correct testing parameters for your application. And with available 0.1 ppm NOx resolution, you can easily see and calculate even the smallest combustion changes.

For EPA and high-accuracy testing, the available Active Sample Gas Conditioning System uses a built-in thermoelectric cooler with automatic condensate removal pump to deliver dry-basis data required for most reporting. In addition, the new, more powerful sample pump automatically controls sample flow rate for EPA accuracy testing.

Measuring Capabilities

O2 NO Hydrocarbons
CO NOlow Velocity
COlow NO2 Pressure
NOx SO2 Temperature
CO2 H2S Dilution


Turbine Probes from Testo are designed specifically to handle the unique challenges associated with turbine testing, with features that include:

  • Modular design for tool-free probe changes

  • Integrated thermocouple

  • Hi-temp probes for applications up to 1832°F

  • Teflon-lined hoses to ensure sample integrity

  • Optional sintered filter for heavy coal/fuel particulate loads

  • Optional pitot tube to measure velocity and flow

  • 9 ft. hose extensions available (5 extensions maximum)



Innovative technology has long been a signature of German manufacturers, and even among all the advanced features of the 350, this one is particularly revolutionary: control your analyzer with your Android smartphone/tablet using the free Testo app from Google Play.

This game-changing feature, exclusively from Testo, allows you to control all functions of your analyzer, including starting/stopping readings, purging gas, and changing testing parameters, all from your phone, and from up to 300 feet away.

You can also view real-time measuring data in either numerical or graphical form, and save the data to your phone. Even email readings direct from the app - no more looking for measurement printouts. The future is here - work smarter with Testo.



Simultaneous catalyst measurements used to mean using an expensive and complex trailer-mounted testing rig. Not anymore. With the 350, multiple analyzers can be linked together to read catalyst measurements.

Simply connect two or more (up to 16) probes and analyzer boxes to the exhaust stack (each analyzer can be configured to test either pre- or post-catalyst exhaust gas). Then just connect the analyzer boxes using a data cable, and you can read real-time measurements from each box on a single hand-held control unit. Even display two measurements side-by-side. And when you finish testing, use Testo easyEmission software to analyze and export your readings.