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testo 340 - Flue gas analyzer for use in industry

0632 3340
  • Can measure CO, COlow, NO, NOlow, NO2 or SO2
  • Extended measuring range for use in environments with high gas concentrations
  • Precalibrated gas sensors for quick and easy sensor change
  • Integrated pressure difference and air flow measurements for mass flow calculations
  • Emission control in industry: the testo 340 flue gas analyzer gives you professional technology, easy handling and practical execution in one instrument. The high-performance testo 340 flue gas analyzer is fitted with an O2 sensor and can be equipped with up to 3 additional sensors.
    Precise technology: That’s what you want to be able to rely on when you’re working out in the field. But precise technology is nothing if it is not versatile, easy to use and adaptable for use in the field. The testo 340 flue gas analyzer ticks all these boxes.

    The testo 340 combustion analyzer. For industrial emission measurements and more

    Which sensors do you need in the course of your daily work and which measurements do you normally need to carry out? The testo 340 comes standard-fitted with an O2 sensor and four more sensors (CO, COlow, NO, NOlow, NO2 or SO2) for you to choose from, allowing you to customize your analyzer to suit your individual demands. The analyzer’s compact design and the reliable technology tucked away inside ensure increased mobility, making it ideal for use in international service operations and for installing or carrying out checks on firing plants or energy production systems. To find out more about the different application possibilities and to see which industrial applications your testo 340 flue gas analyzer is suitable for just click on the “Applications” tab.

    High gas concentrations? No problem with the testo 340!

    The flue gas analyzer has an extended measuring range which allows you to carry out measurements even when gas concentrations are very high (i.e. during industrial flue gas analysis). The extended measuring range (thinning) is activated automatically when high gas concentrations suddenly occur. The demands on the sensor are no different to than when the flue gas analyzer is used in low gas concentrations.

    testo 340 flue gas analyzer, calibration protocol, shoulder strap, O2 sensor and integrated flow and pressure difference measurements.

    PLEASE NOTE: Your testo 340 must be fitted with a second gas sensor for it to work. Up to three additional sensors can be fitted.

    Differential Pressure - Piezoresistive

    Measuring range
    -200 to 200 hPa
    ±1.5 % of mv (Remaining Range)
    ±0.5 hPa (-49.9 to 49.9 hPa)
    0.1 hPa

    Absolute Pressure

    Measuring range
    +600 to +1150 hPa
    ±10 hPa
    1 hPa

    Flue gas O₂

    Measuring range
    0 to 25 Vol.%
    ±0.2 Vol.%
    0.01 Vol.%
    Reaction time t₉₀
    < 20 s

    Flue gas probes

    Pitot tubes

    Temperature probes



    Analysis of the gas atmosphere (thermal processes)

    Flue gas analysis is used for thermal manufacturing processes, from ongoing emission control, via setting and optimisation of combustion systems, through to process monitoring. Flue gas analysis instruments serve to optimise operations and save fuel. At the same time, flue gas measurement enables checking and monitoring of flue gas emission limit values laid down by the authorities, along with functional testing of permanently installed emission instruments. Flue gas analysis instruments are increasingly used for monitoring process and product quality.

    Advantages of the testo 340

    Ideal for measurements at high concentrations

    • When recording extremely high concentrations, the measuring range extension is automatically activated. This enables continuation of the measurement. The gas sensor is not subjected to any higher stress than it is at low gas concentrations. This ensures the sensor has the longest possible service life.

    testo 340

    Service measurement on industrial engines

    Flue gas analysis instruments are one of the items of equipment that are used on a daily basis by service engineers to achieve optimum tuning of engines. Flue gas measurement is used on industrial engines when they are commissioned, at regular maintenance intervals or for troubleshooting when they are running in an unstable way. The background to flue gas measurement is tuning the engine to the optimum operating parameters while complying with the limit value regulations in force. Maintenance work that is carried out regularly makes an important contribution to avoiding downtimes over the long term, to ensuring the quality of the system and thus a high level of efficiency and to having a significant influence on emission levels.

    Advantages of the testo 340
    Separate NO and NO2 measurement

    • The real NOx value is measured with the NO and NO2 sensor combination. In gas engines, the NO2 component of the NOx value can fluctuate greatly, so the separate measurement of each of the gases is necessary for correct NOx values.

    Measurements even at high CO concentrations

    • At unexpectedly high concentrations (up to 50,000 ppm), the automatic dilution of the sensor with fresh air allows measurements even when the engine conditions are not defined, without negatively affecting the service life of the sensor.

    Special flue gas probes for industrial engines as an accessory

    • These probes are highly heat-resistant and specially designed to compensate for different pressure conditions, e. g. for measurements before and after the catalytic converter.

    Engine-specific parameters

    • The most important parameters for industrial engines such as O2, CO, NO, NO2, NOx and Lambda can be displayed simultaneously.

    testo 340

    Service measurement on industrial burners

    The testo 340 flue gas analysis instrument offers service engineers a vast range of technical functions. In addition to compliance with environmental regulations, it can also be used to check correct functioning and to optimise burner efficiency. Flue gas measurement is used on industrial burners for safe and efficient commissioning, at regular maintenance intervals or for troubleshooting when they are running in an unstable way.

    Advantages of the testo 340
    Time saving through helpful instrument pre-settings

    • Typical fuels, a sensible sequence of flue gas parameters in the display and useful instrument settings are preset for each application. Tips on the display take the user through the measurement (no prior knowledge specific to the instrument needed). The testo 340 is ready for operation within just a few minutes.

    Unrestricted measuring at high concentrations

    • When commissioning burners or carrying out measurements on unfamiliar systems, very high concentrations can occur unexpectedly. The measuring range extension is automatically activated in such cases.

    Always ready for use – even in tough day-to-day work

    • The robust housing protects the measuring instrument from knocks.

    testo 340